CD44-positive Cancer Stem-like Cells as a Potential Source of Peritoneal Metastasis After Surgery.

BACKGROUND/AIM: The role of CD44 in gastric cancer-derived peritoneal metastasis is currently unknown. It was previously shown that viable, tumorigenic cancer cells are spilled into the peritoneal cavity during surgery, providing a potential cause of peritoneal recurrence after surgery. The purpose of this study was to elucidate the mechanism of peritoneal metastasis of gastric cancer through the expression of CD44 and to propose a method for preventing peritoneal recurrence. MATERIALS AND METHODS: Gastric cancer cell line MKN-45 was sorted into CD44+ and CD44- cells and then injected intraperitoneally into NOD/ShiJic-scidJcl mice. Differences in tumor-initiating capacity between the two groups were assessed using in vivo limiting dilution assays. Tumors harvested from both groups were examined for CD44 and ALDH1A1 expression using immunohistochemistry. The effects of CD44 blockade with anti-CD44 antibody on cell invasion and peritoneal metastasis formation in vivo were assessed. RESULTS: CD44+ cells showed significantly higher efficiency in initiating peritoneal tumor than CD44- cells. Blockade of CD44 significantly reduced peritoneal dissemination of CD44+ cells in vivo, indicating that the CD44 function of intraperitoneally disseminated cancer cells helped promote the formation of peritoneal metastasis. The margin of established tumors showed clusters of cells co-expressing CD44 and ALDH1A1. Peritoneally administered CD44- cells resulted in peritoneal metastases consisting of CD44+ and CD44- cancer cells. CONCLUSION: CD44 expressing cells are a potential source of peritoneal metastasis after surgery and could be a promising target for preventing peritoneal recurrence.

Preoperative Physical Activity Level Measurement by Accelerometer for Predicting Post-Hepatectomy Complications: A Prospective Observational Study.

INTRODUCTION: Recently, accelerometers have received much attention around the world. This study examined whether the preoperative physical activity level measured by an accelerometer could be a useful predictor of post-hepatectomy complications. METHODS: Between December 2016 and December 2020, the physical activity levels of 185 patients were measured using an accelerometer 3 days before hepatectomy and from postoperative day 1 to 7. The patients without postoperative complications (n = 153) and those with postoperative complications (n = 32) were compared using either the χ2 test or Fisher's exact test for nominal variables; continuous variables were analyzed using either Student's t test or Mann-Whitney U test. Differences were considered statistically significant when the p value was <0.05. Risk factors for postoperative complications following hepatectomy were also investigated. RESULTS: The number of patients with an anatomical resection was significantly higher in patients with postoperative complications (p = 0.001). Furthermore, laparoscopic hepatectomy was performed in 65.4% of patients without postoperative complications and in 25.0% of those with postoperative complications; the difference was statistically significant (p < 0.001). The average preoperative physical activity level was 150.6 kcal/day in patients without postoperative complications and 84.5 kcal/day in those with postoperative complications (p = 0.001). Multivariate analysis identified blood loss, operative time, and preoperative physical activity level as independent risk factors for postoperative complications. DISCUSSION/CONCLUSION: Patients with lower preoperative physical activity levels are at a high risk of developing postoperative complications after hepatectomy. Hence, preoperative physical activity level measurement may be useful in predicting post-hepatectomy complications.

Adverse impact of postoperative intra-abdominal infectious complications on cancer recurrence-related survival after curative gastric cancer surgery.

BACKGROUND: This study aimed to evaluate the impact of postoperative intra-abdominal infectious complications (PICs) on survival after surgery for gastric cancer. METHODS: A total of 152 patients who underwent curative gastrectomy for gastric cancer were included. The effect of clinicopathological features and PICs on recurrence-free survival (RFS) and overall survival (OS) were investigated. RESULTS: The median age was 67 years. The pathological stage was stage I (61), II (40), and III (51). Thirty-two patients (21.1%) had PICs: 9, pancreatic fistula; 14, anastomotic leakage; and 17, intra-abdominal abscess. The five-year RFS and OS rates were significantly lower in patients with PICs than in those without PICs (63.4 vs. 85.6%; p < 0.01 and 56.4 vs. 80.3%; p < 0.01, respectively). In multivariate analysis, intraoperative blood loss was an independent prognostic factor for PICs. CONCLUSIONS: Patients with PICs had worse clinical outcomes. Reducing intraoperative bleeding may improve the prognosis of gastric cancer.

Predictors and clinical impact of postoperative diarrhea after colorectal cancer surgery: a prospective, multicenter, observational study (SHISA-1602).

PURPOSE: Postoperative diarrhea, including high-output stoma (HOS), frequently occurs after colorectal surgery; its risk factors and clinical implications on subsequent complications remain unknown. This study aimed to evaluate the risk factors and clinical implications of postoperative diarrhea after primary colorectal cancer (CRC) surgery. METHODS: This prospective observational study included patients with CRC who underwent radical surgery at six hospitals between June 2016 and December 2017. The patients were categorized into three groups (non-stoma, colostoma, and ileostoma groups). RESULTS: A total of 178 patients participated in the study. In the non-stoma group, the incidence of postoperative diarrhea was 18.4% (27/147). The incidence of HOS was 28.6% (4/14) in the ileostoma group, and 0% in the colostoma group. Multivariable analyses of the incidence of diarrhea in the non-stoma group indicated that habitual smoking and hypertension were significantly associated with postoperative diarrhea (P = 0.012 and P = 0.0274, respectively). Postoperative diarrhea was more likely to occur in patients with rectal cancer than in those with colon cancer (P = 0.0501). In the non-stoma and ileostoma groups, the probability of the occurrence of other complications with Clavien-Dindo (C-D) grades II or higher was significantly higher in patients with C-D grade I diarrhea, including HOS, than in patients without diarrhea (39.3% vs. 14.6%, P = 0.0061). CONCLUSIONS: Smoking and hypertension are the independent predictors of postoperative diarrhea after an elective CRC surgery. Rectal cancer surgery seems to be associated with postoperative diarrhea more than colon cancer surgery does. Mild postoperative diarrhea may lead to more severe complications.

Incidence of surgical site infections with triclosan-coated monofilament versus multifilament sutures in elective colorectal surgery.

PURPOSE: Surgical site infections (SSIs) are the most frequent complication of abdominal surgery. Using triclosan-coated sutures for abdominal wall closure reportedly reduces the incidence of SSIs. However, the SSI incidence has not been compared between the use of triclosan-coated multifilament and triclosan-coated monofilament sutures. We, therefore, compared the incidence of incisional SSIs between the use of triclosan-coated polyglactin 910 sutures (Vicryl Plus) and triclosan-coated polydioxanone sutures (PDS Plus). METHODS: This observational cohort study was conducted on 318 consecutive patients who underwent elective colorectal cancer surgery at the Shiga University of Medical Science Hospital from January 2015 to December 2018. Based on the suture type for abdominal wall closure, 151 patients were enrolled in the PDS Plus group, and 167 were enrolled in the Vicryl Plus group. RESULTS: The two suture groups were not significantly different in terms of risk factors for SSIs. Other postoperative complications also did not differ markedly between the two groups. In the multivariate logistic regression analysis, the presence of stoma was the only independent risk factor for incisional SSIs. CONCLUSION: The incidence of incisional SSIs was unaffected by the type of triclosan-coated sutures. The presence of stoma was an independent risk factor for incisional SSIs.

Usefulness of measuring temporal changes in physical activity levels using an accelerometer for prediction and early detection of postoperative complications after hepatectomy.

BACKGROUND: This research aimed to determine whether patterns of temporal changes in activity levels can indicate postoperative complications following hepatectomy. METHODS: Between December 2016 and December 2019, 147 patients wore an accelerometer to measure their physical activity levels after hepatectomy until postoperative day 7. Patterns of changes in activity levels were categorized as follows: upward slope type (n = 88), wherein activity levels gradually increased; bell curve type (n = 13), wherein activity levels initially increased but subsequently decreased; and flat type (n = 46), wherein there was no apparent increase in activity levels. Patient characteristics and postoperative complications were compared for each group. RESULTS: Postoperative complications occurred in 4.5% of patients in the upward slope group, in 76.9% in the bell curve group, and in 65.2% in the flat group (p < 0.001). Surgical site infections (SSI), refractory pleural effusion, and ascites were more common in the bell curve group, while pneumonia was only observed in the flat group. CONCLUSION: SSI, pleural effusion, and ascites should be considered when previously increasing activity levels decline during the postoperative period. In addition, there is a high risk of SSI and pneumonia when activity levels do not increase at all after surgery.

Long-term prognosis of patients with cancer-related genes detected in postoperative peritoneal washings obtained during curative gastrectomy.

BACKGROUND: Cancer cells in intraoperative peritoneal washings (PW) indicate increased peritoneal recurrence. Detection of CEA or CK20 genes indicates poor prognosis. We assessed long-term prognosis of patients with amplification of cancer-related genes in PW obtained intraoperatively during curative gastric cancer surgery. METHODS: PW was collected before and immediately after curative gastrectomy. CEA, CK20, TFF1, MUC2, and FABP1-mRNA were selected as marker genes for reverse transcription polymerase chain reaction. Peritoneal recurrence-free survival (PRFS) and overall survival (OS) after >7-year follow-up were examined using the Kaplan-Meier method. RESULTS: Of 138 patients who underwent gastrectomy with negative cytological findings at laparotomy, 80 patients showed negative cancer-related gene amplification in preoperative PW. Fifty-eight patients were excluded due to positive gene amplification, which suggested presence of preoperative peritoneal cancer cells. The 80 patients had mRNA amplification in PW after surgery. Amplification of multiple and single cancer-related marker genes was observed in 38 and 21 patients; 21 cases had marker-negative results. Five-year PRFS was 69.1%, 95.2%, and 100% in multi-marker-positive, single marker-positive, and marker-negative cases, respectively. Multi-marker-positive patients had significantly worse PRFS than the other groups (p < 0.05). Multivariate analysis in the Cox proportional hazards model identified multi-marker-positivity as an independent prognostic factor for PRFS (hazard ratio, 7.6; 95% confidence interval, 1.07-62.63; p = 0.046), and multi-marker-positive patients had significantly worse OS than other groups (p < 0.01). CONCLUSION: Multi-marker cancer-related gene amplification in PW is associated with worse prognosis in PRFS and OS even after a long follow-up; PRFS can be stratified by the number of genes amplified.

[Short- and Long-Term Effects of Palliative Stoma Creation on Quality of Life].

Palliative stoma creation for malignant gastrointestinal obstruction improves quality of life, and advances in chemotherapy have resulted in long-term survival after stoma creation. We reviewed early and late complications in 24 patients treated with palliative stoma creation. Results: 14 men(58%)and 10 women(42%)had a median age of 60 years. Twenty-three patients(96%)were able to eat more than a porridge diet postoperatively, and the median The ColoRectal Obstruction Scoring System(CROSS)improved from 1(0-3)to 4(2-4)(p<0.001). Postoperative complications(all Clavien-Dindo grades)were observed in 10 patients(42%), with a longer postoperative hospital stay in the complication group than in the group without complication(median 34 days: 17 days, p=0.026). When divided into long-term survivors and short- term survivors based on a median overall survival of 101 days, more stoma prolapse occurred in the long-term survivors(4 cases 33% vs 0 cases 0%, p=0.028), one of which required repair surgery. Conclusion: Long-term survivors after exploratory stoma creation are more likely to develop a stoma prolapse. Careful surgical manipulation and postoperative support system including stoma care are important.

The Comparison of Fecal Microbiota in Left-Side and Right-Side Human Colorectal Cancer.

INTRODUCTION: Microbiomes play a vital role in the development and progression of cancer. The clinical status, including prognosis, genetic mutations, and sensitivity to chemotherapy, differs depending on the location of colorectal cancer (CRC); however, the association between gut microbiota and the location of CRC is not entirely understood. This study was conducted to evaluate the differences in the gut microbiota in patients with CRC according to the location of the tumor. METHODS: Fifty-six patients who underwent surgery for CRC between August 2018 and November 2019 were included in the study. Three patients who had received neoadjuvant therapy or antibiotic treatment within 1 month before surgery were excluded. The metagenomes of microbiota in preoperative feces were assessed using the V3-V4 region of 16s rRNA amplicon sequences. RESULTS: The beta diversity of the Bray-Curtis distance was significantly higher in left-sided than in right-sided CRC. Fusobacterium predominated in left-sided CRC according to the linear discriminant analysis effect size method. Blautia, Eryspelotrichales, Holdemanella, Faecalibacterium, Subdoligranulum, and Dorea constituted the dominant intestinal flora in right-sided CRC. Pathway analysis revealed that L-lysine fermentation and cob(II)yrinate a,c-diamide biosynthesis I were predominant in left-sided CRC. DISCUSSION: This study demonstrated that fecal microbiota in left-sided CRC constitutionally and functionally differ from those in right-side CRC. These results will help to elucidate the biological differences according to tumor location and develop treatments for human CRC.

Comparison of self-expandable metallic stent placement followed by laparoscopic resection and elective laparoscopic surgery without stent placement for left-sided colon cancer.

AIM: Self-expandable metallic stent (SEMS) placement for obstructive colon cancer is widely performed as a bridge to surgery (BTS) procedure before resection. This study aimed to investigate the surgical and oncological results of laparoscopic elective surgery with or without SEMS placement to assess the efficacy of SEMS placement as a BTS. METHODS: We retrospectively analyzed consecutive patients with stage II, III, and IV left-sided colon cancer who underwent elective laparoscopic resection between 2013 and 2019. All patients were divided into two groups: with and without SEMS placement. RESULTS: The SEMS group included 24 patients, whereas the non-SEMS group included 86 patients. The serum hemoglobin and albumin levels were lower (P = .049, P = .03), and the serum leukocyte and C-reactive protein levels were higher (P < .0001, P = .022) in the SEMS group. The tumor diameter and tumor circumferential rate were higher in the SEMS group (both P < .0001). No significant differences were observed in operation time, blood loss, postoperative complications, or postoperative hospital stay. After 1:1 propensity score matching, 15 patients in the SEMS group were compared with 15 patients in the non-SEMS group. The 3-year overall survival rates of the SEMS and non-SEMS groups were 87.5% and 88.9%, respectively (P = .97). The 3-year recurrence-free survival rates of the SEMS and non-SEMS groups were 58.2% and 81.7%, respectively (P = .233). No significant difference was found in the sites of recurrence. CONCLUSION: The perioperative and long-term outcomes of SEMS placement as a BTS before laparoscopic resection could be acceptable compared with other elective laparoscopic operations without SEMS placement.

INI1-negative colorectal undifferentiated carcinoma with rhabdoid features and postoperative rapidly growing liver metastases: a case report and review of the literature.

BACKGROUND: Malignant tumors with rhabdoid features are extremely rare. They can occur in various organs, including the gastrointestinal tract, with common clinical features of high malignancy and poor prognosis. CASE PRESENTATION: A 41-year-old man visited our hospital complaining of lower abdominal pain and fever. Computed tomography (CT) revealed two wall-thickening lesions in the rectum and sigmoid colon, with the latter invading the small intestine and abdominal wall. Lymph nodes were swollen in the sigmoid mesocolon and at the roots of the inferior mesenteric artery. Colonoscopy revealed a circular type 3 lesion in the sigmoid colon and a semicircular type 2 lesion in the rectum. Biopsies of the sigmoid colon and rectum lesions revealed poorly and moderately differentiated adenocarcinoma cells, respectively. The sigmoid colon, rectum, invaded small intestine, and abdominal wall were resected; lymph node dissection was also performed. Histopathological finding of the sigmoid colon lesion revealed that the tumor cells had poor connectivity with each other, and each cell had eosinophilic cytoplasm and a polymorphic nucleus. These characteristics are termed rhabdoid features, because the morphology of these cells is similar to that of rhabdomyosarcoma tumor cells. Immunohistochemical examination showed that the tumor cells were positive for both epithelial (cytokeratin AE1/AE3) and mesenchymal cell markers (vimentin); however, they were negative for integrase interactor 1 (INI1). Therefore, the sigmoid colorectal cancer was diagnosed as an INI1-negative undifferentiated carcinoma with rhabdoid features. The patient continued to experience high fever after surgery; thus, we performed an abdominal CT scan that revealed cystic lesions in the liver 4 days after surgery. These were absent in the positron emission tomography (PET)-CT scan performed 14 days before surgery. These tumors grew rapidly, and fine needle aspiration cytology revealed that they were undifferentiated carcinomas compatible with metastatic lesions from the undifferentiated carcinoma with rhabdoid features from the sigmoid colon. Chemotherapy was administered but was not effective. The patient died 60 days after surgery. CONCLUSIONS: INI1-negative colorectal undifferentiated carcinomas with rhabdoid features are extremely rare, have high histological malignancy, and a poor prognosis. Chemotherapy is not effective. Effective systemic therapy is desired.

[A Case of Intussusception Due to Juvenile Colorectal Cancer with Suspected Lynch Syndrome].

A 20-year-old man presenting with abdominal pain and distension from 3 months ago was admitted to our hospital. Colonoscopy showed a type 1 tumor in the transverse colon. The biopsy was moderately differentiated adenocarcinoma. Abdominal enhanced CT revealed intussusception associated with the tumor. After non-invasive reduction of intussusception was performed, a full-body examination revealed no findings suggestive of distant metastases or other Lynch syndrome- related tumors. We performed laparoscopic right hemicolectomy. Lynch syndrome was suspected based on his family history, MMR protein immunohistochemistry and MSI-High, but genetic testing was rejected due to cost reasons. If young people have chronic abdominal symptoms and a family history of suspected hereditary colorectal cancer, a close examination of colon cancer should be performed.

The Elevation in Preoperative Procalcitonin Is Associated with a Poor Prognosis for Patients Undergoing Resection for Colorectal Cancer.

BACKGROUND: Procalcitonin (PCT) is a well-known marker for bacterial infection; however, the clinical significance of PCT in the long-term prognosis after colorectal cancer (CRC) surgery remains unclear. METHODS: This is a retrospective review of 277 patients that underwent CRC surgery to investigate the relationship between preoperative PCT, clinicopathological condition, cancer-specific overall survival (OS), and relapse-free survival (RFS). RESULTS: Median follow-up interval was 5.0 years in all patients. Thirty-six patients developed recurrence, and 46 patients died due to recurrences or metastases of CRC. Preoperative PCT levels were highest in Stage IV patients. The cancer-specific OS in patients with Stage IV/PCT ≤0.05 ng/mL was significantly higher than those with Stage IV/PCT >0.05 ng/mL (3 years survival; 42.3 vs. 14.3%, p = 0.0413). On multivariate analysis, gender, TNM classification, and PCT were identified as significant risk factors for cancer-specific OS in patients with Stage I-III CRC. The cancer-specific OS rate of these patients with PCT ≥0.08 ng/mL, compared with PCT <0.08 ng/mL, was significantly decreased (5 years survival; 59.1 vs. 92.7%, p < 0.0001). TNM classification was finally identified as an independent risk factor for cancer-specific RFS in these patients by multivariate analysis. CONCLUSION: High preoperative PCT values in CRC patients appeared to be associated with poor OS but not RFS following surgical treatments.

IgG4-related focal retroperitoneal fibrosis in ureter suggestive of colon cancer recurrence and resected laparoscopically: a case report.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a novel disease concept of unknown cause that is characterized by abundant infiltration of IgG4-positive cells, mass-forming lesions, and elevated serum IgG4 levels. The infiltration of IgG4-positive plasma cells and lymphocytes causes swelling, inflammation, fibrosis, and obliterative phlebitis in multiple organs. On the other hand, IgG4-RD occurring in the ureters has rarely been reported. To our knowledge, this is the first report of laparoscopic partial ureteral resection for IgG4-related focal retroperitoneal fibrosis in a ureter with suspected colon cancer recurrence. CASE PRESENTATION: A 72-year-old man with a history of sigmoid colon cancer visited Shiga University of Medical Science Hospital for regular follow-up in December 2019. Enhanced abdominal computed tomography revealed a mass involving the left ureter. Furthermore, fluorine-18 fluorodeoxyglucose positron emission tomography showed significant accumulation of fluorodeoxyglucose uptake in the same region. Due to the possibility of colon cancer recurrence, a laparoscopic excisional biopsy with partial ureteral resection was performed. Histologically, IgG4-positive plasma cell infiltration exceeding 10 cells per high-power field and a high ratio of IgG4-positive/IgG-positive cells exceeding 40% were observed. The postoperative serum IgG4 level was 384 mg/dL. With the application of these findings to the diagnostic algorithm in the comprehensive diagnostic criteria for IgG4-RD, the mass-forming lesion was diagnosed as definitive IgG4-related focal retroperitoneal fibrosis. CONCLUSIONS: IgG4-RD should be considered in the differential diagnosis of retroperitoneal lesions. Moreover, laparoscopic surgery may be useful for making the diagnosis in difficult-to-biopsy cases.

[A Case of Simultaneous Double Cancer with Gastric Metastasis of Breast Cancer and Lung Cancer].

A 60s female with complaint of epigastric discomfort revealed 0-Ⅱb lesion in gastric fornix on upper gastrointestinal endoscopy and exhibited signet-ring cell carcinoma on histopathologic examination of biopsy specimens. A thoracoabdominal CT scan suggested tumors in right breast and left lung, and biopsy revealed invasive lobular carcinoma and primary lung adenocarcinoma, respectively. As results of multidisciplinary discussion of the treatment strategy for triple cancers, it was decided to perform robotic proximal gastrectomy, D1+ lymph node dissection, and esophagogastrostomy. The gastric lesion was diagnosed as gastric metastasis of breast cancer(T2N1M1, Stage Ⅳ)because immunohistochemical staining findings showed ER(+), GCDFP-15(+), and GATA-3(+). Two months later, she underwent the left upper lobectomy, and was diagnosed with lung acinar adenocarcinoma(pT2N0M0, pStage ⅠB). Six months after gastrectomy, she is currently on hormone therapy with aromatase inhibitors for breast cancer.

The impact of pharmacological thromboprophylaxis and disease-stage on postoperative bleeding following colorectal cancer surgery.

BACKGROUND: Pharmacological thromboprophylaxis after colorectal cancer (CRC) surgery is internationally recommended for venous thromboembolism (VTE) prevention. The aim of this retrospective study was to evaluate the risk factors of postoperative bleeding after elective surgery for patients with primary CRC receiving pharmacological thromboprophylaxis of fondaparinux or enoxaparin. METHODS: We experienced consecutive 266 patients who underwent elective surgery for CRC during the study period. Finally, the medical records of 218 patients with CRC administrated fondaparinux or enoxaparin following surgery were retrospectively reviewed to evaluate symptomatic VTE until 28 days and postoperative bleeding comparing perioperative D-dimer levels. RESULTS: The significant differences in TNM classification staging and type of thromboprophylaxis were observed between postoperative bleeding-negative and bleeding-positive group. There was no statistical significance among other backgrounds of patients between the two groups. One case (0.46%) of symptomatic VTE and total 11 cases (5%) of postoperative bleeding were observed. In the univariate analysis, fondaparinux thromboprophylaxis and early disease-stage CRC (stages 0 and I) were associated with risk for postoperative bleeding. Multivariate analysis revealed that fondaparinux thromboprophylaxis was identified as an independent risk factor of postoperative bleeding. Moreover, preoperative levels of D-dimer in patients with stage IV CRC were significantly higher than those with the other stages. The significant elevation in preoperative D-dimer was also observed in patients with stage II CRC compared to those with stage I CRC. Perioperative levels of D-dimer in patients with advanced disease-stage CRC (stages II, III, and IV) were significantly higher than those in patients with early disease-stage CRC. CONCLUSIONS: Fondaparinux administration and early disease-stage CRC appeared to be risk factors for postoperative bleeding in patients with pharmacological thromboprophylaxis undergoing surgical treatment for CRC. Patients' hypercoagulative condition depending on disease progression of CRC might be related to the occurrence of postoperative bleeding following CRC surgery.

[Study of Eight Cases of Retroperitoneal Liposarcoma].

Retroperitoneal liposarcoma is a relatively rare disease, with a high recurrence rate and poor prognosis. We encountered 8 patients with retroperitoneal liposarcoma who underwent surgery in Shiga University of Medical Science Hospital. We often encounter elderly male patients without symptoms. Of the 8 patients, 6 received extensive resection that included the surrounding organs or tissues; however, 3 patients demonstrated positive surgical margins, which resulted in liposarcoma recurrence. Despite the additional resection in the 3 recurrent cases, all the patients had a tumor relapse. One patient with an unresectable tumor received chemotherapy. The other patients received surgical treatment 3 times. One patient developed an unresectable relapse after receiving chemotherapy. Another patient attained long-term survival by adjuvant chemoradiotherapy combined with 3 surgeries. Aggressive surgical resection to achieve a negative surgical margin and careful postoperative follow-up seem important for the treatment of retroperitoneal liposarcoma. This study suggests that postoperative adjuvant therapy may contribute to the improvement of prognosis. Further findings must be accumulated to clarify the significance of postoperative adjuvant therapies in the future.

Fibrosis in metastatic lymph nodes is clinically correlated to poor prognosis in colorectal cancer.

BACKGROUND: Tumor microenvironment including fibrosis has a pivotal role in cancer growth and distant metastasis. Fibrosis is a known risk factor for carcinogenesis, but its biological role in disease invasion and metastasis in colorectal cancer (CRC) remains unclear. In particular, there is no report on how fibrosis of metastatic lymph nodes (MLNs) in CRC contributes to prognosis. METHODS: We reviewed 94 colorectal adenocarcinoma patients with MLNs who underwent colectomy. Both the primary tumors and MLNs were analyzed for alpha-smooth muscle actin (α-SMA) expression and collagen deposition. RESULTS: Higher α-SMA expression and collagen deposition in MLNs were associated with significantly shorter relapse-free survival and overall survival in CRC patients. α-SMA expression in MLNs (HR, 1.53; p = 0.034) was independent predictive factor of overall survival in multivariate Cox proportional hazards regression analysis of clinicopathological factors. In the Stage III patient subgroup, α-SMA expression in MLNs was a strong prognostic marker (HR, 3.01; p = 0.006). On the other hand, higher α-SMA expression and collagen deposition in primary tumors were associated with short overall survival, but they were not significant factors in multivariate Cox regression analyses. In MLNs, the podoplanin signals co-localized with α-SMA expression and were confirmed by the dual immunofluorescence staining, implying that the MLN stromal cells were fibroblastic reticular cells. CONCLUSION: Both high collagen deposition and high α-SMA expression in MLNs predicted poor prognosis in CRC.

[A Case of Combined Treatment Approach of Endoscopic Submucosal Dissection and Transanal Minimally Invasive Surgery for Radiation Induced Rectal Cancer].

It is hard to determine treatment strategy for radiation induced carcinoma, because radiation cause fibrosis to adjacent organ.The patient was in the 70's, who underwent 70 Gy radiation therapy for prostate cancer 5 years ago.He visited hospital because of fecal occult blood.Endoscopic examination revealed laterally spreading tumor(LST)in rectal front wall, and he referred to our hospital in purpose of endoscopic submucosal dissection(ESD).We performed ESD for LST, following transanal minimally invasive surgery to suture mucosal defect.He discharged out hospital 9 days after operation without any adverse event except anal pain.Suturing of mucosal defect after ESD might be potent to prevent postoperative complications in radiation induced rectal cancer.

[A Case of Gastric Cancer Underwent Two-Stage Gastrectomy after Chemotherapy-Induced Perforation].

A 70's man presenting with a chief complaint of stomachache was found to have advanced gastric cancer with a deep ulcer and some lymph-node metastases. We decided performing a curative operation after 2 courses of S-1 plus cisplatin. On the first course day 13 of chemotherapy, he complained of severe epigastralgia, and we diagnosed as generalized peritonitis due to perforation of gastric cancer. We performed an urgent laparoscopic operation, which made perforation simple closure and omentopexy. Curative distal gastrectomy with D2 lymph node dissection was successfully performed on postoperative day 16.