Leveraging a KRAS-based signature to predict the prognosis and drug sensitivity of colon cancer and identifying SPINK4 as a new biomarker.

KRAS is one of the leading mutations reported in colon cancer. However, there are few studies on the application of KRAS related signature in predicting prognosis and drug sensitivity of colon cancer patient. We identified KRAS related differentially expressed genes (DEGs) using The Cancer Genome Atlas (TCGA) database. A signature closely related to overall survival was recognized with Kaplan-Meier survival analysis and univariate cox regression analysis. Then we validated this signature with overall expression score (OE score) algorithm using both scRNA-seq and bulk RNA-seq data. Based on this signature, we performed LASSO cox regression to establish a prognostic model, and corresponding scores were calculated. Differences in genomic alteration, immune microenvironment, drug sensitivity between high- and low-KRD score groups were investigated. A KRAS related signature composed of 80 DEGs in colon cancer were recognized, among which 19 genes were selected to construct a prognostic model. This KRAS related signature was significantly correlated with worse prognosis. Furthermore, patients who scored lower in the prognostic model presented a higher likelihood of responding to chemotherapy, targeted therapy and immunotherapy. Furthermore, among the 19 selected genes in the model, SPINK4 was identified as an independent prognostic biomarker. Further validation in vitro indicated the knockdown of SPINK4 promoted the proliferation and migration of SW48 cells. In conclusion, a novel KRAS related signature was identified and validated based on clinical and genomic information from TCGA and GEO databases. The signature was proved to regulate genomic alteration, immune microenvironment and drug sensitivity in colon cancer, and thus might serve as a predictor for individual prognosis and treatment.

FOXD1 promotes chemotherapy resistance by enhancing cell stemness in colorectal cancer through ß­catenin nuclear localization.

Forkhead box D1 (FOXD1) serves a critical role in colorectal cancer (CRC). FOXD1 expression is an independent prognostic factor in patients with CRC; however, the molecular mechanism and signaling pathway of FOXD1 that regulates cell stemness and chemoresistance has not been fully characterized. The aim of the present study was to further validate the effect of FOXD1 on the proliferation and migration of CRC cells, and to delve into the possible potential of FOXD1 in the clinical treatment of CRC. The effect of FOXD1 on cell proliferation was assessed using Cell Counting Kit 8 (CCK­8) and colony formation assays. The effect of FOXD1 on cell migration was assessed by wound­healing and Transwell assays. The effect of FOXD1 on cell stemness was assessed by spheroid formation in vitro and limiting dilution assays in vivo. The expression of stemness associated proteins, leucine rich repeat containing G protein­coupled receptor 5 (LGR5), OCT4, Sox2 and Nanog, and epithelial­mesenchymal transition associated proteins, E­cadherin, N­cadherin and vimentin, were detected by western blotting. Proteins interrelationships were assessed by a co­immunoprecipitation assay. Oxaliplatin resistance was assessed using CCK­8 and apoptosis assays in vitro, and using a tumor xenograft model in vivo. By constructing FOXD1 overexpression and knockdown stably transfected strains of colon cancer cells, it was revealed that the overexpression of FOXD1 increased CRC cell stemness and chemoresistance. By contrast, knockdown of FOXD1 produced the opposite effects. These phenomena were caused by the direct interaction between FOXD1 and ß­catenin, thus promoting its nuclear translocation and the activation of downstream target genes, such as LGR5 and Sox2. Notably, inhibition of this pathway with a specific ß­catenin inhibitor (XAV­939) could impair the effects induced by the overexpression of FOXD1. In summary, these results indicated that FOXD1 may promote cell stemness and the chemoresistance of CRC by binding directly to ß­catenin and enhancing ß­catenin nuclear localization; therefore, it may be considered a potential clinical target.

IL-17A-mediated mitochondrial dysfunction induces pyroptosis in colorectal cancer cells and promotes CD8 + T-cell tumour infiltration.

BACKGROUND: Interleukin-17A (IL-17A), a proinflammatory cytokine primarily secreted by Th17 cells, γδT cells and natural killer T (NKT) cells, performs essential roles in the microenvironment of certain inflammation-related tumours by regulating cancer growth and tumour elimination proved in previous literature. In this study, the mechanism of IL-17A that induces mitochondrial dysfunction promoted pyroptosis has been explored in colorectal cancer cells. METHOD: The records of 78 patients diagnosed with CRC were reviewed via the public database to evaluate clinicopathological parameters and prognosis associations of IL-17A expression. The colorectal cancer cells were treated with IL-17A, and the morphological characteristics of those cells were indicated by scanning electron microscope and transmission electron microscope. After IL-17A treatment, mitochondrial dysfunction was tested by mitochondrial membrane potential (MMP) and reactive oxygen species (ROS). The expression of pyroptosis associated proteins including cleaved caspase-4, cleaved gasdermin-D (GSDMD), IL-1ß, receptor activator of nuclear NOD-like receptor family pyrin domain containing 3 (NLRP3), apoptosis-associated speck like protein containing a card (ASC), and factor-kappa B was measured through western blotting. RESULTS: Positive IL-17A protein expression was observed in CRC compared to the non-tumour tissue. IL-17A expression indicates a better differentiation, earlier stage, and better overall survival in CRC. IL-17A treatment could induce mitochondrial dysfunction and stimulate intracellular reactive oxygen species (ROS) production. Furthermore, IL-17A could promote pyroptosis of colorectal cancer cells and significantly increase the secretion of inflammatory factors. Nevertheless, the pyroptosis induced by IL-17A could be inhibited through the pre-treatment with Mito-TEMPO (a mitochondria-targeted superoxide dismutase mimetic with superoxide and alkyl radical scavenging properties) or Z-LEVD-FMK (caspase-4 inhibitor, fluoromethylketone). Additionally, after being treated with IL-17A, an increasing number of CD8 + T cells showed in mouse-derived allograft colon cancer models. CONCLUSION: IL-17A, as a cytokine mainly secreted by γδT cells in the colorectal tumour immune microenvironment, can regulate the tumour microenvironment in multiple ways. IL-17A could induce mitochondrial dysfunction and pyroptosis through the ROS/NLRP3/caspase-4/GSDMD pathway, and promote intracellular ROS accumulation. In addition, IL-17A can promote the secretion of inflammatory factors such as IL-1ß、IL-18 and immune antigens, and recruit CD8 + T cells to infiltrate tumours.

Retrospective research of neoadjuvant therapy on tumor-downstaging, post-operative complications, and prognosis in locally advanced rectal cancer.

BACKGROUND: Neoadjuvant therapy (NAT) is becoming increasingly important in locally advanced rectal cancer. Hence, such research has become a problem. AIM: To evaluate the downstaging effect of NAT, its impact on postoperative complications and its prognosis with different medical regimens. METHODS: Seventy-seven cases from Shanghai Ruijin Hospital affiliated with Shanghai Jiaotong University School of Medicine were retrospectively collected and divided into the neoadjuvant radiochemotherapy (NRCT) group and the neoadjuvant chemotherapy (NCT) group. The differences between the two groups in tumor regression, postoperative complications, rectal function, disease-free survival, and overall survival were compared using the χ 2 test and Kaplan-Meier analysis. RESULTS: Baseline data showed no statistical differences between the two groups, whereas the NRCT group had a higher rate of T4 (30/55 vs 5/22, P < 0.05) than the NCT groups. Twelve cases were evaluated as complete responders, and 15 cases were evaluated as tumor regression grade 0. Except for the reduction rate of T stage (NRCT 37/55 vs NCT 9/22, P < 0.05), there was no difference in effectiveness between the two groups. Preoperative radiation was not a risk factor for poor reaction or anastomotic leakage. No significant difference in postoperative complications and disease-free survival between the two groups was observed, although the NRCT group might have better long-term overall survival. CONCLUSION: NAT can cause tumor downstaging preoperatively or even complete remission of the primary tumor. Radiochemotherapy could lead to better T downstaging and promising overall survival without more complications.

Staged laparoscopic management of locally advanced gastric cancer with outlet obstruction.

BACKGROUND: The prognosis of patients with locally advanced gastric cancer with outlet obstruction is poor. Gastrectomy with curative intent is often initially impossible or difficult. OBJECTIVE: We report our experience of curative distal gastrectomy after laparoscopic gastrojejunostomy and fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) chemotherapy to examine the feasibility and safety of this modified strategy for locally advanced gastric cancer with outlet obstruction, initially deemed unresectable. METHODS: Between October 2017 and June 2019, 15 patients diagnosed with locally advanced gastric cancer with outlet obstruction sequentially underwent gastrojejunostomy, received four cycles of FLOT chemotherapy, and underwent laparoscopic distal gastrectomy with curative intent (R0 resection + D2 lymphadenectomy). Clinical data were retrospectively collected and analyzed. RESULTS: R0 resection was possible in 12/15 patients, laparoscopically in 11, and one conversion to laparotomy was necessary. There was no perioperative mortality in the 12 patients. Pathologic evaluation of the resected specimens revealed that complete tumor grade regression 1a (TRG1a), TRG1b, TRG2, and TRG3 occurred in 3, 2, 4, and 3 patients, respectively. CONCLUSION: This case series showed that curative surgical resection was feasible as a staged approach for patients with locally advanced gastric cancer with outlet obstruction, after initial staged gastrojejunostomy and chemotherapy.

Comparative study of oncologic efficacy of cephalomedial to lateral dissection versus medial to lateral dissection in laparoscopic total mesorectal excision for rectal cancer: An RCT study.

BACKGROUND AND OBJECTIVES: We compared the 3-year overall survival between cephalomedial-to-lateral approach proctectomy (CEMP) and medial-to-lateral approach proctectomy (MAP) in patients undergoing laparoscopic total mesorectal excision for rectal cancer. The advantages of CEMP and the clinical value of No. 253 lymph nodes resection have not been objectively analyzed in literature. METHODS: This was a prospective, two-arm, multicenter, single-blinded, randomized trial. The primary endpoint was 3-year overall survival, and secondary endpoints included safety, feasibility, oncological radicality (including number of No. 253 lymph nodes harvested), short-term outcome, 3-year disease-free survival, rate of postoperative complications, mortality, and rate of recurrence. RESULTS: From May 2016 to July 2020, 506 patients were enrolled-256 in the CEMP group and 250 in the MAP group. Comparison of overall survival and disease-free survival showed that there was treatment benefit in the CEMP group (28.22 ± 12.12 vs. 27.44 ± 13.06, p = 0.485; 27.24 ± 12.01 vs. 26.42 ± 12.81; p = 0.457). More No. 253 lymph nodes were harvested in the CEMP group, and cases with positive No. 253 lymph nodes had worse prognosis in stage III. Surgical safety was equal for both approaches. CONCLUSIONS: Dissection of No. 253 lymph nodes may be important to improve clinical prognosis, but further studies with larger samples are needed to confirm this finding.

Long-term Outcomes of Laparoscopy-assisted Gastrectomy for T4a Advanced Gastric Cancer: A Single-center Retrospective Study.

BACKGROUND: Laparoscopy-assisted gastrectomy (LAG) has been proven to be feasible and oncologically safe for early gastric cancer. Despite the rapid increase in the number of LAG cases, there are few reports on the long-term outcomes of T4a (serosalinvasion) gastric cancer after LAG. The aim of the present study was to evaluate the long-term clinical outcomes in patients with stage T4a gastric cancer after laparoscopic gastrectomy. MATERIALS AND METHODS: A total of 578 patients with gastric cancer were treated with LAG between February 2004 and December 2014. Among these patients, 224 patients were pathologically confirmed with T4a advanced gastric cancer. The clinical and follow-up data were retrospectively analyzed, the survival rates were estimated using the Kaplan-Meier method, and the risk factors for overall and disease-free survival (DFS) were evaluated by Cox regression. RESULTS: Among these 224 patients, 129 patients were above 60 years old, and the male-to-female ratio was 157:67. Furthermore, among these patients, 125 patients received laparoscopy-assisted distal gastrectomy, whereas 99 patients received laparoscopy-assisted total gastrectomy. Forty (17.90%) patients experienced postoperative complications according to the Clavien-Dindo classification. Median follow-up time was 32 months. Recurrence was observed in 99 (44.20%) patients. The cumulative 5-year overall survival (OS) and DFS rates were 47.20% and 43.60%, respectively. The 5-year OS and DFS rates were 72.50% and 70.00% for stage N0, 57.00% and 53.90% for stage N1, 41.60% and 37.00% for stage N2, and 23.30% and 21.30% for stage N3, respectively. In the univariate analysis, tumor size, tumor location, N stage and metastatic lymph node ratio (MLR) were correlated with OS and DFS. The MLR was identified as an independent predictor for OS (P<0.05; hazard ratio=1.828; 95% confidence interval, 1.353-2.469) and DFS (P<0.05; hazard ratio=1.197; 95% confidence interval, 0.945-1.516). CONCLUSIONS: The long-term outcomes of LAG for T4a (M0) gastric cancer were acceptable, compared with previous reports. Therefore, this treatment could be considered as an alternative operative approach for T4a gastric cancer. The MLR was an independent predictor for OS and DFS.

CXCL5 induces tumor angiogenesis via enhancing the expression of FOXD1 mediated by the AKT/NF-κB pathway in colorectal cancer.

The mechanisms underlying the role of CXCL5 in tumor angiogenesis have not been fully defined. Here, we examined the effect of CXCL5 on tumor angiogenesis in colorectal cancer (CRC). Immunohistochemistry was used to monitor the expression of CXCL5 and CD31 in CRC patients' tissues. HUVEC cell lines stably transfected with shCXCR2 and shFOXD1 lentivirus plasmids were used in an in vitro study. Based on some molecular biological experiments in vitro and in vivo, we found that CXCL5 was upregulated in tumor tissues and that its level positively correlated with the expression of CD31. Next, we used recombinant human CXCL5 (rhCXCL5) to stimulate HUVECs and found that their tube formation ability, proliferation, and migration were enhanced by the activation of the AKT/NF-κB/FOXD1/VEGF-A pathway in a CXCR2-dependent manner. However, silencing of CXCR2 and FOXD1 or inhibition of the AKT and NF-κB pathways could attenuate the tube formation ability, proliferation, and migration of rhCXCL5-stimulated HUVECs in vitro. rhCXCL5 can promote angiogenesis in vivo in Matrigel plugs, and the overexpression of CXCL5 can also increase microvessel density in vivo in a subcutaneous xenotransplanted tumor model in nude mice. Taken together, our findings support CXCL5 as an angiogenic factor that can promote cell metastasis through tumor angiogenesis in CRC. Furthermore, we propose that FOXD1 is a novel regulator of VEGF-A. These observations open new avenues for therapeutic application of CXCL5 in tumor anti-angiogenesis.

Bone marrow-derived mesenchymal stromal cells promote colorectal cancer cell death under low-dose irradiation.

BACKGROUND: Radiotherapy remains one of the cornerstones to improve the outcome of colorectal cancer (CRC) patients. Radiotherapy of the CRC not only help to destroy cancer cells but also remodel the tumour microenvironment by enhancing tumour-specific tropism of bone marrow-derived mesenchymal stromal cell (BM-MSC) from the peripheral circulation. However, the role of local MSCs and recruited BM-MSC under radiation were not well defined. Indeed, the functions of BM-MSC without irradiation intervention remained controversial in tumour progression: BM-MSC was previously shown to modulate the immune function of major immune cells, resulting in an impaired immunological sensitivity and to induce an increased risk of tumour recurrence. In contrast, it could also secrete various cytokines and possess anticancer effect. METHODS: Three co-cultivation modules, 3D culture modules, and cancer organoids were established. The induction of cytokines secretion in hBM-MSCs after irradiation was analysed by ELISA array and flow cytometry. AutoMac separator was used to separate hBM-MSC and CRC automatically. Cells from the co-cultured group and the control group were then irradiated by UV-C lamp and X-ray. Proliferation assay and viability assay were performed. RESULTS: In this study, we show that BM-MSCs can induce the EMT progression of CRC cells in vitro. When irradiated with low doses of ultraviolet radiation and X-rays, BM-MSCs show an anti-tumour effect by secreting certain cytokine (TNF-α, IFN-γ) that lead to the inhibition of proliferation and induction of apoptosis of CRC cells. This was further verified in a 3D culture model of a CRC cell in vitro. Furthermore, irradiation on the co-culture system induced the cleavage of caspase3, and attenuated the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/AKT and extracellular signal-regulated kinase in cancer cells. The signal pathways above might contribute to the cancer cell death. CONCLUSIONS: Taken together, we show that BM-MSC can potentially promote the effect of radiotherapy in CRC.

CCR6 promotes tumor angiogenesis via the AKT/NF-κB/VEGF pathway in colorectal cancer.

Chemokines and chemokine receptors play an important role in tumorigenesis. Angiogenesis is a vital part of the occurrence, development and metastasis of cancer. CCR6 is an important factor during tumor progression; however, its function in tumor angiogenesis is not fully understood. In our study, we found that CCR6 was significantly overexpressed in colorectal cancer (CRC) tissues and predicted a poor prognosis in CRC patients. We then verified the function of CCR6 on tumor angiogenesis in vivo and in vitro. We observed that silencing CCR6 could decrease angiogenesis by inhibiting the proliferation and migration of human umbilical vein endothelial cells (HUVECs), whereas overexpression of CCR6 can promote angiogenesis. Additionally, we investigated the molecular mechanisms and demonstrated that activation of the AKT/NF-κB pathway maybe involved in CCR6-mediated tumor angiogenesis, which was able to promote the secretion of vascular endothelial growth factor A (VEGF-A). In conclusion, CCR6 facilitates tumor angiogenesis via the AKT/NF-κB/VEGF pathway in colorectal cancer. CCR6 inhibition may be a novel option for anti-vascular treatment in CRC.

Homogeneous pancreatic cancer spheroids mimic growth pattern of circulating tumor cell clusters and macrometastases: displaying heterogeneity and crater-like structure on inner layer.

PURPOSE: Pancreatic cancer 3D in vitro models including multicellular tumor spheroid (MCTS), single cell-derived tumor spheroid (SCTS), tissue-derived tumor spheroid, and organotypic models provided powerful platforms to mimic in vivo tumor. Recent work supports that circulating tumor cell (CTC) clusters are more efficient in metastasis seeding than single CTCs. The purpose of this study is to establish 3D culture models which can mimic single CTC, monoclonal CTC clusters, and the expansion of macrometastases. METHODS: Seven pancreatic ductal adenocarcinoma cell lines were used to establish MCTS and SCTS using hanging drop and ultra-low attachment plates. Spheroid immunofluorescence staining, spheroid formation assay, immunoblotting, and literature review were performed to investigate molecular biomarkers and the morphological characteristics of pancreatic tumor spheroids. RESULTS: Single cells experienced different growth patterns to form SCTS, like signet ring-like cells, blastula-like structures, and solid core spheroids. However, golf ball-like hollow spheroids could also be detected, especially when DanG and Capan-1 cells were cultivated with fibroblast-conditioned medium (p < 0.05). The size of golf ball-like hollow spheroids hardly grew after getting matured. Only DanG and Capan-1 could establish SCTS- and MCTS-derived hollow spheroids using hanging drop plates and ultra-low attachment plates. Other PDA cell lines could also establish tumor spheroid with hanging drop plates by adding methylated cellulose. Tumor spheroids derived from pancreatic cancer cell line DanG possessed asymmetrically distributed proliferation center, immune-checkpoint properties. ß-catenin, Ki-67, and F-actin were active surrounding the crater-like structure distributing on the inner layer of viable rim cover of the spheroids, which was relevant to well-differentiated tumor cells. CONCLUSIONS: It is possible to establish 3D CTC cluster models from homogenous PDA cell lines using hanging drop and ultra-low attachment plates. PDA cell line displays its own intrinsic properties or heterogeneity. The mechanism of formation of the crater-like structure as well as golf ball-like structure needs further exploration.

A modified uncut Roux-en-Y anastomosis in totally laparoscopic distal gastrectomy: preliminary results and initial experience.

OBJECTIVE: To investigate the safety and feasibility of totally laparoscopic uncut Roux-en-Y anastomosis in the distal gastrectomy with D2 dissection for gastric cancer. We also summarized the preliminary experience of totally laparoscopic uncut Roux-en-Y anastomosis. METHODS: A retrospective analysis was done in 51 cases of total laparoscopic uncut Roux-en-Y anastomosis in the distant gastrectomy with D2 dissection for gastric cancer in our hospital from September 2014 to December 2015. RESULTS: All of 51 cases underwent total laparoscopic uncut Roux-en-Y anastomosis. All the procedures were performed successfully. There were neither conversions to open surgery nor intraoperative complications in all 51 cases. In this study, the median operative time was 170 (135-210) min and the median time of anastomosis was 27 (24-41) min. The blood loss was 60 (30-110) ml. The time to flatus and length of postoperative hospital stay were 2 (1-3) days, and 8 (7-12) days, respectively. The mean lymph node harvest was 34 (18-49). One anastomotic bleeding occurred postoperatively which was cured by conservative treatment. No major postoperative complication occurred, such as anastomotic leak, anastomotic stenosis, and Roux stasis syndrome. After a short-term follow-up, no recanalization or reflux gastritis was encountered by endoscopy. CONCLUSION: The totally laparoscopic uncut Roux-en-Y anastomosis in distal gastrectomy with lymph node dissection for gastric cancer is safe and feasible, with a very low rate of recanalization and reflux gastritis.

Long-term outcomes and propensity score matching analysis: rectal cancer resection for patients with elevated preoperative risk.

BACKGROUND: It is still controversial about the treatment strategy for rectal cancer patients with elevated operative risk and elder rectal cancer patients. METHODS: This study presented a retrospective single center experience in rectal cancer proctectomy for high operative risk patients. High operative risk patient was defined as Cr-POSSUM > 5% combined with associated risk factors. 220 in 1477 consecutive patients met the inclusion criteria. RESULTS: 132 patients were selected (66:66) after propensity score matching. The total complication rate between conventional open rectal resection (71 %) and laparoscopic surgery (41%) was significantly different (p = 0.0005). There is a significantly positive correlation between open surgery and advanced Dindo Classification (p = 0.02). Cr-POSSUM is positively correlated with Dindo Classification (p = 0.01). There was no significant difference in survival rate among stage I~II, different age groups or different Cr-POSSUM score sub-groups. However, stage III-IV tumor patients in laparoscopic group experienced improved overall survival rate. (p < 0.0001). For patients with preoperative pulmonary or renal disease, patients in laparoscopic group also had better long term prognosis (p = 0.03, p = 0.049). CONCLUSIONS: The results demonstrate the potential advantages of laparoscopic rectal cancer resection for high operative risk patients, especially for the patients with preoperative respiratory or renal disease and stage III cancer.

Laparoscopic Complete Mesocolic Excision for Stage II/III Left-Sided Colon Cancers: A Prospective Study and Comparison with D3 Lymph Node Dissection.

BACKGROUND: To investigate the similarities and differences of laparoscopic complete mesocolic excision (CME) to a colon resection with a D3 lymphadenectomy for the stage II/III left-sided colon carcinoma. METHODS: Patients between July 2011 and August 2014 were randomized into D3 and CME groups. Mesenteric area, log odds of positive lymph nodes (LODDS), and other operative parameters were collected and assessed. RESULTS: The average specimen sizes were 5730 ± 828 mm(2) in superior rectal artery (SRA)-preserving D3, 8145 ± 1022 mm(2) in SRA-nonpreserving D3, and 8745 ± 1039 mm(2) in the CME group; the differences were significant (P < .0001). The number of lymph nodes collected from CME specimens was larger, but the CME specimens did not contain an elevated value of LODDS or positive nodes or lymph node ratio (LNR). There were also no significant differences between recovery times of bowel function. Although it took more operation time in D3 approach, especially in SRA-preserving D3 operation, the difference was not significant. Concerning the leakage rate (P = .34) and vessel-related complications (P = .64), there were no significant differences either. CONCLUSIONS: Both standard D3 resection and CME could achieve a high quality of mesocolic plane grade for stage II/III colon cancer. The LODDS and LNR were comparable, and those were not relevant to mesenteric size.

Comparison of non-schistosomal rectosigmoid cancer and schistosomal rectosigmoid cancer.

AIM: To compare the clinicopathological features of patients with non-schistosomal rectosigmoid cancer and schistosomal rectosigmoid cancer. METHODS: All the patients with rectosigmoid carcinoma who underwent laparoscopic radical surgical resection in the Shanghai Minimally Invasive Surgical Center at Ruijin Hospital affiliated to Shanghai Jiao-Tong University between October 2009 and October 2013 were included in this study. Twenty-six cases of colonic schistosomiasis diagnosed through colonoscopy and pathological examinations were collected. Symptoms, endoscopic findings and clinicopathological characteristics were evaluated retrospectively. RESULTS: There were no significant differences between patients with and without schistosomiasis in gender, age, CEA, CA19-9, preoperative biopsy findings or postoperative pathology. Patients with rectosigmoid schistosomiasis had a significantly higher CA-125 level and a larger proportion of these patients were at an early tumor stage (P = 0.003). Various morphological characteristics of schistosomiasis combined with rectosigmoid cancer could be found by colonoscopic examination: 46% were fungating mass polyps, 23% were congestive and ulcerative polyps, 23% were cauliflower-like masses, 8% were annular masses. Only 27% of the patients were diagnosed with rectal carcinoma preoperatively after the biopsy. Computed tomography (CT) scans showed thickened intestinal walls combined with linear and tram-track calcifications in 26 patients. CONCLUSION: Rectosigmoid carcinoma combined with schistosomiasis is associated with higher CA-125 values and early tumor stages. CA-125 and CT scans have a reasonable sensitivity for the accurate diagnosis.

Challenge or opportunity: outcomes of laparoscopic resection for rectal cancer in patients with high operative risk.

This study investigated the impact of laparoscopic rectal cancer resection for patients with high operative risk, which was defined as American Society of Anesthesiology (ASA) grades III and IV. This study was conducted at a single center on patients undergoing rectal resection from 2006 to 2010. After screening by ASA grade III or IV, 248 patients who met the inclusion criteria were identified, involving 104 open and 144 laparoscopic rectal resections. The distribution of the Charlson Comorbidity Index was similar between the two groups. Compared with open rectal resection, laparoscopic resection had a significantly lower total complication rate (P<.0001), lower pain rate (P=.0002), and lower blood loss (P<.0001). It is notable that the two groups of patients had no significant difference in cardiac and pulmonary complication rates. Thus, these data showed that the laparoscopic group for rectal cancer could provide short-term outcomes similar to those of their open resection counterparts with high operative risk. The 5-year actuarial survival rates were 0.8361 and 0.8119 in the laparoscopic and open groups for stage I/II (difference not significant), as was the 5-year overall survival rate in stage III/IV (P=.0548). In patients with preoperative cardiovascular or pulmonary disease, the 5-year survival curves were significantly different (P=.0165 and P=.0210), respectively. The cost per patient did not differ between the two procedures. The results of this analysis demonstrate the potential advantages of laparoscopic rectal cancer resection for high-risk patients, although a randomized controlled trial should be conducted to confirm the findings of the present study.

Learning curve and long-term outcomes of laparoscopy-assisted distal gastrectomy for gastric cancer.

OBJECTIVE: To discuss the learning curve of laparoscopy-assisted distal gastrectomy (LADG) with lymph node dissection and the oncological results and long-term outcomes of different periods in the learning stage. PATIENTS AND METHODS: One hundred twenty-four patients with gastric cancer who received LADG with lymph node dissection from January 2004 to December 2009 were retrospectively reviewed and analyzed. They were divided into three groups (A-C) according to different operative date: 41 were in Group A (early), 41 in Group B (middle), and 42 in Group C (laer). There were no significant statistical differences among the three groups with respect to age, gender, early/advanced gastric cancer, Union for International Cancer Control stage, and lymph node dissection. Then the following items were compared in these groups: operative time, blood loss, number of lymph nodes harvested, postoperative complications, postoperative hospital stay, and long-term survival. RESULTS: The operative time in Group A (235.0±50.3 minutes) was significantly longer than in Groups B (201.7±39.6 minutes) and C (199.0±44.7 minutes), but there was no significant difference between Groups B and C. The harvest of lymph nodes from Group A (11.0±5.5) was significantly less than from Groups B (16.3±9.2) and C (17.2±8.7), but there was no significant difference between Groups B and C. The postoperative hospital stay and complications, overall survival, and disease-free survival showed no difference among the three groups. CONCLUSIONS: The learning curve of gastrointestinal surgeons with experience of laparoscopic operation is about 40 cases. The oncological principles and long-term outcomes were not sacrificed during the learning stage.

Endoscopic management for the assessment and treatment of anastomotic bleeding in laparoscopic anterior resection for rectal cancer.

OBJECTIVE: To evaluate the impact of routine intraoperative endoscopy (IOE) on postoperative anastomotic bleeding of laparoscopic anterior resection (LAR) for rectal cancer, and to investigate the value of the IOE in terms of prevention and treatment of postoperative anastomotic bleeding. METHODS: Medical records of the 279 cases of LAR from January 2006 to December 2011 were retrospectively analyzed, of which postoperative anastomotic bleeding occurred in 18. Univariate analysis was taken to determine the possible influencing factors of the bleeding. Then related influencing factors were put into the multivariate logistic regression analysis to ultimately determine the independent influencing factors of anastomotic bleeding. The efficacy of treatments to the anastomotic bleeding was also evaluated. RESULTS: The incidence of anastomotic bleeding after LAR is 6.5% (18/279).The rates of anastomotic bleeding in lower tumor location group and upper tumor location group were 9.2% (16/173) and 1.9% (2/106), respectively, as in intraoperative colonoscopy and nonintraoperative colonoscopy group were 3.3% (5/151), and 10.2% (13/128), respectively. Comparing the location of the tumor, the coefficient of regression and relative risk value for lower tumor were 1.564 and 4.776. Comparing the intraoperative colonoscopy and nonintraoperative colonoscopy group, the value for intraoperative colonoscopy group were -1.085 and 0.338. Sex, age, tumor stage, pathologic type, and preventive ileostomy had no relevance with the anastomotic bleeding. In 18 cases of the anastomotic bleeding, 7 received conservative treatments, 9 underwent endoscopic treatment, and 2 underwent reoperation. All the 18 cases had reached hemostasis. CONCLUSION: IOE is an independent protective factor of anastomotic bleeding after LAR. Endoscopic hemostasis is recommended for an anastomotic bleeding after LAR for rectal cancer with a stapling technique.

Completely medial versus hybrid medial approach for laparoscopic complete mesocolic excision in right hemicolon cancer.

OBJECTIVE: To explore the feasibilities between operational approaches for laparoscopic complete mesocolic excision (CME) to right hemicolon cancer. METHODS: This prospective randomized controlled trial included patients admitted to a Shanghai minimally invasive surgical center to receive laparoscopic CME from September 2011 to January 2013 randomized into two groups: hybrid medial approach (HMA) and completely medial approach (CMA). The feasibilities and strategies of the two techniques were studied and compared. Furthermore, the operation time and vessel-related complications were designed to be the primary end points, and other operational findings, including the classification of the surgical plane and postoperative recovery, were designed to be the secondary end points for this study. RESULTS: After screening, 50 cases were allocated to the HMA group and 49 to the CMA group. Within the HMA group, there were 48 cases graded with mesocolic plane and 2 with intramesocolic plane. For the CMA group, there were 42 cases graded with mesocolic plane and seven with intramesocolic plane. The differences between the two were insignificant, as were the number of lymph nodes retrieved. The mean±standard deviation total operation time for the CMA group was 128.3 ± 36.4 min, which was significantly shorter than that for the HMA group, 142.6 ± 34.8 min. For the CMA group, the time involved in central vessel ligations and laparoscopic procedures was 58.5 %, 14.1 and 81.2 ± 23.5 min, respectively, which were shorter than the HMA group. The vessel-related complication rate was significantly higher in the HMA group. CONCLUSIONS: Laparoscopic CME via the total medial approach is technically feasible after the precise identification of the surgical planes and spaces for the right hemicolon. The procedure has a shorter operation time and fewer vessel-related complications.