北山 丈二

A 48-year-old man underwent skin grafting from the left inguinal region to the left forearm one month previously. He noticed abdominal discomfort after discharge and was admitted to another hospital because of progression of abdominal pain and a decreased level of consciousness. An enhanced CT scan revealed extensive portal venous thrombosis. Lower gastrointestinal bleeding developed the following day, and he was transferred to our hospital and diagnosed with superior mesenteric venous thrombosis. Enhanced CT showed no intestinal necrosis. Anticoagulant therapy was started and the thrombosis had almost resolved 40 days later. However, after starting oral intake, the patient developed vomiting. Small bowel radiographs and 3D-CT showed significant proximal intestinal stenosis. Small bowel resection was performed on the 59th day after transfer. The pathological diagnosis was ischemic enteritis with venous thrombosis. The patient was discharged 20 days after intestinal resection and he has had no recurrence of symptoms. In this case, 3D-CT was useful to determine the range of intestinal stenosis and the required area of resection.

Aim: PD-1/PD-L1 blockade therapy is now widely used for the treatment of advanced malignancies. Although PD-L1 is known to be expressed by various host cells as well as tumor cells, the role of PD-L1 on non-malignant cells and its clinical significance is unknown. We evaluated cell type-specific expression of PD-L1 in colorectal cancer (CRC) specimens using multicolor flow cytometry. Methods: Single cell suspensions were made from 21 surgically resected CRC specimens, and immunostained with various mAbs conjugated with different fluorescent dyes. Tumor cells, stromal cells, and immune cells were identified as CD326(+), CD90(+) and CD45(+) phenotype, respectively. CD11b(+) myeloid cells, CD19(+) B cells and CD4(+) or CD8(+) T cells were also stained in different samples, and their frequencies in the total cell population and the ratio of PD-L1(+) cells to each phenotype were determined. Results: PD-L1 was expressed by all the cell types. The ratio of PD-L1(+) cells to CD326(+) tumor cells was 19.1% ± 14.0%, lower than those for CD90(+) stromal cells (39.6% ± 16.0%) and CD11b(+) myeloid cells (31.9% ± 14.3%). The ratio of PD-L1(+) cells in tumor cells correlated strongly with the ratio in stromal cells, while only weakly with that in myeloid cells. Tumor cells were divided into two populations by CD326 expression levels, and the PD-L1 positive ratios were inversely correlated with the rate of CD326 highly expressing cells as well as mean fluorescein intensity of CD326 in tumor cells, while positively correlated with the frequencies of stromal cells or myeloid cells in CRC. Conclusion: PD-L1 is differentially expressed on various cell types in CRC. PD-L1 on tumor cells may be upregulated together with CD326 downregulation in the process of epithelial mesenchymal transition. Quantification of cell type-specific expression of PD-L1 using multicolor flow cytometry may provide useful information for the immunotherapy of solid tumors.

BACKGROUND: The frequency of tumor cell dissemination in the peritoneal cavity is critically related to the progression of peritoneal metastases (PM). Recently, flow cytometry (FCM) has been successfully used to detect tumor cells in malignant effusions. METHODS: A total of 143 single cell suspensions derived from ascites or peritoneal lavages from patients with advanced gastric cancer (GC) were stained with monoclonal antibodies to CD45 and to CD326 as well as 4,6-diamidino-2-phenylindole (DAPI) and FVS780. Using FCM, tumor-leukocyte ratio (TLR) were calculated from CD45(-)CD326(+) tumor cell counts/ CD45(+)CD326(+) leukocyte counts in DAPI (+) FVS780(-) gated area. In 54 patients, the ratios of CD11b(+), CD4(+) and CD8(+) cells in CD45(+) leukocytes were evaluated in parallel. RESULTS: TLR of 69 patients with PM were significantly higher than those of 74 without PM (p < .001) and log(TLR) showed strong correlation with peritoneal cancer index scores in 51 PM (+) patients (r = 0.439). TLR in PM (+) patients also correlated with the ratio of CD11b (+) myeloid cells (r = 0.547), and correlated inversely with those of CD4(+) (r = -0.490) and CD8(+) T cells (r = -0.648). In PM (-) patients who underwent gastrectomy, TLR never exceeded 0.1% in patients with primary GC without serosal involvement (<T4). However, TLR in patients with T4 GC were significantly higher (p < .05) and peritoneal recurrence occurred in 6/8 patients whose TLR exceeded 0.1%. CONCLUSION: TLR in peritoneal fluid reflects tumor burden and the immune environment in peritoneal cavity. Multicolor FCM may provide additional information which can be used for the treatment of the patients with PM.

BACKGROUND: Intraperitoneal (IP) administration of paclitaxel (PTX) has a great pharmacokinetic advantage to control peritoneal lesions and can be combined with various systemic chemotherapies. In this study, we evaluate the efficacy and tolerability of a combination of IP-PTX and systemic S-1/oxaliplatin (SOX) for induction chemotherapy for patients with peritoneal metastases (PM) from gastric cancer (GC). PATIENTS AND METHODS: Patients with GC who were diagnosed as macroscopic PM (P1) or positive peritoneal cytology (CY1) by staging laparoscopy between 2016 and 2019 were enrolled. PTX was IP administered at 40 mg/m2 on days 1 and 8. Oxaliplatin was IV administered at 100 mg/m2 on day 1, and S-1 was administered at 80 mg/m2/day for 14 consecutive days, repeated every 21 days. Survival time and toxicities were retrospectively explored. RESULTS: Forty-four patients received SOX + IP-PTX with a median (range) of 16 (1-48) courses, although oxaliplatin was suspended due to the hematotoxicity or intolerable peripheral neuropathy in many patients. The 1-year overall survival (OS) rate was 79.5% (95% CI 64.4-88.8%) with median survival time of 25.8 months. Gastrectomy was performed in 20 (45%) patients who showed macroscopic shrinkage of PM with a 1-year OS rate of 100% (95% CI 69.5-100%). Grade 2 and 3 histological responses was achieved in four (20%) and one (5%) patients. Grade 3/4 toxicities included neutropenia (11%), leukopenia (39%), and anemia (14%). There were no treatment-related deaths. CONCLUSIONS: Combination chemotherapy using SOX + IP-PTX regimen is highly effective and recommended as induction chemotherapy for patients with PM from GC.

BACKGROUND: Repeat intraperitoneal (IP) chemotherapy has been successfully used for treatment of peritoneal metastases (PM) from gastric cancer (GC). Exosomes play important roles not only in tumor progression but also in chemoresistance via transfer of microRNAs (miRNAs). However, there is little evidence of an effect of miRNAs in peritoneal exosomes on chemosensitivity of peritoneal lesions. METHODS: In 74 patients with advanced GC who underwent staging laparoscopy, exosomes were isolated from peritoneal fluid and expression levels of miR-21-5p, miR-223-3p, and miR-29b-3p determined using TaqMan Advanced miRNA assays. In 43 patients with PM treated with combination chemotherapy, S-1 plus Oxaliplatin together with IP Paclitaxel, the relationship between their relative expression levels and outcomes was examined. RESULTS: The ratios of miR-21-5p/miR-29b-3p and miR-223-3p/miR-29b-3p were significantly upregulated in patients with PM, especially in patients with high serum CA125 levels. They showed a mild association with Peritoneal Cancer Index (PCI) score and ascites. More impressively, the ratios were significantly higher in 16 patients with progression of PM within 1 year compared with 27 patients with an excellent tumor response (miR-21-5p/miR-29b-3p: median 17.49, range 1.83-50.90 vs. median 4.64, range 0.40-38.96, p = 0.0015, miR-223-3p/miR-29b-3p: median 1.02, range 0.23-25.85 vs. median 0.21, range 0.01-50.07, p = 0.0006). Overall survival of patients with high miR-21/miR-29b or miR-223/miR-29b ratios was significantly worse than in patients with low ratios (p = 0.0117, p = 0.0021). CONCLUSIONS: The ratios of miRNAs in peritoneal exosome correlate with survival of the patients with PM from GC and suggest the possibility that they modify the chemosensitivity against IP chemotherapy.

Accumulating evidence suggests that metformin reduces the incidence and mortality of colorectal cancer (CRC). However, underlying mechanisms have not been fully clarified. The aim of this study was to examine the pathological characteristics of resected CRC from patients treated with metformin for type 2 diabetes mellitus (DM). In total, 267 patients with DM underwent curative colectomy for Stage I-III CRC and 53 (19.9%) patients had been treated medically including metformin. Pathological N-stage was significantly lower in metformin-treated patients (P < .05) with prolonged disease-free survival (DFS) (P < .05). Immunohistochemistry showed that the densities of CD3(+) and CD8(+) tumor-infiltrating lymphocytes (TILs) in the invasive front area were significantly higher in 40 patients treated with metformin compared with propensity score matched cases without metformin (P < .05). The density of tertiary lymphoid structures (TLS) in tumor stroma was markedly increased in metformin-treated patients (P < .001). In those tumors, there were more CD68(+) tumor-associated macrophages (TAM) infiltrated (P < .05), while the ratio of CD163(+) M2-phenotype was markedly reduced (P < .001). Stromal fibrosis tended to be suppressed by metformin intake (P = .051). These findings suggested that metformin drastically changes the characteristics of infiltrating immune cells in CRC and reprograms the tumor microenvironment from immunosuppressive to immunocompetent status, which may lead to suppression of microscopic tumor spread and improve the outcomes of patients with CRC and type 2 DM.

＜文献概要＞ポイント ◆タキサン腹腔内反復投与は長期にわたり高い腹腔内濃度が維持され,全身化学療法と併用することで胃癌腹膜播種に対して著効を示す.◆全身+腹腔内併用化学療法が奏効し「腹膜播種が消えた」症例に対し,conversion gastrectomyを施行すると長期生存が期待できる.◆全身+腹腔内併用化学療法中の腹腔内液サンプル中のCEAmRNAの定量は,conversion gastrectomyの適応を決めるうえで有用な情報となる.

Intestinal ischemia/reperfusion (I/R) injury is a life-threatening complication that leads to inflammation and remote organ damage. The NLRP3 inflammasome regulates the caspase-1-dependent release of IL-1β, an early mediator of inflammation after I/R injury. In this study, we investigated the role of the NLRP3 inflammasome in mice with intestinal I/R injury. Deficiency of NLRP3, ASC, caspase-1/11, or IL-1β prolonged survival after intestinal I/R injury, but neither NLRP3 nor caspase-1/11 deficiency affected intestinal inflammation. Intestinal I/R injury caused acute lung injury (ALI) characterized by inflammation, reactive oxygen species generation, and vascular permeability, which was markedly improved by NLRP3 deficiency. Bone marrow chimeric experiments showed that NLRP3 in non-bone marrow-derived cells was the main contributor to development of intestinal I/R-induced ALI. The NLRP3 inflammasome in lung vascular endothelial cells is thought to be important to lung vascular permeability. Using mass spectrometry, we identified intestinal I/R-derived lipid mediators that enhanced NLRP3 inflammasome activation in lung vascular endothelial cells. Finally, we confirmed that serum levels of these lipid mediators were elevated in patients with intestinal ischemia. To our knowledge, these findings provide new insights into the mechanism underlying intestinal I/R-induced ALI and suggest that endothelial NLRP3 inflammasome-driven IL-1β is a novel potential target for treating and preventing this disorder.

BACKGROUND: Anti-tumor effects of radiation therapy (RT) largely depend on host immune function. Adenosine with its strong immunosuppressive properties is an important immune checkpoint molecule. METHOD: We examined how intra-tumoral adenosine levels modify anti-tumor effects of RT in a murine model using an anti-CD73 antibody which blocks the rate-limiting enzyme to produce extracellular adenosine. We also evaluated CD73 expression in irradiated human rectal cancer tissue. RESULTS: LuM-1, a highly metastatic murine colon cancer, expresses CD73 with significantly enhanced expression after RT. Subcutaneous (sc) transfer of LuM-1 in Balb/c mice developed macroscopic sc tumors and microscopic pulmonary metastases within 2 weeks. Adenosine levels in the sc tumor were increased after RT. Selective RT (4Gyx3) suppressed the growth of the irradiated sc tumor, but did not affect the growth of lung metastases which were shielded from RT. Intraperitoneal administration of anti-CD73 antibody (200 μg × 6) alone did not produce antitumor effects. However, when combined with RT in the same protocol, anti-CD73 antibody further delayed the growth of sc tumors and suppressed the development of lung metastases presumably through abscopal effects. Splenocytes derived from RT+ CD73 antibody treated mice showed enhanced IFN-γ production and cytotoxicity against LuM-1 compared to controls. Immunohistochemical studies of irradiated human rectal cancer showed that high expression of CD73 in remnant tumor cells and/or stroma is significantly associated with worse outcome. CONCLUSION: These results suggest that adenosine plays an important role in the anti-tumor effects mediated by RT and that CD73/adenosine axis blockade may enhance the anti-tumor effect of RT, and improve the outcomes of patients with locally advanced rectal cancer.

The peritoneal surface is the most frequent site of metastasis disease in patients with gastric cancer. Even after curative surgery and adjuvant chemotherapy, peritoneal recurrences often develop. Exosomes play pivotal roles in tumor metastasis via the transfer of microRNAs (miRNAs). In the present study, exosomes were isolated from peritoneal lavage fluid or ascites in 85 patients with gastric cancer and the relative expression levels of miR‑29s were examined. The expression of miR‑29a‑3p, miR‑29b‑3p and miR‑29c‑3p in peritoneal exosomes were all downregulated in patients with peritoneal metastases (PM) compared to those without PM. In 30 patients who underwent curative gastrectomy with serosa‑involved (T4) gastric cancer, 6 patients exhibited recurrence in the peritoneum within 12 months. The expression levels of miR‑29s at gastrectomy tended to be lower in these 6 patients than in the other 24 patients with significant differences in miR‑29b‑3p (P=0.003). When the patients were divided into two groups based on median levels of miR‑29s, peritoneal recurrence developed more frequently in patients with low expression of miR‑29b‑3p, and lower expression of miR‑29s were related with worse overall survival. miR‑29s are thought to play a suppressive role in the growth of disseminated peritoneal tumor cells. Reduced expression of miR‑29b in peritoneal exosomes is a strong risk factor of developing postoperative peritoneal recurrence.

BACKGROUND: Despite recent progress in systemic chemotherapy, the prognosis of patients with peritoneal metastases from gastric cancer is still poor. Efficacious intraperitoneal and systemic combination chemotherapy regimens to treat patients with peritoneal metastases have recently been developed. CASE PRESENTATION: A 74-year-old man with gastric cancer T4b (transverse mesocolon) N3 M1 (peritoneum) received combination chemotherapy with intraperitoneal administration of paclitaxel, intravenous oxaliplatin, and oral S-1. Eight courses of combined chemotherapy had remarkable anti-tumor effects on the primary lesion, lymph node metastases, and peritoneal metastases. Total gastrectomy with regional lymph node dissection was performed. Pathological examination revealed no viable tumor cells in the resected specimens. After gastrectomy, the patient received 25 courses of the same chemotherapy without oxaliplatin and has no evidence of recurrence 24 months later. DISCUSSION: Therapeutic approaches including systemic chemotherapy, extended resection, and heated intraperitoneal chemotherapy have been used to treat patients with peritoneal metastases. Repeat therapy with intraperitoneal paclitaxel has been used recently. Intraperitoneal administration of paclitaxel results in prolonged retention in the peritoneal cavity with effects against peritoneal metastases. Repeated administration of paclitaxel does not cause adhesions in the peritoneal cavity. When combination chemotherapy is effective, salvage gastrectomy is a promising option with minimal morbidity and mortality. CONCLUSION: Combined chemotherapy with intraperitoneal paclitaxel and systemic chemotherapy followed by gastrectomy is a promising strategy for patients with advanced gastric cancer and peritoneal metastases.

BACKGROUND: Low-density neutrophils (LDN) have been shown to be increased in peripheral blood in patients with various diseases and closely related to immune-mediated pathology. However, the frequency and function of LDN in circulating blood of the patients following abdominal surgery have not been well understood. METHODS: LDN were determined by CD66b(+) cells, which were copurified with mononuclear cells by density gradient preparations of peripheral blood of surgical patients. The effects of the purified LDN on T cell proliferation and tumor cell lysis were examined in vitro. Neutrophil extracellular traps (NETs) production was examined by extracellular nuclear staining. RESULTS: The number of LDN with an immature phenotype is markedly increased in peripheral blood samples in patients after abdominal surgery. The frequency of LDN correlated positively with operative time and intraoperative blood loss. The purified LDN significantly suppressed the proliferation of autologous T cells stimulated with anti-CD3 mAb coated on plate and partially inhibited the cytotoxicity of lymphocytes activated with recombinant interleukin-2 against a human gastric cancer cell, OCUM-1. The LDN also produced NETs after short-term culture in vitro, which efficiently trap many OCUM-1. These results suggest that surgical stress recruits immunosuppressive LDN in the circulation in the early postoperative period. CONCLUSIONS: The LDN may support the lodging of circulating tumor cells via NETs formation and inhibit T cell-mediated antitumor response in target organs, which may promote postoperative cancer metastases. Functional blockade of LDN might be an effective strategy to reduce tumor recurrence after abdominal surgery.

INTRODUCTION: Intraperitoneal (IP) chemotherapy is a promising treatment option for gastric cancer (GC) with peritoneal metastasis (PM). Recently, superiority of IP administration of paclitaxel (PTX) combined with S-1 and intravenous PTX over conventional systemic chemotherapy was suggested in a phase III study, although the difference in overall survival did not reach statistical significance in the primary analysis. Thus, attempts to combine IP PTX with other systemic therapies with higher efficacy are warranted. We designed a new regimen combining IP PTX with S-1 plus cisplatin (SP), which is regarded as the standard first-line treatment for metastatic GC in Japan, and subsequently carried out a dose-escalation study. METHODS: The combination was a 5-weekly regimen. IP PTX was to be administered on days 1, 8, and 22 with an initial dose of 15 mg/m2 at level 1 and 20 mg/m2 at level 2. S-1 was to be administered orally at a fixed dose of 80 mg/m2 b.i.d. for 21 days followed by a -14-day rest. Cisplatin was to be administered intravenously at a dose of 60 mg/m2 on day 8. Dose-limiting toxicities (DLTs) were defined as grade 4 leukopenia, grade 3 (G3) febrile neutropenia, G3 thrombocytopenia, and G3 nonhematological toxicity. RESULTS: A total of 9 patients with macroscopic PM were enrolled. No DLTs were observed among the 3 patients at level 1 and 6 patients at level 2. No adverse events or technical problems associated with the IP administration were observed. Consequently, the maximum-tolerated dose was not reached, and the dose for further clinical trials of IP PTX was determined as 20 mg/m2. As for efficacy, peritoneal lavage cytology turned negative after the first course in 4 of 7 patients who had positive cytology before treatment. CONCLUSION: The present study determined the dose for further clinical trials of IP PTX to be 20 mg/m2, when combined with the 5-weekly SP regimen.

Aim: Peritoneal metastases (PM) frequently occur in patients with gastric cancer and result in a poor prognosis. Exosomes play pivotal roles in tumor metastasis through the transfer of microRNAs (miRNAs). We examined the exosomal miRNA profile in peritoneal fluids to identify novel biomarkers to reflect tumor burden in the peritoneum. Methods: Exosomes were isolated from peritoneal fluids of patients of gastric cancer with macroscopic (P1) or microscopic (P0CY1) peritoneal metastasis (PM) and comprehensive miRNA expression analysis was carried out. Expressions of candidate miRNAs were then validated in all 58 samples using TaqMan Advanced miRNA Assays. Results: In initial screening, we carried out comprehensive analysis of exosomal miRNA using peritoneal fluids from 11 and 14 patients with or without PM, respectively, and identified 11 dysregulated miRNAs in PM (+) samples. Validation analysis showed that four miRNAs (miR-21-5p, miR-92a-3p, miR-223-3p, and miR-342-3p) were significantly upregulated in 12 PM (+) samples, and their expression levels showed positive correlation with peritoneal cancer index. In contrast, miR-29 family were all downregulated in patients with PM (+) samples. Moreover, in 24 patients with pT4 tumor, miR-29 at gastrectomy tended to be lower in six patients with peritoneal recurrence with significant differences in miR-29b-3p (P = .012). Conclusion: Expression pattern of miRNAs in peritoneal exosomes well reflects the tumor burden in the peritoneal cavity and could be a useful biomarker in the treatment of PM.

INTRODUCTION: Gastric adenocarcinomas with low grade atypia may be difficult to diagnose as gastric cancer by preoperative biopsy. We report an extremely well-differentiated adenocarcinoma (EWDA) of the stomach which appeared like a submucosal tumor diagnosed by preoperative endoscopic submucosal dissection. PRESENTATION OF CASE: A 70-year-old male was referred with a 3-month history of a submucosal-appearing lesion in the gastric wall found on endoscopy. Biopsies of the lesion were performed and were inconclusive for neoplasia. Endoscopic ultrasonography showed a low echoic tumor growing into the fourth layer of the gastric wall. It was difficult to identify the tumor by repeat biopsy. Endoscopic submucosal dissection of the lesion was performed and revealed adenocarcinoma, and laparoscopic total gastrectomy was performed. Histopathologic evaluation showed that the tumor was stage IIA (T3N0M0). There is no recurrence 12 months after resection. DISCUSSION: Gastric EWDAs are rare lesions, accounting for 0.6% of all gastric cancers. It is difficult to diagnose gastric EWDA especially if it appears like a submucosal tumor. This lesion was finally diagnosed by endoscopic submucosal dissection. CONCLUSION: Endoscopic submucosal dissection may facilitate establishing the preoperative diagnosis of a tumor thought to be a gastric EWDA based on its endoscopic appearance and pathological findings.

A 68-year-old male was referred with dysphagia. Endoscopic findings showed circular stenosis with a protruding mass in the lower esophagus. Biopsy showed adenocarcinoma and there was no evidence of distant metastases. A subtotal esophagectomy was performed. The resected specimen revealed a mixed neuroendocrine carcinoma with adenocarcinoma. The adenocarcinoma component was on the surface of the tumor and the neuroendocrine component invaded the deeper portion. Immunohistochemically, the neuroendocrine carcinoma component stained positive for cytokeratin 7 and cytokeratin 20, suggesting that the neuroendocrine carcinoma originated from the adenocarcinoma. The adenocarcinoma component stained positive for MUC2, which suggests that the adenocarcinoma component originated from Barrett's epithelium. Taken together, the neuroendocrine carcinoma may have originated from Barrett's epithelium. A metastasis to the liver was found 2 months after the surgical resection. Chemotherapy was administered, but there was no response. Most esophageal neuroendocrine carcinomas are accompanied by adenocarcinoma or squamous cell components, suggesting that these carcinomas originate from pluripotent cells in squamous or Barrett's epithelium. Appropriate chemotherapy for these lesions should be considered based on the cell of origin.

BACKGROUND: Intestinal ischemia/reperfusion (I/R) injury is a life-threatening complication that leads to inflammation and remote organ damage. However, the underlying mechanism is not yet fully understood. Toll-like receptor 5 (TLR5) is highly expressed in mucosa and recognizes flagellin, the main component of the bacterial flagella. Here, we investigated the role of TLR5 in inflammation and tissue damage after intestinal I/R injury using TLR5-deficient mice. METHODS AND RESULTS: Intestinal levels of TLR5 mRNA and flagellin protein were elevated in wild-type mice subjected to intestinal I/R. Although TLR5 deficiency had no effect on intestinal flagellin levels, it significantly attenuated intestinal injury and inflammatory responses after intestinal I/R. TLR5 deficiency also markedly improved survival in mice after intestinal I/R injury. In wild-type mice, intestinal I/R injury induced remote organ damage, particularly in the lung, which was attenuated by TLR5 deficiency. Furthermore, TLR5 deficiency prevented lung inflammatory responses and vascular permeability after intestinal I/R injury. CONCLUSION: These findings demonstrate a novel role of TLR5 and provide new insights into the mechanism underlying inflammation and tissue damage after intestinal I/R injury.

BACKGROUND: Primary sarcoma of the breast is rare. Surgery has been the only curative treatment available. Recently, neoadjuvant chemotherapy including anthracycline/ifosfamide has been reported effective for patients with high-risk sarcomas in a prospective trial. CASE PRESENTATION: A 52-year-old Japanese woman presented with a mass in her left breast. The 10 cm tumor was fixed to her chest wall on examination. A skin biopsy was performed which showed leiomyosarcoma. Neoadjuvant chemotherapy was given and the tumor became mobile. A mastectomy and axillary dissection were performed with surgically negative margins. After neoadjuvant chemotherapy, the amount of necrosis was profoundly influenced by chemotherapy, and the histological effect of neoadjuvant chemotherapy was assessed in reference to pre-neoadjuvant chemotherapy magnetic resonance imaging. CONCLUSION: In contrast to many other cancers, the evaluation of various treatments and of the histological effect of neoadjuvant chemotherapy for sarcoma has been difficult due to the rarity of these tumors. We report the case of a patient with a breast sarcoma, treated with neoadjuvant chemotherapy and discuss the appropriate pathological evaluation and therapeutic management.

Gastrointestinal stromal tumors (GIST) in patients under 18 years of age are classified as pediatric GIST. Pediatric GIST are extremely rare, and there are no reports of laparoscopic-endoscopic cooperative surgery for these lesions. We report the use of non-exposed endoscopic wall-inversion surgery as a laparoscopic-endoscopic cooperative surgery-related procedure for the treatment of a pediatric GIST. The case involved a 17-year-old male patient who presented with anemia and was found to have a bleeding gastric tumor. The tumor was resected transorally using the non-exposed endoscopic wall-inversion surgery technique. No gene mutation of c-Kit or Platelet-Derived Growth Factor Receptor α (PDGFRα) was found, and the final pathological diagnosis was epithelial-type GIST due to a succinate dehydrogenase abnormality. Follow-up included a CT scan every 4 months. No recurrence has occurred to date.

OBJECTIVE: Mucin1 (MUC1), a member of the mucin family, is a glycoprotein which is often expressed in malignant cells. However, the expression and function of MUC1 in human duodenal adenocarcinoma (DAC) has not yet been characterized because of its low frequency. Here, we examined the functional roles of core protein (MUC1-C) in DAC. MATERIALS AND METHODS: Using a human duodenal cancer cell line, HuTu80, proliferation, migration, invasion, ALDH activity was assessed by cell counting kit-8, scratch wound healing, matrigel invasion, and ALDEFUOR assays, respectively. The function of MUC1 protein was evaluated with knockdown using specific siRNA as well as anti-MUC1-C peptide, GO203. MUC1 expression in human DAC was evaluated immunohistochemically in surgically resected tumors. RESULTS: The positive expression of MUC1 in HuTu80 was confirmed by RT-PCR and flow cytometry. In vitro cell growth was inhibited by the addition of 50-100 μM GO203 as well as treatment with siRNA for MUC1-C. Silencing of MUC1-C also significantly reduced migration, invasion, ALDH activity. Local injection of GO-203 (14 mg/kg) significantly suppressed the growth of subcutaneous HuTu80 tumors in nude mice. Immunohistochemically, MUC1 was strongly detected in seven DAC cases, but not in 11 others. The outcome of patients with high MUC1 expression was significantly worse than those without MUC1 expression. CONCLUSIONS: These results suggest that MUC1 is functionally associated with the malignant potential of DAC and could be a novel therapeutic target for this rare tumor.

INTRODUCTION: Immune thrombocytopenic purpura is an acquired thrombocytopenia. Preoperative management of thrombocytopenia is important in patients with gastric cancer. Partial splenic embolization can be effective for patients with thrombocytopenia, but could lead to ischemic necrosis of the remnant stomach when performing subtotal gastrectomy with splenectomy. PRESENTATION OF CASE: The patient is an 84-year old woman evaluated for anemia. Endoscopy revealed an advanced gastric cancer with bleeding. The patient also had immune thrombocytopenic purpura with a platelet count <50,000/μL. Administration of platelets did not increase the platelet count. Partial splenic embolization was performed followed by administration of high-dose immunoglobulin. The platelet count was over 50,000/μL preoperatively. The patient underwent combined subtotal gastrectomy and splenectomy, followed by an uneventful course. DISCUSSION: Patients with immune thrombocytopenic purpura and advanced gastric cancer can have anemia. Partial splenic embolization has been used to treat patients with refractory immune thrombocytopenic purpura as an alternative to splenectomy. Preoperative partial splenic embolization and high-dose immunoglobulin therapy resulted an increased platelet count in this patient. Elderly patients with gastric cancer have a high risk of postoperative complications. Patients with gastric cancer undergoing total gastrectomy have an impaired postoperative quality of life compared to those who undergo subtotal gastrectomy. We performed a subtotal gastrectomy and splenectomy as a function-preserving operation, completed safely by maintaining blood flow to the remnant stomach. CONCLUSION: Partial splenic embolization is effective for patients with immune thrombocytopenic purpura and gastric cancer. Combined subtotal gastrectomy and splenectomy is achieved by preserving blood flow to the remnant stomach.

INTRODUCTION: Gastric hyperplastic polyps are common stomach lesion and these polyps are generally benign. However, they can undergo malignant transformation. Most reported cases of malignant transformation of gastric hyperplastic polyps have been to well or moderately differentiated adenocarcinoma, and those transformed into poorly differentiated adenocarcinoma are extremely rare. No case has been reported that has changed to diffuse type adenocarcinoma with lymphatic invasion. PRESENTATION OF CASE: A 48-year-old woman presented with worsening anemia. A polyp was seen in the gastric cardia seven years prior to presentation. Helicobacter pylori infection was also found at that time. She underwent upper gastrointestinal endoscopy and biopsy of the polyp revealed signet ring cell carcinoma. Total gastrectomy was performed due to concern about possible invasion into the submucosal layer and there was no evidence of distant metastases. Histologic examination revealed both poorly differentiated adenocarcinoma and signet ring cell carcinoma surrounded by hyperplastic epithelium at the head of the polyp. Lymphatic invasion was also found, and malignant cells were limited to the mucosa. DISCUSSION: Gastric hyperplastic polyps are commonly associated with chronic gastritis which is related to Helicobacter pylori infections. Gastric hyperplastic polyps are generally benign and rarely undergo malignant transformation to adenocarcinoma with differentiated histology. The gastric hyperplastic polyp in this patient transformed to poorly differentiated adenocarcinoma with lymphatic invasion. CONCLUSION: Even small polyps may become poorly differentiated adenocarcinoma with invasion, so close follow-up or endoscopic resection are recommended as well as eradication of Helico Pylori infection when appropriate.

Activated neutrophils release neutrophil extracellular traps (NETs), which can capture and destroy microbes. Recent studies suggest that NETs are involved in various disease processes, such as autoimmune disease, thrombosis, and tumor metastases. Here, we show a detailed in vitro technique to detect NET activity during the trapping of free tumor cells, which grow after attachment to NETs. First, we collected low density neutrophils (LDN) from postoperative peritoneal lavage fluid from patients who underwent laparotomies. Short-term culturing of LDN resulted in massive NET formation that was visualized with green fluorescent nuclear and chromosome counterstain. After co-incubation of human gastric cancer cell lines MKN45, OCUM-1, and NUGC-4 with the NETs, many tumor cells were trapped by the NETs. Subsequently, the attachment was completely abrogated by the degradation of NETs with DNase I. Time-lapse video revealed that tumor cells trapped by the NETs did not die but instead grew vigorously in a continuous culture. These methods may be applied to the detection of adhesive interactions between NETs and various types of cells and materials.

Purpose Intraperitoneal paclitaxel plus systemic chemotherapy demonstrated promising clinical effects in patients with gastric cancer with peritoneal metastasis. We aimed to verify its superiority over standard systemic chemotherapy in overall survival. Patients and Methods This randomized phase III trial enrolled patients with gastric cancer with peritoneal metastasis who had received no or short-term (< 2 months) chemotherapy. Patients were randomly assigned at a two-to-one ratio to receive intraperitoneal and intravenous paclitaxel plus S-1 (IP; intraperitoneal paclitaxel 20 mg/m2 and intravenous paclitaxel 50 mg/m2 on days 1 and 8 plus S-1 80 mg/m2 per day on days 1 to 14 for a 3-week cycle) or S-1 plus cisplatin (SP; S-1 80 mg/m2 per day on days 1 to 21 plus cisplatin 60 mg/m2 on day 8 for a 5-week cycle), stratified by center, previous chemotherapy, and extent of peritoneal metastasis. The primary end point was overall survival. Secondary end points were response rate, 3-year overall survival rate, and safety. Results We enrolled 183 patients and performed efficacy analyses in 164 eligible patients. Baseline characteristics were balanced between the arms, except that patients in the IP arm had significantly more ascites. The median survival times for the IP and SP arms were 17.7 and 15.2 months, respectively (hazard ratio, 0.72; 95% CI, 0.49 to 1.04; stratified log-rank P = .080). In the sensitivity analysis adjusted for baseline ascites, the hazard ratio was 0.59 (95% CI, 0.39 to 0.87; P = .008). The 3-year overall survival rate was 21.9% (95% CI, 14.9% to 29.9%) in the IP arm and 6.0% (95% CI, 1.6% to 14.9%) in the SP arm. Both regimens were well tolerated. Conclusion This trial failed to show statistical superiority of intraperitoneal paclitaxel plus systemic chemotherapy. However, the exploratory analyses suggested possible clinical benefits of intraperitoneal paclitaxel for gastric cancer.

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Despite recent advances in chemotherapy, outcomes of patients with peritoneal metastases (PM) from gastric cancer are still very poor and standard treatment has not been established. Although oral S-1 appears to be effective for patients with PM, the effects of systemic chemotherapy are limited. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) yield fewer benefits in patients with PM from gastric cancer than in patients with PM from other malignancies. In comparison, repeated intraperitoneal chemotherapy (RIPEC) with taxanes using an implantable peritoneal access port has a pharmacokinetic advantage for the control of peritoneal lesions and in combination with systemic chemotherapy can result in surprisingly long-term survival in patients with PM from gastric cancer. Herein, we review the results of recent clinical studies specifically targeting PM from gastric cancer and discuss future prospects for an intraperitoneal approach to the ideal treatment of patients with gastric cancer with peritoneal involvement.

Many types of immune cells appear in peritoneal cavity after abdominal surgery. In patients who underwent laparotomy due to gastric cancer, peritoneal lavages were obtained before and after surgical procedure. Cells were recovered from intermediate layer after Ficoll-Hypaque centrifugation and analyzed for phenotypes and functions, especially focused on low density neutrophils (LDN). The number of CD66b (+) LDN with mature phenotype was markedly elevated in postoperative as compared with preoperative lavages. Short term culture of the purified LDN produced many threadlike structures positive for SYTOX, nucleic acid staining, as well as histone and myeloperoxidase, suggesting the NETs formation. Human gastric cancer cells, MKN45, OCUM-1 and NUGC-4, were selectively attached on the NETs, which was totally abolished by the pretreatment of DNAse I. Intraperitoneal (IP) co-transfer of the LDN with MKN45 in nude mice strongly augments the metastasis formation on peritoneum, which was strongly suppressed by the following IP administration of DNAse I. Many NETs-like structures were detected on the surface of human omental tissue resected by gastrectomy. NETs on peritoneal surface can assist the clustering and growth of free tumor cells disseminated in abdomen. Disruption of the NETs by DNAse might be useful to prevent the peritoneal recurrence after abdominal surgery.

INTRODUCTION: Black adrenal adenoma (BAA) is a rare, benign adrenal lesion with a black or brown appearance. This is the first report of this lesion in a patient with a synchronous esophageal cancer and highlights the importance of considering a false positive finding on a Positron Emission Tomography (PET) scan, which might otherwise preclude resection. PRESENTATION OF CASE: A 73-year-old male was diagnosed with mid-esophagus carcinoma. Computed tomography scan revealed an enlarged left adrenal gland. Plasma adrenocorticotropic hormones levels were normal. To characterize the adrenal lesion, a PET scan was obtained which showed high uptake of 18F-fluoro-2-deoxy-d-glucose (FDG), consistent with a metastasis, suggesting T3N2M1, clinical stage IV esophageal cancer. After two courses of neo-adjuvant therapy, sub-total esophagectomy and left adrenalectomy were performed. The adrenal tumor was soft, and black in color, diagnosed as a BAA on histology. The pathologic stage of the esophageal cancer was T3N0M0, Stage II. Six months after surgery, he is alive without recurrence. DISCUSSION: High FDG uptake by an adrenal lesion on PET scan, as in this patient, usually suggests a metastatic lesion. Although rare, patients with esophageal cancer and adrenal metastases have been reported to have long-term survival, so it is important to characterize an adrenal lesion when found. CONCLUSION: Most adrenal lesions with high FDG uptake are malignant, but BAA is also positive on PET scan. Although rare, BAA should be considered in patients with solitary adrenal lesions with high uptake on PET scan, even in the presence of a malignancy.

INTRODUCTION: Gastric leiomyomas are benign mesenchymal tumors, comprising about 2.5% of gastric neoplasms, which can be difficult to differentiate from gastrointestinal stromal tumors which have malignant potential. Granular cell tumors in the abdominal wall are also rare. Since mesenchymal tumors are difficult to diagnose by imaging, further studies are needed to establish the diagnosis. PRESENTATION OF CASE: A 60-year-old asymptomatic woman underwent routine upper endoscopy and was found to have a gastric submucosal lesion. Computed tomography scan also showed an abdominal wall mass. The appearance of both lesions on imaging studies were similar, but it was unclear if the two lesions had the same origin. Endoscopic ultrasound-guided fine needle aspiration biopsy of the gastric lesion was insufficient to establish the diagnosis. Laparoscopic-endoscopic cooperative resection of the gastric lesion and ultrasound-guided core-needle biopsy of the abdominal wall mass enabled pathological diagnosis of both lesions. DISCUSSION: Diagnostic imaging findings of these two lesions were similar. Histologic and immunohistochemical studies are essential to establish a definitive diagnosis. Laparoscopic-endoscopic cooperative surgery may be an effective minimally invasive approach, allowing both pathological diagnosis and complete resection of a gastric submucosal tumor, especially when endoscopic-ultrasound guided fine needle aspiration or biopsy fails to make the diagnosis. CONCLUSION: Laparoscopic-endoscopic cooperative surgery can be an effective minimally invasive approach to resect some lesions. This is first report of the patient with a synchronous gastric leiomyoma and an intramuscular granular cell tumor in the abdominal wall.

BACKGROUND: Computed tomographic colonography (CTC) is reported to be feasible for screening of colorectal polyps; however, its efficacy in preoperative workup remains unknown. This study was done to define our CTC methodology and assess CTC's potential for preoperative examination in patients with colon cancer. METHODS: A total of 86 colon cancer patients underwent CTC prior to laparoscopic colectomy in our department from February 2014 to November 2015. The location of primary colon cancer determined by CTC was compared with that confirmed during the surgery. CTC was performed just after preoperative colonoscopy; for a small colon cancer, we performed clipping during colonoscopy to enhance CTC detectability. We classified wall deformities and compared them with the pathological T stage. RESULTS: CTC accurately located all 87 primary colon cancers prior to surgery. No patient experienced complications associated with CTC. The deformity classification correlated significantly with the pathological T stage (p < 0.001, Kruskal-Wallis nonparametric tests). CTC provided reconstructed images depicting the feeding artery of the primary colon cancer; feeding artery information obtained by CTC facilitated precise lymph node dissection. CONCLUSION: CTC appears to be a feasible and useful preoperative examination modality for colon cancer treatment.

BACKGROUND: The outcome of gastric cancer patients with peritoneal metastasis remains poor. We treated these patients with intraperitoneal and intravenous paclitaxel plus oral S-1 (tegafur/gimeracil/oteracil), followed by gastrectomy in responders. We evaluated the clinical significance of peritoneal lavage carcinoembryonic antigen (CEA) messenger RNA (mRNA) levels as a biomarker for indication of conversion gastrectomy. METHODS: The peritoneal lavage of 68 patients who received the above regimen as induction chemotherapy was repeatedly collected via intraperitoneal access ports. Gastrectomy was considered when improvement of peritoneal metastasis was confirmed by a second laparoscopic examination with negative peritoneal cytology. CEA and porphobilinogen deaminase mRNAs were chronologically quantified using the transcription reverse-transcription concerted reaction method. The CEA mRNA index (CmRI) was calculated as CEA mRNA/porphobilinogen deaminase mRNA × 10,000. RESULTS: Thirty-nine patients underwent gastrectomy and 29 patients did not (median survival time, 27.8 vs. 10.7 months, respectively; P < 0.001). In gastrectomy-positive patients, the outcome largely differed according to CmRI values immediately prior to surgery. Patients with a preoperative CmRI value <100 (n = 20) were associated with a significantly longer survival than those with a preoperative CmRI value >100 (n = 19) (41.8 vs. 20.1 months, respectively; P < 0.001). A preoperative CmRI value <100 was confirmed as an independent predictor of survival for gastrectomy-positive patients in the multivariate analysis. CONCLUSIONS: The CmRI reflects the response of peritoneal metastases to induction intraperitoneal chemotherapy. It may be a useful biomarker for indicating gastrectomy in gastric cancer patients with peritoneal metastasis.

BACKGROUND: Patients with esophageal cancer and a history of gastrectomy or concurrent gastric cancer undergo not only esophagectomy but also total gastrectomy. The goal of this study is to evaluate the postoperative quality of life (QOL) and dysfunction of these patients using two postoperative questionnaires. MATERIALS AND METHODS: From 1999 to 2015, 41 patients underwent concurrent esophagectomy and total gastrectomy. A jejunal pedicle with the subcutaneous supercharge technique was used for reconstruction. Patients were divided into two groups, including those undergoing concurrent esophagostomy and gastrectomy (Group 1), and those undergoing esophagectomy alone (Group 2, history of previous gastrectomy). Patients were analyzed by time interval, including patients within three years of surgery (Group A) and those more than three years after surgery (Group B). RESULTS: Eighteen patients completed the questionnaires. The mean DAUGS20 score was 26.4 ± 13.2. The DAUGS20 scores of groups 1 (N = 7) and 2 (N = 11) were 25.4 ± 12.5 and 27 ± 15.4 (p = 0.58), respectively. Global health status scored by the EORTC QLQC-30 were 71.4 ± 18.5 in group 1 and 67.4 ± 22.8 in group 2 (p = 0.85). DAUGS20 scores of group A (N = 10) and B (N = 8) were 28.1 ± 12.4 and 23.3 ± 14.4 (p = 0.35). No significant differences were found between groups A and B regarding the QLQ-C30 scores. CONCLUSION: DAUGS20 and QLQ-C30 scores showed no significant differences between groups 1 and 2 or groups A and B. These results suggest that postoperative QOL and dysfunction may be influenced more by current status than by surgical history and postoperative interval. Previous reports describe a DAUGS 20 score after gastrectomy of 27.8 and after esophagectomy of 36.1. The DAUGS20 score of these 18 patients is lower than DAUGS20 scores for patients undergoing either operation alone. Reconstruction using a subcutaneously placed jejunal segment seems to be reasonable.

Intraperitoneal administration of chemotherapeutics is expected for the treatment of peritoneally disseminated gastric cancer because of poor migration of the drugs from the systemic circulation to the peritoneal cavity. In this study, for intraperitoneal delivery of cisplatin (CDDP), we developed a hyaluronan (HA)-based hybrid system in which CDDP-loaded HA nanogels were either physically encapsulated in or chemically conjugated to injectable HA hydrogels. Physical encapsulation enabled sustained release of HA nanogels from the HA hydrogel matrix for over a week. This was a longer release period than that of encapsulated free CDDP, which released 80% of the drug in 2 days. The longer release was attributed to delayed diffusion of HA nanogels from the hydrogel matrix network. The release profile could be tuned by modifying the chemical conjugation of HA nanogels to the HA hydrogel matrix, as well as the type of chelating ligands used to load CDDP to the nanogel. Furthermore, intraperitoneally administered hybrid had significant antitumor activity in a mouse model of peritoneally disseminated gastric cancer, especially for nodules smaller than 1.0 mm.

Background: Repeated intraperitoneal (IP) administration of paclitaxel (PTX) with concurrent systemic chemotherapy is clinically effective for the treatment of peritoneal metastases (PM) from gastric cancer. However, it is unclear how biochemical modifications may affect the pharmacokinetics and bioavailability of IP administered PTX. Methods: In a xenograft PM model using human gastric cancer cells, MKN45, fluorescein-conjugated PTX (OG-PTX) was given IP and the intra-tumor distribution of PTX examined with fluorescein microscopy. Results: After IP injection, PTX was seen to directly infiltrate up to several hundred micrometers from the surface of the PM. Co-injection with 5 % non-animal stabilized hyaluronic acid increased PTX infiltration and suppressed the development of PM more efficiently than PTX alone. PTX solubilized with amphiphilic polymer composed of 2-methacryloyloxyethyl phosphorylcholine (MPC) and n-butyl methacrylate (BMA) efficiently formed a micellar formation 50-100 nm in diameter. IP injection of the nanomicellar PTX (PTX-30W) also showed significantly enhanced tumor infiltration and further inhibition of the growth of PM compared with PTX solubilized with Cremophor-ethanol (PTX-Cre). Finally, IP administration of NK105, another nanomicellar PTX, inhibited the growth of subcutaneous tumors as well as PM, compared with conventional PTX-Cre in the same murine model. Conclusions: PTX administered IP directly infiltrates PM and are thus a useful strategy for the treatment of PM. Drug modification with nanotechnology may further enhance penetration of PM resulting in improved clinical efficacy.