佐田 尚宏

BACKGROUND: Communicating accessory bile ducts are defined as ducts that communicate between major biliary channels but do not drain individual segments of the liver. The Couinaud Type A communicating accessory bile duct is a rare anomaly where an aberrant duct connects the right main hepatic duct to the common hepatic duct without segmental drainage. There are very few reports of this anomaly in the literature to date. CASE PRESENTATION: A 75-year-old male who died of ischemic heart disease donated his body for cadaveric dissection, which included careful attention to the anatomy of the hepatic hilum. During dissection, it was found that the right hepatic duct was duplicated and an accessory duct drained directly into the common hepatic duct. Although rare and difficult to visualize even with modern preoperative imaging techniques, sound knowledge of this rare anatomic variation is imperative to avoid inadvertent intraoperative biliary injuries which can lead to severe morbidity. CONCLUSIONS: An aberrant bile duct from the right hepatic duct to the common hepatic duct (Couinaud Type A) is an uncommon accessory bile duct that one must be aware of when performing complex hepatobiliary procedures such as right liver resection for living-related donation. Detailed preoperative imaging and careful dissection with anticipation of anomalous anatomy are of the utmost importance for the safe conduct of hepatic surgery.

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.

BACKGROUND: To explore best practices for acute cholecystitis, it is necessary to construct a system to assess the difficulty of laparoscopic cholecystectomy (LC) based on intraoperative findings. In this study, multiple evaluators assessed videos of LC to assemble a library of typical video clips for 25 intraoperative findings. METHODS: We have previously identified 25 items that contribute to surgical difficulty in LC. For each item, roughly 30-s video clips were submitted from videos of LC performed at member institutions. We then selected one typical video from the collected clips based on simple tabulation of the instances of agreement. Inter-rater agreement was assessed with Fleiss's κ and Gwet's agreement coefficient (AC). RESULTS: Except in the case of two assessment items ("edematous change" and "easy bleeding"), κ or AC significantly exceeded 0.5 and the typical videos were judged to be applicable. For the two remaining items, the evaluation was repeated after clarifying the definitions of positive and negative findings. Eventually, they were recognized as typical. The completed video clip library contains 31 clips and is divided into five categories (http://www.jshbps.jp/modules/project/index.php?content_id=13). CONCLUSIONS: This clip library may be highly useful in clinical settings as a more objective standard for assessing surgical difficulty in LC.

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.

Extrahepatic bile duct (EHBD) cancer is a devastating cancer, and more common in Asian countries than in Western countries. Histological grading continues to be a highly relevant factor in prognosis and management of many kinds of cancer, however no uniform histological grading system exists for EHBD cancer. Histological heterogeneity within tumors is a problem in the evaluation of EHBD cancer. We developed an EHBD histological grading scheme to evaluate tumor differentiation pattern, and statistically analyzed its relationship with prognosis. In the present study, 257 surgically resected EHBD cancers were reviewed and their histological glandular differentiation (HGD) pattern was scored, and then we summed up the most and second most predominant scores. These scores were statistically analyzed for their relationship with patient prognosis. Patients showed a trend of shortening recurrence-free survival (RFS) and overall survival (OS) in association with higher HGD scores. In multivariate analyses, HGD score was determined to be an influential factor in RFS (P = 0.00041) and OS (P < 0.0001). In addition, combining HGD score and lymph node status correctly stratified patient prognosis in RFS. In conclusion, this new HGD scoring system is highly practical and has powerful prognostic value for EHBD cancer.

The outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses serious health and economic problems worldwide. One of the worst scenarios is the collapse of the medical care system due to nosocomial infections. SARS-CoV-2 quickly spreads in closed spaces, crowded areas, and close physical distances, which frequently occur in Japanese medical facilities. Although we are making efforts to avoid such situations, healthcare workers always face the risk of developing a SARS-CoV-2 infection in the workplace because of proximity. Thus, we need to battle SARS-CoV-2 using a unique strategy. We propose a novel strategy to eliminate SARS-CoV-2 infections: measurement of antibodies against SARS-CoV-2 and using the power of "immune survivors." We agree with using standard precautions and early isolation of patients with coronavirus disease 2019 (COVID-19) to block the spread of SARS-CoV-2 infection. However, we face difficulties carrying out these fundamental missions. Now, we focus on "immune survivors." If healthcare workers acquired the neutralizing antibody against SARS-CoV-2, they are considered "immune survivors" with a low risk of reinfection with SARS-CoV-2. These "immune survivors" can contribute to the care of patients with COVID-19 on the front line. Also, these "immune survivors" can function as an envelope by surrounding COVID-19 patients. As a result, "immune survivors" can eliminate the spread of SARS-CoV-2 in medical facilities as well as in society. We understand that the concept of "immune survivors" needs further discussion. No information is available on how long or the titer of neutralizing antibody required for protection from infection. We have just started to measure antibody levels against SARS-CoV-2 in healthcare workers in our hospital. This project will provide further information in the battle against the SARS-CoV-2 infection. (Clinical trial registration number: UMIN 000039997).

74歳、女性。検診で便潜血検査陽性を指摘され当院を受診し、大腸内視鏡検査を施行した。挿入時にS状結腸の伸展を認め、挿入に2人の医師が関与した。盲腸までの挿入時間は43分であった。全大腸を観察し特に異常は認められなかった。検査後4日目に心窩部痛が出現し、10日目に下腹部痛が出現したため近医を受診。単純CTで骨盤内に腹水貯留を認めたため、精査加療目的に当科紹介となった。来院時、循環動態は安定しており、下腹部に軽度の自発痛および圧痛を認めた。腹部造影CTで脾周囲を中心に、肝表面、骨盤内に液体貯留を認め、脾臓下極の被膜損傷による腹腔内出血と診断した。循環動態は安定しており、モニタリングを行いながら保存的に経過を観察する方針とした。入院4日目の造影CTで腹腔内出血の増悪はなく、入院21日目に退院となった。大腸内視鏡検査後の脾損傷は、遅発性に出現することがあり、稀ではあるが留意すべき検査後合併症の一つである。(著者抄録)

＜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.

OBJECTIVES: Predicting the risk of posthepatectomy liver failure is important when performing extended hepatectomy. However, there is no established method to evaluate liver function and improve preoperative liver function in pediatric patients. MATERIALS AND METHODS: We show the clinical features of pediatric patients who underwent living donor liver transplant for posthepatectomy liver failure in hepatoblastoma. The subjects were 4 patients with hepatoblastoma who were classified as Pretreatment Extent of Disease III, 2 of whom had distal metastasis (chest wall and lung). RESULTS: Hepatic right trisegmentectomy was performed in 3 patients and extended left hepatectomy in 1 patient. The median alpha-fetoprotein level at the diagnosis of hepatoblastoma was 986300 ng/mL (range, 22500-2726350 ng/mL), and the median alpha-fetoprotein level before hepatectomy was 8489 ng/mL (range, 23-22500 ng/mL). The remnant liver volume after hepatectomy was 33.3% (range, 20% to 34.9%). Four patients had cholangitis after hepatectomy and progressed to posthepatectomy liver failure. The peak serum total bilirubin after hepatectomy was 11.4 mg/dL (range, 8.7-14.6 mg/dL). Living donor liver transplant was performed for these 4 patients with posthepatectomy liver failure, and they did not have a recurrence. CONCLUSIONS: When the predictive remnant liver volume by computed tomography-volumetry before extended hepatectomy for patients with hepatoblastoma is less than 40%, the possibility of posthepatectomy liver failure should be recognized.

Traumatic injury to the main pancreatic duct requires surgical treatment, but optimal management strategies have not been established. In patients with isolated pancreatic injury, the pancreatic parenchyma must be preserved to maintain long-term quality of life. We herein report a case of traumatic pancreatic injury with main pancreatic duct injury in the head of the pancreas. Two years later, the patient underwent a side-to-side anastomosis between the distal pancreatic duct and the jejunum. Eleven years later, he presented with abdominal pain and severe gastrointestinal bleeding from the Roux limb. Emergency surgery was performed with resection of the Roux limb along with central pancreatectomy. We attempted to preserve both portions of the remaining pancreas, including the injured pancreas head. We considered the pancreatic fluid outflow tract from the distal pancreatic head and performed primary reconstruction with a double pancreaticogastrostomy to avoid recurrent gastrointestinal bleeding. The double pancreaticogastrostomy allowed preservation of the injured pancreatic head considering the distal pancreatic fluid outflow from the pancreatic head and required no anastomoses to the small intestine.

A 41-year-old woman presented with a positive fecal occult blood test. Colonoscopy showed a 20mm, elastic, hard lesion at the appendiceal orifice. Abdominal computed tomography revealed a protruding lesion in the intestine. Laparoscopic ileocecal resection was performed. Histological examination showed endometrial glands in the muscularis propria, consistent with appendiceal endometriosis. We report a patient with appendiceal endometriosis with intussusception.

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.

We herein report a variant case of desmoplastic small round cell tumor (DSRCT) showing limited desmoplasia and confusing immunohistochemical findings. A 26-year-old male was referred for multiple abdominal masses. Laparoscopic biopsy showed only the solid proliferation of small round cells, and he was initially diagnosed with small cell carcinoma. At autopsy, the tumor spread diffusely throughout the abdominal and pelvic cavities. Although the tumor was composed of a predominantly solid pattern of small round cells, multiple samples revealed a fibrous stroma in limited areas only. While immunohistochemistry showed the diffuse expression of desmin, CD99, and bcl-2, epithelial differentiation was unclear with few cytokeratin-positive cells and no staining for the epithelial membrane antigen. Although fluorescence in situ hybridization analysis indicated the EWSR1 gene rearrangement, we were unable to exclude Ewing sarcoma considering the morphological and immunohistochemical findings. The diagnosis of DSRCT was confirmed with a reverse transcription-polymerase chain reaction for EWSR1-WT1 fusion transcripts. DSRCT must be included in a differential diagnosis of small round cell tumors even if desmoplasia is not immediately detected, and thorough sampling and a molecular analysis are mandatory.

BACKGROUND: Goblet cell carcinoid (GCC) is a neuroendocrine tumor usually found in the appendix. GCCs exhibit characteristic findings with mixed endocrine-exocrine features such as staining positive for neuroendocrine markers and producing mucin. The primary GCC of the rectum is exceedingly rare. CASE PRESENTATION: A 77-year-old Japanese male presented with hematochezia. Anal tenderness and a hard mass in the anal canal were found on the digital rectal examination, and colonoscopy was performed. Colonoscopy showed an irregularly shaped mass in the anal canal. Biopsy showed mixed features including adenocarcinoma in situ, well-differentiated adenocarcinoma, and mucinous carcinoma with invasive proliferation. No metastatic lesions were found on the computed tomography scan. Pelvic magnetic resonance imaging scan showed extramural growth of a tumor on the ventral side of the rectum without invasion to the prostate. Laparoscopic abdominoperineal resection was performed. The final diagnosis was well-differentiated adenocarcinoma in the mucosa and goblet cell carcinoid from the submucosa to the adventitia of the rectum. The patient was discharged from the hospital on postoperative day 16. Six months after resection, a computed tomography scan revealed multiple metastatic lesions in the liver. Several chemotherapy regimens were given, and the patient has stable disease 27 months after surgery. CONCLUSION: We present a patient with rectal GCC with metachronous liver metastases. Since GCC grows intramurally and is biologically aggressive compared to typical carcinoid lesions, the disease is usually diagnosed at an advanced stage. The development of optimal adjuvant chemotherapy is needed for those patients.

BACKGROUND: There have been no reports on the effectiveness of the administration of antithrombin III (AT III) for post-transplant portal vein thrombosis (PVT). We herein report a case of post-transplant PVT that was resolved by AT III treatment after living donor liver transplantation (LDLT). CASE PRESENTATION: The patient was a 57-year-old man who had been diagnosed with decompensate liver cirrhosis by hepatitis C virus infection. He presented with repeated hepatic coma and refractory ascites. Computed tomography (CT) revealed PVT of Yerdel classification grade II before LDLT. He underwent ABO-identical LDLT using a right lobe graft. A liver function test revealed elevated liver enzyme levels on post-operative day (POD) 14. The CT examination on POD 15 revealed PVT in the left side of the main portal vein at the side of left gastric vein ligation. AT III treatment from POD 15 to POD 24 was performed. Magnetic resonance imaging revealed that the PVT had decreased 10% on POD 27. Furthermore, AT III treatment from POD 28 to POD 32 was performed. The CT examination demonstrated the disappearance of PVT on POD 69 and thereafter, he had no recurrence of PVT on 10 post-operative month (POM). CONCLUSIONS: The present case suggests that the administration of AT III is safe and suitable for the treatment of post-transplant PVT.

BACKGROUND The number of pregnancies after liver transplantation (LT) is increasing; however, the safety and incidence of complications associated with these pregnancies are still unclear. In this report, we retrospectively assessed the influences and problems associated with post-transplant pregnancy on allografts, recipients, and fetuses. MATERIAL AND METHODS A total of 14 pregnancies were identified in 8 female recipients between 2005 and 2018. The original disease was biliary atresia in all recipients. We provide a basic guide for the management of planned pregnancies in female recipients. RESULTS Of the 7 planned pregnancies, no recipients took mycophenolate mofetil (MMF) or had allograft liver dysfunction. Among the 7 unplanned conceptions, we judged that the pregnancy was inadequate to continue in 4 recipients due to taking MMF and 2 recipients due to allograft liver dysfunction at conception. However, 4 recipients who immediately stopped taking MMF continued with their pregnancies. Ten pregnancies resulted in live 11 births. Among obstetric complications or fetal and neonatal complications, gestational diabetes mellitus in 3 recipients was the most common. There were 3 miscarriages and 1 planned termination because of MMF medication and liver dysfunction. CONCLUSIONS Planned pregnancies in LT recipients can lead to the birth of a healthy baby and no influence on either the allograft or the recipient. However, unplanned pregnancies in LT recipients, such as recipients who take MMF or have allograft liver dysfunction, may have an adverse influence on the fetus.

Hepatic ischemia-reperfusion (I/R) injury is a major problem in liver transplantation (LT). Although hepatocyte cell death is the initial event in hepatic I/R injury, the underlying mechanism remains unclear. In the present study, we retrospectively analyzed the clinical data of 202 pediatric living donor LT and found that a high serum ferritin level, a marker of iron overload, of the donor is an independent risk factor for liver damage after LT. Since ferroptosis has been recently discovered as an iron-dependent cell death that is triggered by a loss of cellular redox homeostasis, we investigated the role of ferroptosis in a murine model of hepatic I/R injury, and found that liver damage, lipid peroxidation, and upregulation of the ferroptosis marker Ptgs2 were induced by I/R, and all of these manifestations were markedly prevented by the ferroptosis-specific inhibitor ferrostatin-1 (Fer-1) or α-tocopherol. Fer-1 also inhibited hepatic I/R-induced inflammatory responses. Furthermore, hepatic I/R injury was attenuated by iron chelation by deferoxamine and exacerbated by iron overload with a high iron diet. These findings demonstrate that iron overload is a novel risk factor for hepatic I/R injury in LT, and ferroptosis contributes to the pathogenesis of hepatic I/R injury.

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.

BACKGROUND: Capicua transcriptional repressor (CIC) -rearranged sarcoma is characterized by small round cells, histologically similar to Ewing sarcoma. However, CIC-rearranged sarcoma has different clinical, histological, and immunohistochemical features from Ewing sarcoma. It is important to differentiate between these tumors. CASE PRESENTATION: The patient is a 44-year-old man with a duodenal tumor diagnosed in another hospital who presented with a history of melena. Laboratory studies showed anemia with a serum hemoglobin of 6.0 g/dL. He was hospitalized and gastrointestinal bleeding was controlled successfully with endoscopy. However, he suffered from appetite loss and vomiting and progression of anemia a few weeks after presentation. Upper gastrointestinal endoscopy showed a circumferential soft tumor in the second portion of the duodenum and the endoscope could not pass distally. Computed tomography scan showed a greater than 10 cm tumor in the duodenum, with compression of the inferior vena cava and infiltrating the ascending colon. A definitive pathologic diagnosis could not be established despite four biopsies from the tumor edge. Due to gastrointestinal obstruction and progression of anemia, a pylorus-preserving pancreaticoduodenectomy with partial resection of the inferior vena cava and right hemicolectomy was performed as a complete tumor resection. The tumor was diagnosed as a CIC-rearranged sarcoma, but 2 months postoperatively local recurrence and distant metastases to the liver and lung were found. The patient died 3 months after surgery. CONCLUSIONS: Although the only definitive treatment for CIC-rearranged sarcoma is surgical resection, the CIC-rearranged sarcoma is highly malignant with a poor prognosis even after radical resection. More research is needed to establish optimal treatment strategies.

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.

Acetaminophen (APAP) overdose is a common cause of drug-induced acute liver failure. Although hepatocyte cell death is considered to be the critical event in APAP-induced hepatotoxicity, the underlying mechanism remains unclear. Ferroptosis is a newly discovered type of cell death that is caused by a loss of cellular redox homeostasis. As glutathione (GSH) depletion triggers APAP-induced hepatotoxicity, we investigated the role of ferroptosis in a murine model of APAP-induced acute liver failure. APAP-induced hepatotoxicity (evaluated in terms of ALT, AST, and the histopathological score), lipid peroxidation (4-HNE and MDA), and upregulation of the ferroptosis maker PTGS2 mRNA were markedly prevented by the ferroptosis-specific inhibitor ferrostatin-1 (Fer-1). Fer-1 treatment also completely prevented mortality induced by high-dose APAP. Similarly, APAP-induced hepatotoxicity and lipid peroxidation were prevented by the iron chelator deferoxamine. Using mass spectrometry, we found that lipid peroxides derived from n-6 fatty acids, mainly arachidonic acid, were elevated by APAP, and that auto-oxidation is the predominant mechanism of APAP-derived lipid oxidation. APAP-induced hepatotoxicity was also prevented by genetic inhibition of acyl-CoA synthetase long-chain family member 4 or α-tocopherol supplementation. We found that ferroptosis is responsible for APAP-induced hepatocyte cell death. Our findings provide new insights into the mechanism of APAP-induced hepatotoxicity and suggest that ferroptosis is a potential therapeutic target for APAP-induced acute liver failure.

The high expression of human equilibrative nucleoside transporter-1 (hENT1) and the low expression of dihydropyrimidine dehydrogenase (DPD) are reported to predict a favorable prognosis in patients treated with gemcitabine (GEM) and 5-fluorouracil (5FU) as the adjuvant setting, respectively. The expression of hENT1 and DPD were analyzed in patients registered in the JASPAC 01 trial, which showed a better survival of S-1 over GEM as adjuvant chemotherapy after resection for pancreatic cancer, and their possible roles for predicting treatment outcomes and selecting a chemotherapeutic agent were investigated. Intensity of hENT1 and DPD expression was categorized into no, weak, moderate or strong by immunohistochemistry staining, and the patients were classified into high (strong/moderate) and low (no/weak) groups. Specimens were available for 326 of 377 (86.5%) patients. High expression of hENT1 and DPD was detected in 100 (30.7%) and 63 (19.3%) of 326 patients, respectively. In the S-1 arm, the median overall survival (OS) with low hENT1, 58.0 months, was significantly better than that with high hENT1, 30.9 months (hazard ratio 1.75, P = 0.007). In contrast, there were no significant differences in OS between DPD low and high groups in the S-1 arm and neither the expression levels of hENT1 nor DPD revealed a relationship with treatment outcomes in the GEM arm. The present study did not show that the DPD and hENT1 are useful biomarkers for choosing S-1 or GEM as adjuvant chemotherapy. However, hENT1 expression is a significant prognostic factor for survival in the S-1 arm.

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.

A 45-year-old man who presented with fever, polyarthritis and deafness was referred to our hospital, and given a diagnosis of granulomatosis with polyangiitis. Twelve days after starting corticosteroid and cyclophosphamide therapy, he suddenly developed abdominal pain. Abdominal CT scan showed an edematous small intestine with free air and fluid collection in the pelvis. Emergency laparotomy was performed for diagnosis of gastrointestinal perforation, which revealed 5-10 mm erythematous lesions at 20 sites on the anti-mesenteric side of the small intestine. Three of these lesions were perforated. Local resection with anastomosis were performed at each site. The postoperative course was uneventful, and medical treatment was resumed 9 days after the operation. Fifty-three days postoperatively, he developed abdominal pain again. Abdominal CT scan showed a partially-dilated small intestine with a small amount of ascites, suggesting a strangulated obstruction. Emergency laparotomy was performed, which showed edema at one of the previous anastomotic sites with a small amount of purulent ascites. There was no evidence of strangulation or perforation of the intestine. An omental patch was placed over the anastomotic site, and a drain placed in the pelvis. The postoperative course was uneventful, and he restarted medical treatment. Histopathology of the resected specimen showed vasculitis at the sites of perforation, suggesting a relationship with granulomatosis with polyangiitis. We report a patient with granulomatosis with polyangiitis with multiple perforations of the small intestine. Special attention should be paid for re-perforation in the treatment of the disease. Furthermore, medical information should be shared with patients and their families as well as medical staff.

INTRODUCTION: Metastases to the thyroid gland in patients with colorectal cancer are uncommon. We report a patient with rectal cancer who developed a metastasis to the thyroid gland. PRESENTATION OF CASE: The patient was a 45-year-old female five years status post rectal cancer resection. A thyroid lesion was detected on PET-CT scan with synchronous lung metastases. After pulmonary resection, a partial thyroidectomy was performed and pathological examination with immunohistochemical staining confirmed that the lesion was a metastasis from previous rectal cancer. She is free from recurrence two years after thyroid surgery. DISCUSSION: Colorectal metastases to the thyroid gland are usually seen with widespread disease, often with lung and liver metastases. The overall outcomes of previously reported patients with thyroid metastases were extremely poor, with most patients dying within months of diagnosis. Careful attention should be given to other sites of metastatic disease including the thyroid gland during postoperative follow-up. PET scan may be helpful to establish the diagnosis. CONCLUSION: Treatment decisions must be individualized, and depend on the presence of systemic disease. Selected patients may benefit from resection of metastases, and PET scan may be useful to identify patients who will benefit from resection.

BACKGROUND: Data describing the association of preoperative pulmonary function testing (PFT) with postoperative pulmonary complications (PPC) are inconsistent. We conducted this prospective study to determine the ability of PFT to predict PPC. MATERIALS AND METHODS: Data were prospectively collected from 676 patients who underwent elective abdominal surgery (emergency and thoracic operations excluded). The primary outcome was the occurrence of PPC within 30 days. Patient and procedure-related factors were examined as risk factors. Multivariate logistic regression analysis was performed using risk factors identified with univariate analysis and area under the curve (AUC) analysis performed. RESULTS: PPC occurred in 29 patients (4.9%). History of smoking or abnormal physical examination were not significantly associated. Multivariate analysis identified age (p = 0.03), operative time (p = 0.02), blood transfusions (p = 0.002), and %VC (p = 0.001) as significant risk factors. AUC with a model including age, operative time, and blood transfusion was 0.83. The addition of %VC to these three variables increased the AUC to 0.89 (p = 0.1). CONCLUSIONS: Age, operative time, blood transfusion, and %VC are significantly associated with an increased risk of PPC. The addition of %VC to other risk factors did not significantly improve the ability to predict PPC, showing that preoperative PFT is not helpful to predict PPC.

INTRODUCTION: Internal hernias are rare after laparoscopic colorectal resections. We report a patient with an internal hernia through a defect in the transverse mesocolon following laparoscopic resection. PRESENTATION OF CASE: A 52-year-old male underwent laparoscopic colectomy for transverse colon cancer and had an unremarkable postoperative course. Thirty days postoperatively, he presented to the emergency room with sudden onset abdominal pain and vomiting. Enhanced abdominal computed tomography scan showed strangulated small intestine in the left upper abdomen. An internal hernia through the mesenteric defect created during the recent colon resection was suspected, and emergency laparotomy was performed. One hundred thirty cm of small intestine was found herniated through a mesenteric defect. After repositioning the ischemic-appearing intestine, a 5 cm defect in the transverse mesocolon was found which had not been closed during the previous laparoscopic operation. No intestinal resection was needed, and the mesenteric defect closed with non-absorbable sutures. The post-operative course was unremarkable except for paralytic ileus, which resolved without further intervention. DISCUSSION: The incidence of internal hernia through a mesenteric defect after laparoscopic colorectal resection is quite low. Therefore, routine closure of the mesenteric defect after laparoscopic colorectal resection is not required. However, a left sided defect in the transverse mesocolon might be at higher risk of causing an internal hernia on anatomic grounds. CONCLUSION: We believe that mesenteric defects should be closed after laparoscopic resection of the left side of transverse colon, regardless of their size.