AIM:To compare the prognostic value of tumor-infiltrating lymphocytes (TILs) and CD3 + cells and CD20 + cells between schistosomal colorectal cancer (SCRC) and non-schistosomal CRC (NSCRC). BACKGROUND:Although schistosomiasis has been basically eliminated, it has not been completely extinction in China, and occasional outbreaks occur in Europe recently. The role of immune cells in the immune microenvironment of SCRC and NSCRC is remaining obscure, and the inflammation-based prognostic systems of SCRC has rarely been reported. METHODS:HE-stained sections of 349 colorectal cancer (CRC) tumors, which were completely resected, were evaluated for density of TILs. Meanwhile, we evaluated CD3 + T lymphocytes and CD20 + B lymphocytes by immunochemistry. The relationship of these infiltrating immune cells with clinicopathological features, including schistosomiasis, and clinical outcomes was evaluated, and the prognostic roles of TILs in SCRC and NSCRC were explored. RESULTS:Except for age (P < 0.0001), there were no significant differences between NSCRC and SCRC patients in clinicopathological features (P > 0.05). Beside, the positive expression pattern of sTILs, iTILs, CD3, and CD20 between NSCRC and SCRC patients was also similar (P > 0.05). In the whole cohort, sTILs and CD3 were defined as independent prognostic factors (P = 0.031 and P = 0.003, respectively). CD3 was an independent prognostic factor both in the NSCRC and SCRC set (P = 0.026 and P = 0.045, respectively). Higher sTILs, CD3, and CD20 were correlated with less aggressive tumor characteristics in the whole cohort and in subgroups. CONCLUSION:Although CD3 was an independent prognostic factor for both NSCRC and SCRC set, there were no significant differences between SCRC and NSCRC patients in sTILs, CD3, CD20, and in other clinicopathological features.

Abstract Aim: To investigate the relationship between schistosomiasis and tumour-infiltrating lymphocytes (TILs), and the prognostic value of the TILs in schistosomal colorectal cancer (CRC).Background: Although schistosomiasis has been basically eliminated, it has not been completely extinction in China and occasional outbreaks occur in Europe recently. The relationship between schistosomiasis and CRC is still obscure, and the inflammation based prognostic systems of schistosomal colorectal (SCRC) has rarely been reported.Methods: HE-stained sections of 351 CRC tumours, which were completely resected, were evaluated for density of total TILs (tTILs). Meanwhile, CD3+T lymphocytes and CD20+B lymphocytes were detected by immunochemistry. The relationship of these infiltrating immune cells with clinicopathological features, including schistosomiasis, and clinical outcomes were evaluated and the prognostic role of TILs in SCRC was explored.Results: Total TILs were negatively correlated with tumor size，pathological T stage, lymph node metastasis and number of tumor budding (p＜0.05). CD3+ T cell density was also inversely associated with tumor size, tumor budding and pathological T stage(p＜0.05). CD20+ B cells density was correlated with colonic perforin (p=0.034). In the whole cohort, multivariate analysis identified Schistosomiasis, tTILs and CD3 and CD20 as independent prognostic factors (p < 0.05). Patients were divided into two groups based on schistosomal infection status: Schistosomal CRC (SCRC set) and Non-schistosomal CRC (NSCRC set). Both tTILs (p=0.009) and CD3 (p=0.002) were independent prognostic factors in the NSCRC set. However, merely CD3 (p=0.0016) was independent predictor in the SCRC set. Conclusion: The prognostic roles of total TILs, and CD3+ T and CD20+ B cell were different in CRC patients with and without schistosomiasis, suggesting distinguished roles in the immune microenvironment in SCRC and NSCRC patients.

Aim: To investigate the relationship between schistosomiasis and tumour infiltrating lymphocytes (TILs), and the prognostic value of TILs in schistosomal colorectal cancer (CRC). Background: The association between TILs and CRC has long been suggested in the literature, but the association between TILs and schistosomiasis and the prognositic role of TILs in schistosomal CRC has never been reported previously. Methods: Hematoxylin and eosin (H&E)-stained sections of 351 CRC tumours, which were completely resected, were evaluated for density of TILs in intratumoural (iTIL) and stromal compartments (sTIL). Its relationship with clinicopathological features, including schistosomiasis, and clinical outcomes were evaluated and the prognostic role of sTILs in schistosomal CRC was explored. Results: Stromal TILs infiltration were correlated with smaller tumor size，less deeper pathological T stage, absence lymph node metastasis and less number of tumor budding (p＜0.05). However, there were no association between sTILs and shicstosomiasis. In the whole cohort, multivariate analysis identified gender, TNM Stage, Schistosomiasis, sTILs, lymph vascular invasion, lymph nodes positive for CRC were independent prognostic factors that associated with overall survival (OS) in CRC (p < 0.05). Patients were divided into two groups based on schistosomiasis infection status: colorectal cancer associated with schistosomiasis (CRC-NS set) and colorectal cancer without schistosomiasis (CRC-S set ). In the CRC-NS set, multivariate analysis demonstrated that tumor budding, sTILs, lymph vascular invasion, lymph nodes positive for CRC were independent prognostic factors that associated with OS (p < 0.05). However, there were no association between sTILs and OS in CRC-S set (p＞0.05). Besides, sTILs were associated with favorable OS in CRC-NS patients but not in CRC-S patients, regardless of age. Conclusion: Stromal TILs in the whole cohort and in the CRC-NS set were identified as an independent prognostic factor, but it was lack of prognostic role in schistosomal CRC. Stromal TILs was associated with less aggressive tumor features. Stromal TILs was associated with OS in CRC-NS patients but not in CRC-S patients, regardless of age.

Aim The purpose of this study was to compare clinicopathological features of patients with non-schistosomal and schistosomal colorectal cancer to explore the effect of schistosomiasis on colorectal cancer (CRC) patients' clinical outcomes. Methods Three hundred fifty-one cases of CRC were retrospectively analyzed in this study. Survival curves were constructed by using the Kaplan-Meier (K-M) method. Univariate and multivariate Cox proportional hazard regression models were performed to identify associations with outcome variables. Results Colorectal cancer patients with schistosomiasis (CRC-S) were significantly older (P< 0.001) than the patients without schistosomiasis (CRC-NS). However, there were no significant differences between CRC-S and CRC-NS patients in other clinicopathological features. Schistosomiasis was associated with adverse overall survival (OS) upon K-M analysis (P= 0.0277). By univariate and multivariate analysis, gender (P= 0.003), TNM stage (P< 0.001), schistosomiasis (P= 0.025), lymphovascular invasion (P= 0.030), and lymph nodes positive for CRC (P< 0.001) were all independent predictors in the whole cohort. When patients were stratified according to clinical stage and lymph node metastasis state, schistosomiasis was also an independent predictor in patients with stage III-IV tumors and in patients with lymph node metastasis, but not in patients with stage I-II tumors and in patients without lymph node metastasis. Conclusion Schistosomiasis was significantly correlated with OS, and it was an independent prognostic factor for OS in the whole cohort. When patients were stratified according to clinical stage and lymph node metastasis state, schistosomiasis was still an independently unfavorable prognosis factor for OS in patients with stage III-IV tumors or patients with lymph node metastasis.