[Results of Surgical Treatment for Gastric Cancer in the Elderly Over 85 Years Old].

Although the number of gastric cancers in elderly is increasing with the aging population, the indications of surgical treatment depend on the individual cases and the decisions of doctors. We investigated the outcomes of gastrectomy in elderly patients aged 85 years and older who underwent surgery at our hospital. From 2014 to 2022, 72 cases of gastrectomy were performed in the elderly. The approaches were laparotomy in 28 cases, laparoscopic in 42, and robot-assisted in 2. There were 57 cases of distal gastrectomy, 7 cases of proximal gastrectomy, and 8 cases of total gastrectomy. The median operation time was 200 minutes, and the postoperative hospital stay was 14 days. There were 14 cases of complications of Grade Ⅱ or higher according to the Clavien-Dindo classification. Although intra-abdominal complications were not many, respiratory and circulatory complications were occasionally observed. The median follow-up period was 14.6 months, there were 10 deaths from other diseases. Risk factors for death from other diseases were laparotomy, postoperative complications, and outcomes other than discharging home. Although gastrectomy may be performed safely even in the elderly, it is important to pay attention to the patients' conditions particular to the elderly and to plan the surgery accordingly.

[A Case of Primary Somatostatin-Producing Tumor of the Duodenum with Liver Metastases with Long-Term Survival of More than 20 Years].

A 52-year-old woman underwent esophagogastroduodenoscopy after an abnormal medical examination, which revealed a mass lesion over half the circumference of the superior duodenal angulus. Immunostaining was diffusely positive for somatostatin, synaptophysin, and chromogranin A. A 3 cm-sized mass in the pancreaticoduodenal region and multiple nodular lesions of a few mm in both lobes of the liver were revealed by CT. The diagnosis is primary somatostatin-producing tumor of the duodenum with multiple liver metastases. She underwent gastric jejunal bypass for impaired transit. Afterwards hepatic infusion and systemic chemotherapy were continued, and 5 years passed without progression. When she stopped chemotherapy for 6 months, she started somatostatin analogue therapy because of the increase of the tumors. The tumors did not increase, and 20 years have passed since the start of treatment. We report a case of primary somatostatin-producing tumor of the duodenum with liver metastases that is still alive for a long period of time, with a review of the literature.

Gait improvement in stroke patients by Gait Exercise Assist Robot training is related to trunk verticality.

[Purpose] Various types of Gait Exercise Assist Robot (GEAR) have been developed recently, some of which have enabled early improvement in patients with stroke. However, none has yet resulted in independent walking in these patients. Hence, we conducted an exploratory study of the effect of GEAR on achieving independent walking in stroke patients. [Participants and Methods] The participants were 16 patients with severe stroke. We evaluated patients' ability to walk independently after GEAR training. The outcome measure was Stroke Impairment Assessment Set (SIAS) motor score (Hip Flexion, Knee Extension, Foot Pat, Abdominal and Verticality). Differences in five SIAS motor scores were compared between the independent and non-independent walking groups. [Results] There was statistically significant difference between the groups in terms of Verticality among the 5 SIAS items used in the present research . Verticality of SIAS score of 1 was the cut-off value for distinguishing walking independence. [Conclusion] Verticality of SIAS may be a marker of potential walking independence that can be used in rehabilitation plans using walking-assist robots in patients with stroke.

Clinical features of patients with pancreatic ductal adenocarcinoma with a history of other primary malignancies: A retrospective analysis.

Patients with pancreatic ductal adenocarcinoma (PDAC) that have a history of other primary malignancies are not well documented. The current study therefore aimed to evaluate the clinicopathological characteristics of patients with PDAC with or without a history of other primary malignancies. A total of 102 patients with surgically treated PDAC that presented with or without a history of other primary malignancies were retrospectively analyzed. A total of 25 patients (24.5%) had a history of other primary malignancies (age, with history of other primary malignancy vs. without, 74.2 vs. 68.9 years; P=0.005) and the reason for consultation (P<0.001) differed significantly between the groups with a history of other primary malignancies [HoM(+)] and without a history of other primary malignancies [HoM(-)]. Incidental indications during malignancy follow-up was the most common reason for the diagnosis of PDAC in the HoM(+) group. Conversely, there were no significant differences in the resectability (P=0.645), complete resection rate (P=0.774) and final stage (P=0.474) between the two groups. Disease-free survival was also not significantly different between the two groups (P=0.184). However, overall survival was significantly poorer in the HoM(+) group compared with the HoM(-) group (P=0.003). A history of other primary malignancies was also an independent predictor of poor overall survival (hazard ratio, 2.416; 95% confidence interval, 1.324-4.406; P=0.004). In conclusion, patients with PDAC and a history of other primary malignancies had significantly poorer overall survival than their counterparts, despite no differences in disease-free survival.

Thoracoscopic esophagectomy in the prone position for esophageal cancer patients with pectus excavatum: a report of two cases.

BACKGROUND: Pectus excavatum is a common thoracic deformity that can be encountered during thoracoscopic esophagectomy. Here, we report two cases of esophageal cancer complicated by pectus excavatum that were treated with thoracoscopic esophagectomy with the patients in the prone position. CASE PRESENTATION: The first patient was a 64-year-old male diagnosed with esophageal cancer (cT3N0M0, Haller index 8.5) and underwent radical thoracoscopic esophagectomy in the prone position following neoadjuvant chemotherapy. The second patient was a 67-year-old male diagnosed with esophageal cancer (cT1bN0M0, Haller index 4.3), and the same procedure was performed in this patient. In cases of patients with a high Haller index, where securing the surgical field is difficult, preoperative computed tomography in the prone position can help surgeons to understand the mediastinal field of view and is safe. CONCLUSIONS: Radical thoracoscopic esophagectomy in the prone position may be a surgical option in patients with pectus excavatum.

[Laparoscopy Assisted Subtotal Gastrectomy(Billrothâ Reconstruction)for Gastric Cancer in the Upper Stomach-A Report of Three Cases].

We experienced 3 cases of upper gastric cancer who underwent BillrothⅠ reconstruction in laparoscopy assisted subtotal gastrectomy. Two cases were female and 1 was male. The postoperative course was uneventful in all cases without heartburn, and the surgical margin was negative. The body weight loss rate was 5.8-12.6%, and the short-term results were relatively acceptable. Although the number of cases in this study was small, reconstruction with BillrothⅠ/delta-shaped anastomosis after laparoscopy assisted subtotal gastrectomy were considered to be useful.

Comparison of three fistula risk scores after pancreatoduodenectomy: A single-institution retrospective study.

BACKGROUND: Postoperative pancreatic fistula (POPF) after pancreatoduodenectomy greatly influences patients' postoperative course. Several evaluation methods have been used to assess the risk of clinically relevant POPF (CR-POPF) after pancreatoduodenectomy namely, the original, alternative, and updated alternative fistula risk scores (o-FRS, a-FRS, and ua-FRS, respectively). METHODS: We enrolled 106/179 patients who underwent pancreatoduodenectomy in our institution between April 2013 and Mar 2018. CR-POPF was defined as grade B and C POPF according to the 2016 definitions of the International Study Group on Pancreatic Surgery. RESULTS: Pancreatic gland texture was the only significant risk factor for CR-POPF (p = 0.007). The CR-POPF incidence increased significantly according to the risk groups defined by both o-FRS (p = 0.004) and a-FRS (p = 0.004). The area under the curve for o-FRS, a-FRS, and ua-FRS was 0.693, 0.693, and 0.671, respectively. CONCLUSION: o-FRS, a-FRS, and ua-FRS were almost equally useful for risk evaluation for CR-POPF after pancreatoduodenectomy. Further studies, especially for preoperative objective evaluation of pancreatic gland texture, are needed for more useful and accurate risk evaluation.

Safety and feasibility of laparoscopic and endoscopic cooperative surgery for duodenal neoplasm: a retrospective multicenter study.

BACKGROUND: A delayed perforation can often occur after endoscopic treatment for duodenal neoplasms and may be fatal due to leakage of pancreatic and bile juices. We aimed to evaluate the feasibility and safety of laparoscopic and endoscopic cooperative surgery for duodenal neoplasms (D-LECS) in a multicenter, retrospective study. METHODS: The clinical characteristics and surgical outcomes of 206 patients with duodenal neoplasms in whom D-LECS had initially been attempted at one of 14 institutions were reviewed retrospectively. RESULTS: Of the 206 patients, 63 (30.6 %), 128 (62.1 %), and 15 patients (7.3 %) had lesions at the bulb, second portion, and third portion of the duodenum, respectively. The rates of en bloc and R0 resections during D-LECS were 96.1 % and 95.1 %, respectively. Intraoperative and delayed perforations occurred in 10 (4.9 %) and 5 patients (2.4 %), respectively. No cases of recurrence were observed. Surgical duration of ≥ 180 minutes was an independent risk factor for postoperative complications. CONCLUSIONS: The results revealed that D-LECS was performed with oncological safety and technical feasibility.

[A Case of a Huge Gastrointestinal Stromal Tumor with Extraluminal Growth Arising in the Small Intestine Diagnosed as an Ovarian Tumor].

We report a case of a gastrointenstinal stromal tumor(GIST)of the small intestine with extraluminal growth that was difficult to distinguish from an ovarian tumor. A 73-year-old woman presented to a nearby hospital for lower abdominal pain. A computed tomography(CT)scan showed a 17 cm ovarian tumor in the pelvis, and she was referred to the gynecology department of our hospital. Following examinations(enhanced CT and magnetic resonance imaging), she was referred to our department in suspicion of a small intestinal GIST in which the superior mesenteric artery/vein was the feeding blood vessel, and intraperitoneal tumor resection was performed. A large cystic tumor occupied the abdominal cavity and was in contact with the small intestinal wall. As the tumor was not in contact with the uterus or bilateral adnexa, only partial resection of the small intestine was performed. Histopathological examination showed c-kit positivity and she was diagnosed with small intestinal GIST; as a result, a course of imatinib was started.

[A Case of Synchronous and Solitary Gallbladder Metastasis from Gastric Cancer].

A 60s woman was found to have wall thickening of the gastric body and gallbladder in the follow-up CT scan after surgery for cervical carcinoma. An endoscopic examination revealed a type 3 tumor, located in the lesser curvature of the middle stomach. Abdominal CT showed lymphadenopathy at the lesser curvature. An enhanced thickened wall was also noted in the fundus of the gallbladder. FDG-PET/CT showed negative uptake in the gallbladder lesion. Distal gastrectomy and cholecystectomy were performed under the preoperative diagnosis of gastric cancer and adenomyomatosis. Histopathologically, the gastric lesion was a poorly differentiated adenocarcinoma, SE, ly1c, v1b. Moreover, the gallbladder lesion was a poorly differentiated adenocarcinoma proliferating mainly in the muscularis propria and subserosa, which had similar histological features as those in the adenocarcinoma part of gastric cancer. From these findings, the patient was diagnosed with gallbladder metastasis from gastric cancer. Gastric cancer rarely metastasizes to the gallbladder, and only 16 cases have been reported in Japan. We present the clinicopathological features with a review of the literature.

A randomized controlled trial of postoperative intravenous acetaminophen plus thoracic epidural analgesia vs. thoracic epidural analgesia alone after gastrectomy for gastric cancer.

BACKGROUND: Acetaminophen is used in multimodal therapy for postoperative pain management. However, the additional effects of acetaminophen in combination with thoracic epidural analgesia (TEA) are not well understood. This prospective, multicenter randomized study was conducted to evaluate the efficacy of routine intravenous (i.v.) acetaminophen in combination with TEA for the management of postoperative pain in gastric cancer surgery. METHODS: A total of 120 patients who underwent distal gastrectomy were randomly assigned in a 1:1 ratio to receive i.v. acetaminophen every 6 h and TEA during the first 3 postoperative days (acetaminophen group) or TEA alone (control group). The primary endpoint was the sum of TEA rescue doses during the first 2 postoperative days. RESULTS: Final analysis included 58 patients in the acetaminophen group and 56 patients in the control group. The median number of TEA rescue doses was significantly lower in the acetaminophen group compared with the control group (3.0 vs. 8.0, p = 0.013). The median area under the curve (AUC) of the pain scores at coughing was significantly less in the acetaminophen group compared with the control group (285 vs. 342, p = 0.046) without an increase in postoperative complications. TEA rescue doses and pain score AUCs were significantly reduced by acetaminophen in patients who underwent open gastrectomy (p = 0.037 and 0.045), whereas there was no significant difference between patients who underwent laparoscopic gastrectomy in the two groups. CONCLUSIONS: In gastric cancer surgery patients, routine i.v. acetaminophen in combination with TEA provides superior postoperative pain management compared with TEA alone.

Multidisciplinary therapy for scirrhous gastric cancer: a retrospective analysis and proposal of new treatment strategy.

BACKGROUND: Scirrhous gastric cancer (SGC) is highly invasive and metastatic because of its interactions with stromal cells, such as fibroblasts and macrophages, and extracellular matrix, leading to a higher incidence of peritoneal metastasis (PM) than other gastric cancers (GCs). Taxane-based intraperitoneal chemotherapy (IPC) is a promising therapy for PM. We retrospectively analyzed outcomes of multidisciplinary therapies that included IPC for SGC. PATIENTS AND THERAPY: Of 1,679 GC patients treated between 1990 and 2012, we analyzed 119 patients who underwent multidisciplinary therapy for SGC. Patients without PM received gastrectomy with lymphadenectomy and resection of involved adjacent organs followed by intraoperative IPC using cisplatin. Patients with PM received chemotherapy using fluorouracil, with or without methotrexate plus IPC using cisplatin before 2000, and S-1 plus IPC using paclitaxel or docetaxel since 2000. RESULTS: Of the 119 patients, 73 (61%) had PM and 63 (53%) had positive peritoneal lavage cytology. Of the 89 gastrectomy patients, 30 (34%) had macroscopic residual tumors (R2). Of the patients treated since 2000, 66 (100%) received S-1 plus taxanes and 44 patients (67%) received taxane-based IPC. Median survival time was significantly longer in the post-2000 group (22.8 months) than in the pre-2000 group (9.5 months). In univariate analysis, lavage cytology, PM, taxane-based IPC, gastrectomy, and R2 resection were significant prognostic factors. However, only R2 resection was an independent prognostic factor in multivariate analysis (hazard ratio: 5.53, 95% CI: 2.05-14.93). CONCLUSION: As use of taxane-based IPC is not an independent prognostic factor, new multidisciplinary therapies are necessary to avoid R2 resections.

The effect of HIF-1α and PKM1 expression on acquisition of chemoresistance.

BACKGROUND: In patients with gastric cancer, one of the greatest obstacles to effective chemotherapy is the development of chemoresistance. It has been previously reported that hypoxia-inducible factor-1 alpha (HIF-1α) is associated with acquisition of chemoresistance, and more recent studies have also noted an association of pyruvate kinase muscle 1 (PKM1) and chemoresistance. The purpose of this study was to identify the effect of HIF-1α and PKM1 expression on the development of acquired chemoresistance using a paclitaxel (PTX)-resistant gastric cancer cell line. MATERIALS AND METHODS: A cancer cell line resistant to PTX was established from MKN45 cells by stepwise exposure to drug (rMKN45-PTX). The expressions of HIF-1α, apoptosis, vascular endothelial growth factor (VEGF), multidrug transporters and glycolytic enzyme were examined by Western blotting, enzyme-linked immunosorbent assay and immunohistochemistry. We also assessed the tumor proliferation by subcutaneous tumor and peritoneal dissemination of mouse xenograft model. RESULTS: The resistance index was 6.1 by determining as the ratio of the 50% growth inhibition (IC50) of rMKN45-PTX/IC50 of MKN45. Expression of nuclear factor kappa B and HIF-1α was increased in rMKN45-PTX cells compared with the parent cells. Expression of Bax and caspase-3 was significantly downregulated, whereas expression of Bcl-xL, P-glycoprotein, multidrug resistance-associated protein and VEGF was increased in rMKN45-PTX. The expression level of PKM1 was upregulated in rMKN45-PTX, leading to an increase in the PKM1/PKM2 ratio. Using xenograft models, we demonstrated that mouse subcutaneous tumors derived from rMKN45-PTX were significantly larger than those derived from MKN45 cells. CONCLUSION: Under the stress of chemotherapeutic agent exposure, high expression of HIF-1α affects various downstream genes. Although the underlying mechanism is unknown, our data suggest that PKM1 is also a molecular target for gastric cancer treatment.

Importance of human peritoneal mesothelial cells in the progression, fibrosis, and control of gastric cancer: inhibition of growth and fibrosis by tranilast.

BACKGROUND: Scirrhous gastric cancer is an intractable disease with a high incidence of peritoneal dissemination and obstructive symptoms (e.g., ileus, jaundice, and hydronephrosis) arising from accompanying marked fibrosis. Microenvironmental interactions between cancer cells and cancer-associated fibroblasts are the suggested cause of the disease. We elucidated the mechanisms of tumor growth and fibrosis using human peritoneal mesothelial cells (HPMCs) and investigated the effects of tranilast treatment on cells and a xenograft mouse model of fibrosis. METHODS: HPMCs were isolated from surgically excised omentum and their interaction with MKN-45 gastric cancer cells was investigated using co-culture. Furthermore, a fibrosis tumor model was developed based on subcutaneous transplantation of co-cultured cells into the dorsal side of nude mice to form large fibrotic tumors. Mice were subsequently treated with or without tranilast. RESULTS: The morphology of HPMCs treated with transforming growth factor (TGF)-ß1 changed from cobblestone to spindle-type. Moreover, E-cadherin was weakly expressed whereas high levels of α-smooth muscle actin expression were observed. TGF-ß-mediated epithelial-mesenchymal transition-like changes in HPMCs were inhibited in a dose-dependent manner following tranilast treatment through inhibition of Smad2 phosphorylation. In the mouse model, tumor size decreased significantly and fibrosis was inhibited in the tranilast treatment group compared with that in the control group. CONCLUSIONS: Tranilast acts on the TGF-ß/Smad pathway to inhibit interactions between cancer cells and cancer-associated fibroblasts, thereby inhibiting tumor growth and fibrosis. This study supports the hypothesis that tranilast represents a novel strategy to prevent fibrous tumor establishment represented by peritoneal dissemination.

Thoracoscopic Surgery in a Patient with Multiple Esophageal Carcinomas after Surgery for Esophageal Achalasia.

We present a case in which we used a thoracoscopic approach for resection of multiple esophageal carcinomas diagnosed 33 years after surgery for esophageal achalasia. A 68-year-old Japanese man had been diagnosed with esophageal achalasia and underwent surgical treatment 33 years earlier. He was examined at our hospital for annual routine checkup in which upper gastrointestinal endoscopy showed a "0-IIb+IIa" lesion in the middle esophagus. Iodine staining revealed multiple irregularly shaped iodine-unstained areas, the diagnosis of which was esophageal carcinoma. Thoracoscopic subtotal esophagectomy was performed. Esophageal carcinoma may occur many years after surgery for esophageal achalasia, even if the passage symptoms have improved. So, long-term periodic follow-up is necessary for detection of carcinoma at an earlier stage.

Sclerosing mesenteritis mimicking metachronous peritoneal metastases from descending colon adenocarcinoma.

BACKGROUND: Sclerosing mesenteritis is a non-neoplastic inflammatory disease that occurs in the bowel mesentery. Distinguishing sclerosing mesenteritis from neoplasms may be difficult because of the clinical and radiographic similarities between the two disease entities. CASE PRESENTATION: We report a case of sclerosing mesenteritis mimicking peritoneal metastases of colorectal carcinoma. A 73-year-old man with stage II descending colon adenocarcinoma with poor prognostic features was found to have developed left lower abdominal quadrant masses on computed tomography (CT) 9 months after undergoing radical surgery. These masses were diagnosed as peritoneal metastases because they grew in size and displayed fluorodeoxyglucose (FDG) uptake 3 months later; thus, a laparotomy was performed. The masses, which were localized in the jejunal mesentery, were excised completely via segmental jejunal resection. Histopathological analysis confirmed that the masses were sclerosing mesenteritis. The patient showed no signs of sclerosing mesenteritis or colorectal carcinoma recurrence during follow-up. CONCLUSIONS: In patients suspected of having localized peritoneal metastasis from malignancies, any masses must be sampled by surgical excisional biopsy and subsequently examined to rule out alternative diagnoses, such as sclerosing mesenteritis.

Potential of extravasated platelet aggregation as a surrogate marker for overall survival in patients with advanced gastric cancer treated with preoperative docetaxel, cisplatin and S-1: a retrospective observational study.

BACKGROUND: The theory of extravasated platelet aggregation in cancer lesions was recently introduced. We investigated the association of platelet aggregation in gastric cancer stroma with clinicopathological features, chemotherapeutic response, pathological response, and survival. METHODS: The study comprised 78 patients with advanced gastric cancer who had undergone gastrectomy with or without combination of docetaxel, cisplatin and S-1 (DCS) as preoperative chemotherapy between 2005 and 2014. The patients were divided into two groups: patients who had received preoperative DCS therapy forming the p-DCS group and patients who had not received preoperative DCS therapy forming the control group. The 39 patients in the control group had received gastrectomy and postoperative chemotherapy of S-1 alone. Platelet aggregation in biopsy specimens before preoperative DCS therapy in the p-DCS group and at the time of diagnosis in the control group were evaluated using CD42b immunohistochemical staining. RESULTS: Twenty-four patients in the p-DCS group and 19 in the control group were found to have platelet aggregation in their cancer stroma. Patients with histologically confirmed platelet aggregation had significantly higher rates of chemoresistance (58.3%) than those without platelet aggregation (20.0%) (P = 0.019). According to multivariate analysis, CD42b expression (odds ratio: 5.102, 95% confidence interval: 1.039-25.00, P = 0.045) was correlated with chemoresistance. CD42b expression and histological non-responder status were both significantly correlated with poor overall survival (OS) (P = 0.012, P = 0.016); however, RECIST was not correlated with OS. In the control group, CD42b expression was also significantly correlated with poor overall survival (OS) (P = 0.033). In the p-DCS group, according to multivariate analysis, male sex (hazard ratio: 0.281, 95% confidence interval: 0.093-0.846, P = 0.024) was correlated with good prognosis and CD42b expression (hazard ratio: 4.406, 95% confidence interval: 1.325-14.65, P = 0.016) with poor prognosis. CONCLUSIONS: This study suggests that platelets in gastric cancer stroma may create a favorable microenvironment for chemoresistance. CD42b immunohistochemical staining of biopsy specimens is a promising candidate for being a prognostic marker in patients with gastric cancer.

Low-dose paclitaxel suppresses the induction of M2 macrophages in gastric cancer.

Tumor-associated macrophages of the M2 phenotype promote tumor proliferation and are associated with a poor prognosis in patients with various malignancies, including gastric cancer with peritoneal dissemination. The present study assessed whether paclitaxel (PTX) suppresses M2 macrophages, by acting as a Toll-like receptor 4 (TLR4) agonist. Macrophages derived from the THP-1 monocytic cell line and peripheral blood mononuclear cell (PBMC)-derived macrophages were cultured with gastric cancer cells in medium containing PTX, at a concentration that did not affect cell proliferation. The effects of PTX on macrophage expression of CD204, a marker of M2 macrophages and NOS2, a marker of M1 macrophages, was evaluated by western blotting. The ability of PTX to stimulate intranuclear translocation of NF-κB was determined by evaluating the expression of the p65 subunit of NF-κB. In THP-1 macrophages, low-dose PTX (1 and 5 nM) inhibited the expression of CD204, enhanced the expression of NOS2, and significantly suppressed the phosphorylation of Stat3, which is essential for the M2 phenotype. Low-dose PTX also inhibited CD204 expression in primary macrophages derived from PBMCs. PTX treatment of THP-1 macrophages for 1 h induced marked intranuclear translocation of NF-κB p65. Low-dose PTX inhibited the M2 phenotype and induced the M1 phenotype via TLR4 signaling, suggesting that low-dose PTX can alter the macrophage phenotype, whereas clinical doses can kill cancer cells. These results suggest that the anticancer effects of PTX are due both to its cytotoxic and immunomodulatory activities.

Establishing a xenograft mouse model of peritoneal dissemination of gastric cancer with organ invasion and fibrosis.

BACKGROUND: The clinical prognosis of gastric cancer with peritoneal dissemination is poor because of its chemoresistance and rich fibrosis. While several gastric cancer cell lines have been used to establish models of peritoneal dissemination by intraperitoneal injection, most peritoneal tumors that form adopt a medullary pattern in microscopic appearance. This histological finding for the model differs from that in the clinical situation. This study was performed to demonstrate the contribution of human peritoneal mesothelial cells (HPMCs) to fibrotic tumor formation and to establish a new xenograft model with high potential for peritoneal dissemination with organ invasion and extensive fibrosis. METHODS: We established four types of xenograft model: i) intraperitoneal injection of MKN45-P cells alone (control group), ii) injection of MKN45-P cells co-cultured with HPMCs (co-cultured group), iii) scratching the parietal peritoneum (parietal group), and iv) scratching the visceral peritoneum (visceral group) with a cotton swab before injection of co-cultured cells. Fibrosis, α-smooth muscle actin expression, and organ invasion by tumor cells were all assessed by immunohistochemical examination. RESULTS: All mice developed abdominal swelling with peritoneal tumors and bloody ascites. Tumors of the control and co-cultured groups were not invasive or fibrotic. Contrastingly, tumors of the scratch groups exhibited rich stromal fibrosis and possessed increased α-smooth muscle actin (α-SMA) expression. In particular, the visceral group showed edematous and spreading tumors invading the intestinal wall. CONCLUSION: We established a model of peritoneal dissemination with organ invasion and stromal fibrosis. Formation of peritoneal dissemination required a favorable environment for cell adhesion, invasion, and growth. This model may be useful for analyzing the pathogenesis and treatment of peritoneal dissemination of gastric cancer.

[Laparoscopic Surgery for an Intussusception Caused by Rectosigmoid Colon Cancer after Pre-Operative Reduction by Transanal Insertion of a Circular Sizer - A Case Report].

An octogenarian man complaining of bloody stool was referred to our hospital. A digital examination, abdominal enhanced CT and endoscopy led to a diagnosis of intussusception due to rectosigmoid colon cancer, but he was not suffering from bowel obstruction. An elective laparoscopic Hartmann's operation was performed after reduction by transanal insertion of a circular sizer. It may be difficult to reduce an intussusception induced by rectal cancer. We report this case with a review of the relevant literature.