倉科 憲太郎

Peritoneal dissemination is a major metastatic pathway for gastrointestinal and ovarian malignancies. The miR-29b family is downregulated in peritoneal fluids in patients with peritoneal metastases (PM). We examined the effect of miR-29b on mesothelial cells (MC) which play critical a role in the development of PM through mesothelial-mesenchymal transition (MMT). Human peritoneal mesothelial cells (HPMCs) were isolated from surgically resected omental tissue and MMT induced by stimulation with 10 ng/ml TGF-β1. MiR-29b mimics and negative control miR were transfected by lipofection using RNAiMAX and the effects on the MMT evaluated in vitro. HPMC produced substantial amounts of miR-29b which was markedly inhibited by TGF-β1. TGF-β1 stimulation of HPMC induced morphological changes with decreased expression of E-cadherin and calretinin, and increased expression of vimentin and fibronectin. TGF-β1 also enhanced proliferation and migration of HPMC as well as adhesion of tumor cells in a fibronectin dependent manner. However, all events were strongly abrogated by simultaneous transfection of miR-29b. MiR-29b inhibits TGF-β1 induced MMT and replacement of miR-29b in the peritoneal cavity might be effective to prevent development of PM partly through the effects on MC.

Background: The peritoneal cavity contains many site-specific immune cells which constitute a unique immune microenvironment. However, it is unclear how the local immune signature is altered in patients with peritoneal metastases (PM). Methods: Peritoneal lavage fluid or ascites were obtained from 122 patients with various stages of gastric cancer (GC). Cells recovered from peritoneal fluids were immunostained with mAbs for lymphocyte-, macrophage- and tumor cell-specific antigens and the frequencies of leukocyte subsets and antigen expression levels were evaluated with multi-color flowcytometry. Results: The proportions of CD8(+) T cells, CD3(+)CD56(+) NKT-like cells, and CD3(-)CD56(+) NK cells to CD45(+) leukocytes were significantly reduced in patients with PM compared to those without PM. In patients with PM, the rates of CD8 (+) T cells and NKT-like cells correlated inversely with the tumor leukocyte ratio (TLR), the relative frequency of CD326(+) tumor cells to CD45(+) leukocytes. In contrast, the proportion of CD19(+) B cells was significantly increased in patients with PM, and their proportion correlated positively with the TLR and peritoneal carcinomatosis index (PCI) score. In patients with PM, CD14(+) macrophages tended to be increased with enhanced expression of CD14, CD16 and a M2-macrophage marker, CD163. In particular, macrophages in patients with high TLR contained many granules with high side scatter and CD14 expression in their flow profile compared to those without PM. Conclusion: PM are accompanied by a drastic change in phenotypes of lymphocyte and macrophage in the peritoneal cavity, which might be involved in the development and progression of intraperitoneal tumor growth.

BACKGROUND: Leiomyosarcoma is a rare tumor that could originate from the gastrointestinal tract, uterus, kidney, retroperitoneum, and the soft tissues of the extremities. It accounts for only 1% of all gastrointestinal mesenchymal tumors and primary leiomyosarcoma of the stomach is extremely rare. Most cases reported as leiomyosarcoma of the stomach before the development of KIT immunohistochemistry might be gastrointestinal stromal tumors (GISTs) of the stomach and only 18 cases of leiomyosarcoma of the stomach have been reported since early 2000s. We report here a patient with leiomyosarcoma of the stomach treated by laparoscopic and endoscopic cooperative surgery (LECS). CASE PRESENTATION: A 59-year-old man was referred to our hospital for an early gastric cancer, which was initially treated by endoscopic submucosal dissection. Six months after his initial treatment, a follow-up esophagogastroduodenoscopy revealed a small polypoid lesion at the lesser curvature of the proximal stomach, which appeared to be a hyperplastic polyp. However, one and a half years later, the lesion grew and showed more irregular surface. Biopsy at the time revealed smooth muscle cell proliferation suggestive of leiomyoma. Three years later, the lesion grew even larger and biopsy showed pleomorphic spindle cells. Immunohistochemical study showed positive staining for alpha-smooth muscle actin and desmin, but negative for c-kit and CD34. Ki-67 labeling index was nearly 60%. Based on these findings, the diagnosis of leiomyosarcoma was established. The patient subsequently underwent a partial gastrectomy by LECS. The patient is currently in good condition without recurrence or metastasis at 12 months after surgery. CONCLUSIONS: Leiomyosarcoma of the stomach is extremely rare. This is the first report of leiomyosarcoma of the stomach treated by LECS. We could also follow its appearance change through endoscopic examination for 3 years.

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: 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.

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.

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.

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.

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.

BACKGROUND: Decrease in appetite and weight after total gastrectomy in patients with gastric cancer leads to a decrease in quality of life, increased mortality, and may necessitate discontinuation of adjuvant chemotherapy. The aim of this study is to determine whether rikkunshito, a Japanese herbal medicine, increases food intake and weight after gastrectomy in rats. METHODS: Male rats underwent gastrectomy followed by roux-en-Y reconstruction or sham operation and were then treated with rikkunshito for 14 days starting on postoperative day 3. Daily food intake, weight, plasma glucagon-like peptide-1 (GLP-1), and ghrelin levels were measured. A pilot study to measure pre- and postoperative plasma GLP-1 levels was conducted in patients who underwent total gastrectomy for gastric cancer. RESULTS: Administration of rikkunshito after gastrectomy in rats significantly increased food intake and weight, which continued for at least 2 weeks after treatment. Both fasting and postprandial plasma GLP-1 levels were increased markedly after gastrectomy compared with sham-operated animals. Increased GLP-1 levels in rats after gastrectomy were suppressed markedly by rikkunshito. rikkunshito had no significant effect on plasma ghrelin levels after gastrectomy. Treatment with a GLP-1 receptor antagonist significantly improved food intake and weight after gastrectomy. Plasma fasting GLP-1 levels in patients with gastric cancer were increased greatly after gastrectomy on postoperative day 1. CONCLUSION: Administration of rikkunshito suppresses plasma GLP-1 levels after total gastrectomy, which is associated with recovery from reduced food intake and weight in rats.

INTRODUCTION: Spontaneous esophageal perforation, or Boerhaave's syndrome, is a life-threating condition which usually requires emergent surgery. An upside down stomach is defined as a gastric volvulus in a huge supradiaphragmatic sac. In general, this condition can result in ischemia and perforation of the stomach. This is the first report of a patient with Boerhaave's syndrome and an upside down stomach. CASE PRESENTATION: A 79-year-old woman presented with sudden epigastric pain following hematemesis. Evaluation of the patient showed both an esophageal perforation and an upside down stomach. Surgical drainage and irrigation of the mediastinum and pleural cavities were undertaken emergently. Due to the concurrent gastric volvulus, a gastrostomy was placed to fix and decompress the stomach. The patient had an uneventful hospital course and was discharged. DISCUSSION AND CONCLUSION: Boerhaave's syndrome is a rare but severe complication caused by excessive vomiting, due to a sudden elevation in intraluminal esophageal pressure resulting in esophageal perforation. Acute gastric volvulus can result in ischemia and perforation of the stomach, but has not previously been reported with esophageal perforation. The most likely mechanism associating an upside down stomach with Boerhaave's syndrome is acute gastric outlet obstruction resulting in vomiting, and subsequent esophageal perforation. Perforation of the esophagus as well as perforation of the stomach must be considered in patients with an upside down stomach although both upside down stomach and Boerhaave's syndrome are rare clinical entities.

© 2014 International Society for Diseases of the Esophagus. We retrospectively compared preoperative docetaxel, cisplatin, and fluorouracil (DCF) with cisplatin and fluorouracil (CF) in patients with esophageal cancer. The study included patients with advanced thoracic esophageal carcinoma (excluding T4 tumors) receiving preoperative chemotherapy. In the DCF group, five patients received two courses of treatment every 4 weeks, and 33 patients received three courses every 3 weeks. In the CF group, 38 patients received two courses of treatment every 4 weeks. Patients underwent curative surgery 4-5 weeks after completing chemotherapy. Patient demographic characteristics did not differ between the two study groups. The incidence of a grade 3 or 4 hematologic toxicity was significantly higher in the DCF group (33 patients) than in the CF group (five patients; P &lt; 0.001). Curative resection was accomplished in 79% of patients in the DCF group and 66% in the CF group (P = 0.305). There were no in-hospital deaths. The incidence of perioperative complications did not differ between the groups. A grade 2 or 3 histological response was attained in a significantly higher proportion of patients in the DCF group (63%) than in the CF group (5%; P &lt; 0.001). Progression-free survival and overall survival were significantly higher in the DCF group (P = 0.013, hazard ratio 0.473; P = 0.001, hazard ratio 0.344). In conclusion, a grade 3 or 4 hematologic toxicity was common in the DCF group but was managed by supportive therapy. Histological response rate, progression-free survival, and overall survival were significantly higher in the DCF group compared with the CF group.

BACKGROUND: The relationship between Helicobacter pylori infection and gastric cancer has been demonstrated, and the risk of gastric cancer occurrence is known to increase with the progression of atrophic changes associated with chronic gastritis. Endoscopic evaluation of the degree and extent of atrophy of the gastric mucosa is a simple and very important means of identifying a group at high risk for gastric cancer. This study aimed to clarify the carcinogenic risk in relation to the degree of atrophy. METHODS: A total of 27,777 patients (272 with early gastric cancer and 135 with advanced gastric cancer) were included in this study. Endoscopically evaluated atrophy of the gastric mucosa was classified as C-0 to O-3 according to the Kimura and Takemoto classification system. RESULTS: The cancer detection rate in relation to the degree of gastric mucosal atrophy was 0.04% (2/4,183 patients) for C-0, 0% (0/4,506) for C-1, 0.25% (9/3,660) for C-2, 0.71% (21/2,960) for C-3, 1.32% (75/5,684) for O-1, 3.70% (140/3,780) for O-2 and 5.33% (160/3,004) for O-3. As to the proportions of differentiated and undifferentiated cancers, the latter were relatively frequent in the C-0 to C-2 groups, but differentiated cancers became predominant as atrophy progressed. On the other hand, the number of both differentiated and undifferentiated cancers detected increased as gastric mucosal atrophy progressed. In addition, open-type atrophy was found in 29 (96.7%) of 30 patients with synchronous multiple gastric cancers and in all 20 patients with metachronous multiple gastric cancers. CONCLUSION: Endoscopic evaluation of gastric mucosal atrophy can provide a simple and reliable predictive index for both current and future carcinogenic risk.

BACKGROUND: The double-stapling technique (DST) for esophagojejunostomy using the transorally inserted anvil (OrVil; Covidien Japan, Tokyo, Japan) is one of the reconstruction methods used after laparoscopy-assisted total gastrectomy (LATG). This technique has potential advantages in terms of less invasive surgery without the need to create a complicated intraabdominal anastomosis. METHODS: From 2008 to 2011, 262 patients with gastric cancer underwent total gastrectomy and reconstruction with a Roux-en-Y anastomosis, and 52 patients underwent LATG with DST. A retrospective analysis then was performed comparing the patients who experienced postoperative stenosis after LATG-DST (positive group) and the patients who did not (negative group). A comparative analysis was performed among patients comparing conventional open total gastrectomy and LATG, and multivariate analysis was performed to evaluate risk factors for the development of anastomotic stenosis. RESULTS: A minor leak was found in 1 patient (1.9 %), and 11 patients experienced anastomotic stenosis (21 %) after LATG with DST. Among the patients with anastomotic stenosis, three (3/4, 75 %) anastomoses were performed with the 21-mm end-to-end anastomosis (EEA) stapler, and eight anastomoses were performed (8/47, 17 %) with the 25-mm EEA stapler. The median interval to the diagnosis of anastomotic stenosis was 43 days after surgery. The patients with stenosis needed endoscopic balloon dilation an average of four times, and the rate of perforation after dilation was 13 %. The clinical and operative characteristics did not differ between the two groups. Anastomotic stenosis after open total gastrectomy occurred in two cases (0.98 %). Multivariate analysis showed that the size of the EEA stapler and the use of DST were risk factors for anastomotic stenosis. CONCLUSION: Esophagojejunostomy using DST with OrVil is useful in performing a minimally invasive procedure but carries a high risk of anastomotic stenosis.

We report on a 53-year-old male with esophageal cancer. He had no evidence of distant metastasis, and received a subtotal esophagectomy. Histopathologically, the tumors were contiguous with Barrett's epithelium. Undifferentiated carcinoma components existed independently of differentiated adenocarcinoma components. Undifferentiated carcinoma was present proximal to the esophagogastric junction. Both tumors had invaded the submucosa and were associated with a prominent lymphoid stroma. Metastasis from undifferentiated carcinoma was found in the paraesophageal lymph nodes. Immunohistochemically, both components were negative for 34bE12 and positive for CAM5.2 and showed nearly identical staining patterns for p53, indicating that the tumors were derived from Barrett's epithelium. Because the undifferentiated carcinoma did not express CK20 or carcinoembryonic antigen, the properties of adenocarcinoma had apparently been lost during the process of tumor cell progression. This is the first report of undifferentiated carcinoma associated with Barrett's esophagus with adenocarcinoma.

OBJECTIVE: Adenosquamous carcinoma originating in the stomach is an unusual neoplasm with few existing histological studies. This study was aimed to gain insight into the histogenetic and clinicopathological characteristics of gastric cancer with squamous cell carcinoma (SCC) components. METHODS: From January 2001 to June 2010 a total of 1735 patients underwent a resection of gastric cancer. Histopathologically, eight patients had adenocarcinoma containing SCC components, in which the proportion of SCC components was above 25% of the total tumor mass in four patients. The immunohistochemical and clinicopathological characteristics of these eight patients were analyzed. RESULTS: The median survival duration was 22 months. Adenocarcinoma was present at the superficial layer of all tumors and SCC was primarily present at sites with deep invasion. Immunohistochemically, adenocarcinoma components were positive for cytokeratin (CK) 8/18/19 and CK7 in all cases. SCC components were positive for carcinoembryonic antigen and CK7 in more than 60% of patients. Expression patterns of p53 product were identical in both components. SCC components were positive for 34βE12 and adenocarcinoma components were negative for 34βE12 in all patients. CONCLUSIONS: SCC components are derived from squamous metaplasia in a pre-existing adenocarcinoma. A gastric adenocarcinoma with SCC components is associated with various patterns of metastasis and both SCC and adenocarcinoma components have the potential for metastasis. Gastric cancer with SCC components is a clinically aggressive tumor.

BACKGROUND: To decrease the incidence of internal hernia after laparoscopic gastric bypass, current recommendations include closure of mesenteric defects. Laparoscopic gastric resection is used increasingly for the treatment of gastric cancer, but the incidence of internal hernia in the treated patients has not been studied. METHODS: This study retrospectively reviewed 173 patients who underwent laparoscopic resection for gastric cancer at one institution, including distal and total gastric resections with antecolic Roux-en-Y reconstruction. RESULTS: An internal hernia occurred in 4 (7%) of 58 patients whose jejunojejunal mesenteric defect was not closed a mean of 326 days after surgery. All the patients underwent reoperation with reduction and repair of the hernia. In 115 subsequent cases, with closure of the mesenteric defect, internal hernias did not occur (0/115 cases; p < 0.05). CONCLUSION: Based on the current recommendations for patients undergoing bariatric surgery, closure of this potential hernia defect is mandatory after laparoscopic gastrectomy with a Roux-en-Y reconstruction for gastric cancer.

The patient is a 61-year-old man who had previously undergone an extended thymectomy for myasthenia gravis. Endoscopic examination during a routine follow-up visit revealed early gastric cancer in the proximal portion of the stomach. To undergo resection the patient received general and epidural anesthesia. The conditions were unfavorable for laparoscopic-assisted surgery because he had a body mass index of 33 and muscle relaxants could not be used. Pneumoperitoneum was induced with carbon dioxide, and the abdominal wall was lifted. An adequate working space was secured in the upper abdomen and proximal gastrectomy was successfully performed.