Feasibility of laparoscopic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumor with tumor diameter of >5 cm.

BACKGROUND: Laparoscopic and endoscopic cooperative surgery (LECS) is an effective treatment for gastric gastrointestinal stromal tumors (GISTs). The utility of LECS for gastric GISTs of > 5 cm remains controversial. This study was performed to investigate the feasibility of LECS for gastric GISTs with a tumor diameter of >5 cm. METHODS: We analyzed 43 patients with gastric GISTs who underwent LECS or laparoscopic partial gastrectomy (Lap-Partial Gx). We compared the surgical outcomes of LECS versus Lap-Partial Gx and of LECS for a tumor diameter of > 5 versus ≤ 5 cm. RESULTS: In the comparison of LECS versus Lap-Partial Gx, there were no significant intergroup differences in the operative time or blood loss volume. The morbidity rate was similar between the groups. No postoperative mortality occurred in either group. In the comparison of LECS for a tumor diameter of > 5 versus ≤ 5 cm, there were no significant intergroup differences in operative time, or blood loss volume. The morbidity rate was similar between the > 5-cm and ≤ 5-cm groups (0.0% vs. 4.5%, respectively ; p = 0.56). Additionally, no recurrence or death occurred during follow-up in either group. CONCLUSION: LECS is a feasible option for gastric GISTs with a tumor diameter of > 5 cm. J. Med. Invest. 71 : 148-153, February, 2024.

Number of Healthy Teeth Can Predict the Response of Rectal Cancer to Chemoradiotherapy: A Retrospective Study.

BACKGROUND: It has been reported that the oral and gut microbiomes are associated with the prognosis in patients who undergo surgery, chemotherapy, and radiation for colorectal cancer. This study is the first to identify a correlation between the number of healthy teeth, which is an oral health indicator, and the efficacy of preoperative chemotherapy for rectal cancer. METHODS: This retrospective single-center study included 30 patients who underwent radical surgery after preoperative chemoradiotherapy (CRT) between December 2013 and June 2021. The relationship between number of teeth before CRT and the efficacy of CRT, CRT-related adverse events, postoperative complications, and long-term postoperative outcomes was examined. RESULTS: The number of healthy teeth was significantly greater in patients with downstaging of their disease than in those without downstaging (P = .027) and in patients with a complete response according to the Response Evaluation Criteria in Solid Tumors than in those who did not have a complete response (P = .014). Patients were divided into two groups according to whether they had ≥15 teeth or ≤14 teeth. There was no significant between-group difference in CRT-related adverse events. The incidence of all postoperative complications and grade II postoperative complications tended to be higher in patients with ≥15 teeth (P = .071 and P = .092, respectively), as did the 5-year overall survival rate (P = .083) and the 5-year disease-free rate (P = .007). DISCUSSION: The number of healthy teeth predicted the response to preoperative CRT, postoperative complications, and the outcome of subsequent surgery in patients with rectal cancer.

Comparison of the short-term surgical outcomes of lateral lymph node dissection for low rectal cancer using a robotic-assisted transabdominal approach alone or supported by a transanal approach.

BACKGROUND: Lateral lymph node metastases are a major cause of local recurrence after surgery for advanced low rectal cancer. Lateral lymph node dissection (LLND) may reduce the risk of local recurrence in patients with suspected lateral lymph node metastasis. Recent reports have shown that robotic-assisted LLND can help to reduce the postoperative complication rate, such as urinary disturbance. Furthermore, with the advent of transanal total mesorectal excision, a novel LLND procedure that combines a transabdominal approach with a transanal approach has been reported. This study aimed to clarify the safety and feasibility of robotic-assisted LLND supported by a transanal approach for advanced low rectal cancer. METHODS: Thirty-nine patients diagnosed to have low rectal cancer between June 2019 and May 2023 were retrospectively enrolled and divided according to whether they underwent LLND via a robotic-assisted transabdominal approach alone (transabdominal group, n = 19) or in combination with a transanal approach (2team group, n = 20). The patient characteristics and short-term surgical outcomes were compared between the two groups. RESULTS: The total operation time was significantly shorter in the 2team group than in the transabdominal group (366 min vs. 513 min, P < 0.001), as was the time taken to perform unilateral LLND (64 min vs. 114 min, P < 0.001). Furthermore, there was significantly less intraoperative bleeding in the 2team group (30 mL vs. 80 mL, P = 0.004). There was no significant between-group difference in postoperative complications. The incidence of postoperative urinary disturbance was satisfactory at 5% in both groups. CONCLUSIONS: The operation time for LLND performed by a robotic-assisted transabdominal approach was shortened when supported by a transanal approach. The frequency of postoperative urinary disturbance was low in both groups. Therefore, robotic-assisted abdominal LLND supported by a transanal approach can be considered a promising treatment option for advanced low rectal cancer.

Preoperative evaluation to determine the difficulty of No. 6 lymphadenectomy in laparoscopic gastrectomy.

BACKGROUND: Laparoscopic gastrectomy (LG) requires a long learning curve because of the complicated surgical procedures. Infrapyloric (No. 6) lymph node dissection (LND) is one of the difficult procedures in LG, especially for trainees. This study investigated the impact of the prediction of the difficulty of No. 6 LND. METHODS: We retrospectively reviewed the preoperative computed tomography (CT) images and individual operative video records of 57 patients who underwent LG with No. 6 LND to define and predict the No. 6 LND difficulty. To evaluate whether prediction of the difficulty of No. 6 LND could improve surgical outcomes, 48 patients who underwent laparoscopic distal gastrectomy were assessed (30 patients without prediction by a qualified surgeon and 18 patients with prediction by a trainee). RESULTS: The anatomical characteristic that LND required > 2 cm of dissection along the right gastroepiploic vein was defined as difficulty of No. 6 LND. Of the 57 LG patients, difficulty was identified intraoperatively in 21 patients (36.8%). Among the several evaluated anatomical parameters, the length between the right gastroepiploic vein and the right gastroepiploic artery in the maximum intensity projection in contrast-enhanced CT images was significantly correlated with the intraoperative difficulty of No. 6 LND (p < 0.0001). Surgical outcomes, namely intraoperative minor bleeding, postoperative pancreatic fistula, and drain amylase concentration were not significantly different between LG performed by a trainee with prediction compared with that by a specialist without prediction. CONCLUSIONS: Preoperative evaluation of the difficulty of No. 6 LND is useful for trainees, to improve surgical outcomes.

Role of stromal PD-L1 expression in colorectal liver metastasis.

BACKGROUND AND AIM: The outcomes of immune checkpoint blockade for colorectal cancer (CRC) treatment are unsatisfactory. Furthermore, the efficacy of immune checkpoint blockade for liver metastasis of various cancer is poor. Here, we investigated the relationship between stromal programmed death-ligand 1 (PD-L1) expression and the prognosis of patients with colorectal cancer liver metastasis (CRLM). METHODS: The present study enrolled 84 CRLM patients who underwent surgery (R0) for CRC. Immunohistochemistry was performed to analyze stromal PD-L1 expression in CRLM. RESULTS: Stromal PD-L1 was expressed in 52.3% of CRLM samples, which was associated with fewer not optimally resectable metastases (p = 0.04). Stromal PD-L1 also tended to associate with a lower tumor grade (p = 0.08). Stromal PD-L1-positive patients had longer overall survival (p = 0.003). Multivariate analysis identified stromal PD-L1 expression (p = 0.008) and poorer differentiation (p < 0.001) as independent prognostic indicators. Furthermore, stromal PD-L1 expression was correlated to a high number of tumor-infiltrating lymphocytes (TILs). Stromal PD-L1- and low TIL groups had shorter OS than stromal PD-L1 + and high TIL groups (46.6% vs. 81.8%, p = 0.05) Stromal PD-L1-positive patients had longer disease-free survival (DFS) (p = 0.03) and time to surgical failure (p = 0.001). Interestingly, stromal PD-L1 expression was positively related to the desmoplastic subtype (p = 0.0002) and inversely related to the replacement subtype of the histological growth pattern (p = 0.008). CONCLUSIONS: Stromal PD-L1 expression may be a significant prognostic marker for CRLM.

Conversion surgery after successful response to chemotherapy (S-1 + oxaliplatin + nivolumab) in a patient with stage IV gastric cancer with peritoneal metastasis (P1, CY1): a case report.

We here present a case report of a patient with Stage IV gastric cancer with peritoneal metastasis (P1, CY1) who underwent conversion surgery after a successful response to chemotherapy (S-1 + oxaliplatin + nivolumab). The patient was a woman in her 60 s. Her chief complaint was epigastric pain. Upper gastrointestinal endoscopy showed Type 4 advanced carcinoma on the lesser curvature of the gastric body. Biopsy showed Group 5 (poorly differentiated adenocarcinoma) and HER2 was negative. Staging laparoscopy revealed seeding in the round ligament of the liver (P1) and adenocarcinoma cells in ascites (CY1). Ten courses of chemotherapy (S-1 + oxaliplatin + nivolumab) were administered, after which contrast-enhanced computed tomography showed that the primary tumor had shrunk and seeding was no longer detectable. Upper gastrointestinal endoscopy revealed scar-like changes. A second staging laparoscopy revealed that ascites cytology was negative and a biopsy of the round ligament of the liver showed no malignant cells (P0, CY0). Conversion surgery comprising laparoscopic total gastrectomy with D2 lymph node dissection and resection of the round ligament of the liver was performed. The postoperative course was uneventful. Histopathological examination of the resected specimen revealed no tumor cells in the gastric mesentery or the round ligament of the liver. The pathological diagnosis was gastric cancer [M, U, L, Less, Ant, Post, type4, T3(SS), N0, M0 (H0, P0, CY0), ypStage IIA]. Adjuvant chemotherapy (S-1) was commenced. The patient is still alive 7 months later with no evidence of recurrence.

Role of Nrf2 signaling in development of hepatocyte-like cells.

Generation of hepatocytes from human adipose-derived mesenchymal stem cells (hADSCs) could be a promising alternative source of human hepatocytes. However, mechanisms to differentiate hepatocytes from hADSCs are not fully elucidated. We have previously demonstrated that our three-step differentiation protocol with glycogen synthase kinase (GSK) 3 inhibitor was effective to improve hepatocyte functions. In this study, we investigated the activation of the nuclear factor erythroid-2 related factor 2 (Nrf2) on hADSCs undergoing differentiation to HLC (hepatocyte-like cells). Our three-step differentiation protocol was applied for 21 days (Step 1:day 1-6, Step2:day 6-11, Step3:day 11-21). Our results show that significant nuclear translocation of Nrf2 occurred from day 11 until the end of HLC differentiation. Nuclear translocation of Nrf2 and CYP3A4 activity in the GSK3 inhibitor-treated group was obviously higher than that in Activin A-treated groups at day 11. The maturation of HLCs was delayed in Nrf2-siRNA group compared to control group. Furthermore, CYP3A4 activity in Nrf2-siRNA group was decreased at the almost same level in Activin A-treated group. Nrf2 translocation might enhance the function of HLC and be a target for developing highly functional HLC. J. Med. Invest. 70 : 343-349, August, 2023.

Prognostic impact of frailty after gastrectomy in elderly gastric cancer patients.

BACKGROUND: Frailty plays a crucial role in cancer patients who have received surgery in this recent aging society. We aimed to investigate frailty as a prognostic factor in elderly gastric cancer (GC) patients who underwent curative gastrectomy. METHODS: We analyzed 86 elderly (over 75 years old) GC patients who underwent curative gastrectomy. Patients were assigned to two groups;frailty group (n=29) and no-frailty group (n=57). Clinicopathological values were compared between the two groups. RESULTS: The OS rate of the frailty group was significantly poorer than that of the no-frailty group (5-yr OS rate;frailty group 52.49% vs. no-frailty group 74.87%, p<0.05). Multivariate analysis of the OS showed that frailty tended to be significant prognostic factor (p=0.09). The DFS rate of the frailty group was significantly poorer than that of the no-frailty group (5-yr DFS rate;frailty group 42.30% vs. no-frailty group 71.55%, p<0.05). Multivariate analysis of the DFS showed that frailty tended to be significant prognostic factor (p=0.14). CONCLUSION: We identified the clinical impact of frailty prognostic factor for elderly GC patients who underwent gastrectomy. J. Med. Invest. 70 : 423-429, August, 2023.

Association between high expression of intratumoral fibroblast activation protein and survival in patients with intrahepatic cholangiocarcinoma.

BACKGROUND: Cancer-associated fibroblasts (CAFs) have been reported to exhibit protumorigenic effects. Among the well-known CAF markers such as smooth muscle actin (SMA) and fibroblast activation protein (FAP), high expression of SMA in the peritumoral stroma has been reported to be a prognostic factor in various cancers. However, the effect of high FAP expression in intrahepatic cholangiocarcinoma (IHCC) has not been fully clarified. We evaluated the expression of CAF markers, focusing on FAP expression in the peripheral and intratumoral regions, to clarify the association with survival in patients with IHCC. METHODS: The study cohort comprised 37 patients who underwent curative resection for IHCC. The FAP expressions were evaluated in the peripheral and intratumoral regions of the resected tissues. Clinicopathological factors and survival outcomes were investigated between patients with high versus low FAP expression. Uni- and multivariate analyses were performed to identify the prognostic factors for overall survival and relapse-free survival. RESULTS: The median area percentages of FAP expression in the peripheral and intratumoral regions were 15.5% and 17.8%, respectively. High FAP expression in the intratumoral region was significantly associated with worse overall survival and disease-free survival than low FAP expression in the intratumoral region. Multivariate analysis identified high intratumoral FAP expression as a risk factor for worse overall survival (hazard ratio, 2.450; p = 0.049) and relapse-free survival (hazard ratio, 2.743; p = 0.034). CONCLUSIONS: High intratumoral FAP expression was associated with worse survival, suggesting that intratumoral FAP expression represents malignant progression in patients with IHCC.

The Impact of the Pre-operative Neutrophil-lymphocyte Ratio as the Predictive Marker of Post-operative Weight Loss and Improving Diabetes in Sleeve Gastrectomy.

PURPOSE: The aim was to investigate the impact of the neutrophil-lymphocyte ratio (NLR) in sleeve gastrectomy (SG). METHODS: 15 obese patients were enrolled in this study ; mean body weight (BW) 127.5kg ; mean body mass index (BMI) 46.7kg/m2. 10 of these were diabetics who underwent a SG. The impact of the pre-operative NLR on the percentage of excess weight loss (%EWL) and remission of diabetes 1 year post-operative were examined. RESULTS: The %EWL at 1 year post-operative were 46.3%. Improvements were also evident in the diabetes at 1 year post-operative : complete remission (CR) 40%, partial remission (PR) 20% and Improve 40%. Comparing pre-operative NLR in %EWL<50% and ≧50% in 1 year post-operative, <50% was 2.64 and ≧50% was 2.03. The NLR in CR and PR was significantly lower than that in Improve. CONCLUSIONS: The pre-operative NLR may be a predictive marker of weight loss and improving diabetes after SG. J. Med. Invest. 70 : 140-144, February, 2023.

Impact of L-type amino acid transporter 1 on intrahepatic cholangiocarcinoma.

BACKGROUND: Amino acid transporters, such as L-type amino acid transporter 1 (LAT1), have an effect on tumor growth, metastasis, and survival of various solid tumors. However, the role of LAT1 in patients with intrahepatic cholangiocarcinoma (IHCC) remains unknown. METHODS: Forty-six patients who had undergone initial hepatic resection for IHCC at Tokushima University Hospital were enrolled in this study. Immunohistochemical analysis of LAT1 and phosphorylated Akt (p-AKT) was performed using resected specimens. Clinicopathological factors, including prognosis, were analyzed between LAT1-high and LAT1-low groups. RESULTS: The LAT1-high group showed a higher proportion of periductal infiltrating type and higher carcinoembryonic antigen/carbohydrate antigen 19-9 levels compared with the LAT1-low group. Multivariate analysis revealed that LAT1-high expression was an independent prognostic factor for disease-free survival. Furthermore, the proportion of p-AKT positivity was higher in the LAT1-high group than in the LAT1-low group. CONCLUSIONS: LAT1 expression was associated with poor prognosis of IHCC and higher p-Akt expression. J. Med. Invest. 70 : 160-165, February, 2023.

Utility of robotic surgery for Siewert type II/III adenocarcinoma of esophagogastric junction: transhiatal robotic versus laparoscopic approach.

BACKGROUND: Robotic surgery (RS) has been rapidly adopted for gastric cancer and adenocarcinoma of the esophagogastric junction (AEG). However, the utility of RS for Siewert type II/III AEG remains unclear. METHODS: Forty-one patients who underwent either transhiatal RS (n = 15) or laparoscopic surgery (LS) (n = 26) for Siewert type II/III AEG were enrolled in this study. The surgical outcomes of the two groups were compared. RESULTS: In the entire cohort, there were no significant intergroup differences in the operative time, blood loss volume, or number of retrieved lymph nodes. The length of the postoperative hospital stay was shorter in the RS group than in the LS group (14.20 ± 7.10 days vs. 18.73 ± 17.82 days, respectively; p = 0.0388). The morbidity rate (Clavien-Dindo grade ≥ 2) was similar between the groups. In the Siewert II cohort, there were no significant intergroup differences in short-term outcomes. In the entire cohort, there was no significant difference between the RS and LS groups in the 3-year overall survival rate (91.67% vs. 91.48%, N.S.) or 3-year disease-free survival rate (91.67% vs. 91.78%, N.S.), respectively. Likewise, in the Siewert type II cohort, there was no significant difference between the RS and LS groups in the 3-year overall survival rate (80.00% vs. 93.33%, N.S.) or 3-year disease-free survival rate (80.00% vs. 94.12%, N.S.), respectively. CONCLUSIONS: Transhiatal RS for Siewert II/III AEG was safe and contributed to similar short-term and long-term outcomes compared with LS.

The application of enhanced recovery after surgery in total gastrectomy: a propensity score-matched analysis.

BACKGROUND: This study aimed to investigate the feasibility and safety of our enhanced recovery after surgery protocol including early oral intake and omitting nasogastric tube (NGT) placement after total gastrectomy. METHODS: We analyzed 182 consecutive patients who underwent total gastrectomy. The clinical pathway was changed in 2015, and patients were divided into 2 groups (conventional group and modified group). Postoperative complications, bowel movement, and postoperative hospital stays were compared in the two groups in all cases and propensity score matching (PSM). RESULTS: Flatus and defecation were significantly earlier in the modified group compared with those in the conventional group (flatus: 2 (1-5) days vs 3 (2-12) days, p = 0.03; defecation: 4 (1-14) days vs 6 (2-12) days p = 0.04). The postoperative hospital stay was 18 (6-90) days in the conventional group and 14 (7-74) days in the modified group (p = 0.009). Days until discharge criteria were met were earlier in the modified group compared with that in the conventional group (10 (7-69) days vs 14 (6-84) days p = 0.01). Overall and severe complications occurred in nine patients (12.6%) and three patients (4.2%) in the conventional group and twelve patients (10.8%) and four patients (3.6%) in the modified group, respectively (p = 0.70 and p = 0.83) in all cases. In PSM, there is no significant difference between the two groups concerning the postoperative complications (overall complication 6 (12.5%) vs 8 (16.7%) p = 0.56, severe complications 1 (2%) vs 2 (4.2%) p = 0.83). CONCLUSIONS: Modified ERAS for total gastrectomy may be feasible and safe.

Transanal lateral lymph node dissection with intraoperative hologram support in low rectal cancer.

BACKGROUND: In Japan, the standard treatment for stage II/III advanced low rectal cancer is total mesorectal excision plus lateral lymph node dissection (LLND). There are also recent reports on the use of transanal LLND. However, the transanal anatomy is difficult to understand, and additional support tools are required to improve the surgical safety. The present study examined the utility of holograms with mixed reality as an intraoperative support tool for assessing the complex pelvic anatomy. METHODS: Polygon (stereolithography) files of patients' pelvic organs were created and exported from the SYNAPSE VINCENT imaging system and uploaded into the Holoeyes MD virtual reality software. Three-dimensional images were automatically converted into patient-specific holograms. Each hologram was then installed into a head mount display (HoloLens2), and the surgeons and assistants wore the HoloLens2 when they performed transanal LLND. Twelve digestive surgeons with prior practice in hologram manipulation evaluated the utility of the intraoperative hologram support by means of a questionnaire. RESULTS: Intraoperative hologram support improved the surgical understanding of the lateral lymph node region anatomy. In the questionnaire, 75% of the surgeons answered that the hologram accurately reflected the anatomy, and 92% of the surgeons answered that the anatomy was better understood by simulating the hologram intraoperatively than preoperatively. Moreover, 92% of the surgeons agreed that intraoperative holograms were a useful support tool for improving the surgical safety. CONCLUSIONS: Intraoperative hologram support improved the surgical understanding of the pelvic anatomy for transanal LLND. Intraoperative holograms may represent a next-generation surgical tool for transanal LLND.

Stapler insertion angle toward the esophagus reduces the incidence of early postoperative Roux stasis syndrome after distal gastrectomy in minimally invasive surgery.

BACKGROUND: Roux stasis syndrome (RSS) after Roux-en-Y (RY) reconstruction significantly prolongs the hospital stay and decreases the quality of life. The purpose of the present study was to evaluate the incidence of RSS in patients who underwent distal gastrectomy for gastric cancer and to identify the factors related to the development of RSS after mechanical RY reconstruction in minimally invasive surgery (MIS). METHODS: This study included 134 patients who underwent distal gastrectomy in MIS with mechanical RY anastomosis. RSS was defined as the presence of symptoms such as nausea, vomiting, or abdominal fullness, and the confirmation of delayed gastric emptying on imaging or gastrointestinal fiber testing. Clinical data were checked, including body mass index, operative procedure, age, sex, operative time, blood loss volume, extent of lymph node dissection, final stage, stapler insertion angle, method of entry hole closure. The relationship between the incidence of RSS and these factors was analyzed. RESULTS: RSS occurred in 24 of 134 patients (17.9%). RSS occurred significantly more frequently in patients with D2 lymphadenectomy than in patients with D1 + lymphadenectomy (p = 0.04). All patients underwent side-to-side anastomosis via the antecolic route. The incidence of RSS was significantly greater in patients with a stapler insertion angle toward the greater curvature (n = 20, 22.5%) versus the esophagus (n = 4, 8.9%) (p = 0.04). The multivariate logistic regression model revealed that the stapler insertion angle to the greater curvature is identified as independent risk factor for RSS (OR 3.23, 95%Cl 1.01-10.3, p = 0.04). CONCLUSION: Stapler insertion angle toward the esophagus may reduce the incidence of early postoperative RSS rather than toward the greater curvature.

Effect of duodenal-jejunal bypass on diabetes in the early postoperative period.

Metabolic surgery is an effective treatment for patients with type 2 diabetes mellitus (T2DM). The aim of this study was to investigate the effect of duodenal-jejunal bypass (DJB) in a rat model of T2DM during the early postoperative period. A rat model of non-obese T2DM was allocated to two groups: a sham group and a DJB group. On postoperative day 1 (1POD), oral glucose tolerance testing (OGTT) was performed and the changes of glucose transporter expressions in the small intestine was evaluated. [18F]-fluorodeoxyglucose ([18]-FDG) uptake was measured in sham- and DJB-operated rats using positron emission tomography-computed tomography (PET-CT). DJB improved the glucose tolerance of the rats on 1POD. The expression of sodium-glucose cotransporter 1 (SGLT1) and glucose transporter 1 (GLUT1) was high, and that of GLUT2 was low in the alimentary limb (AL) of rats in the DJB group. PET-CT showed that [18F]-FDG uptake was high in the proximal jejunum of DJB-operated rats. These results may show that DJB improve glucose tolerance in very early postoperative period as the result of glucose accumulation in the AL because of changes in glucose transporter expression.

Visualization of the pelvic nerves using magnetic resonance imaging for rectal cancer surgery.

BACKGROUND: This study evaluated the visualization of the pelvic nerves using magnetic resonance imaging (MRI) combined with computed tomography (CT) to synthesize three-dimensional (3D) reconstruction images of the pelvic organs. METHODS: The CT and MRI scans were performed for patients with rectal cancer who underwent surgery. The out-of-phase image of LAVA-Flex was used to identify the pelvic nerves. The images of the pelvic nerves were extracted from the MRI scans, and those of the arteries and rectum and pelvis were extracted from the CT scans. Each extracted organ image was used to synthesize 3D reconstruction images. RESULTS: The MRI scan allowed adequate visualization of the pelvic splanchnic nerves, inferior hypogastric plexus, and obturator nerves. The comparison of 3D reconstruction images and intraoperative findings showed matched images. CONCLUSION: We visualized the pelvic nerves using MRI and synthesized 3D reconstruction images of the pelvic organs. Preoperative confirmation of the location of the pelvic organs is important to prevent unanticipated injury during rectal cancer surgery.

Pleomorphic type undifferentiated gastric sarcoma, report of a case.

Reports on pleomorphic type of undifferentiated sarcoma (PUS) originating from the gastrointestinal tract, especially the stomach, are extremely rare. We herein report a case of pleomorphic type undifferentiated gastric sarcoma. The patient was a 67-year-old woman. The chief complaint was upper abdominal pain. Upper gastrointestinal endoscopy, ultrasonography, and contrast-enhanced computed tomography showed two submucosal tumors at the greater curvature of the fundus and the lesser curvature of the gastric angle. Endoscopic ultrasound-guided fine-needle aspiration revealed a c-kit-negative spindle cell tumor at the greater curvature of the fundus. Total gastrectomy, splenectomy, and partial resection of the diaphragm and liver were performed. One lesion had invaded the lateral segment of the liver, left diaphragm and spleen. The postoperative course was uneventful. Histopathological and immunohistochemical examinations of the resected specimen revealed PUS. Peritoneal dissemination was detected at 8 months after surgery. However, no effective therapeutic agents were adopted for chemotherapy. The patient had poor performance status due to disease progression and underwent best supportive care. The patient died 10 months after surgery. This case highlights the imaging, histological diagnosis, and treatment strategy for PUS originating from the stomach. Surgeons should be aware of PUS as a differential diagnosis in cases with submucosal tumor of the stomach.

Characteristic submucosal alteration in biliary carcinogenesis of pancreaticobiliary maljunction with a focus on inflammasome activation.

BACKGROUND: This study investigated submucosal alterations in biliary carcinogenesis of pancreaticobiliary maljunction (PBM). METHODS: Thirty-three patients with PBM (including seven with gallbladder [GB] cancer), four with neither biliary tract cancer nor PBM who underwent pancreaticoduodenectomy (controls), and seven with chronic cholecystitis without PBM were enrolled. Protein expression of α-smooth muscle actin (αSMA), CD68, and CD204 in the GB lamina propria and that of NLRP3 and caspase 1 in the GB epithelium and lamina propria were examined. RESULTS: Compared with the control and cholecystitis groups, αSMA expression was higher in the cancerous part (stroma) of the GB in patients with GB cancer + PBM and in the lamina propria of patients with PBM. The CD204/CD68 ratio in the lamina propria was higher in the PBM group than in the control and cholecystitis groups. NLRP3 and caspase 1 expression in both the lamina propria and epithelium was higher in the PBM than control group. In the PBM group, NLRP3- and caspase 1-positive cells in the lamina propria were located near the epithelium. CONCLUSION: Activated fibroblasts and M2 macrophages in the GB lamina propria may be associated with biliary carcinogenesis of PBM, possibly through inflammasome activation.