| Background:The World Health Organization introduced the classification of colorectal cancers according to their histology. Histological subtypes were defined as classical adenocarcinomas, which account for the large majority of cases, and mucinous adenocarcinomas, signet-ring cell carcinomas, and other even less frequent forms (small cell carcinoma, squamous cell carcinoma, adenosquamous carcinoma, medullary carcinoma, and undifferentiated carcinoma).This classification exists in addition to the commonly used TNM staging and grading system and remains valid today. The histological subtype presumably plays a role in tumor biology and prognosis,it potentially represents entities with different biological behavior, aggressiveness,and prognosis. Because of relatively rare occurrence, the evaluation of the clinical impact of mucinous adenocarcinomas and signet-ring cell carcinomas is difficult. They both share the characters as young age, advanced tumor stage, and poor prognosis, but their different biological behaviors and distinct clinical characters has not be completely elucidated yet.Objective:To explore clinicopathological features, surgical treatment and prognosis of colorectal signet-ring cell carcinoma and mucinous carcinoma.Methods:Retrospective analysis and follow-up were made on 67 patients with colorectal signet-ring cell carcinoma and 179 patients with mucinous carcinoma treated in Department of gerneral surgery, Qilu Hospital of Shandong University from Jan.1992 to Dec.2008. Obtained data were analyzed by SPSS17.0. Related factors were underwent x2 analysis, survival analysis were estimated using Kaplan-Meier method and compared using the Log-rank test and multiple-factors COX analysis.Results:Colorectal signet-ring cell carcinoma were significantly different from mucinous carcinoma in age, tumor location, bowel obstruction, operative modus, tumor embolism, tumor infiltration and lymph node metastasis (P<0.05) while the difference of such characteristics as gender, preoperative carcinoembryonic antigen level and hepatic metastasis or not was not significant. Median survival time was 26 months in signet-ring cell carcinoma and 47 months in mucinous carcinoma and the difference is significant (P<0.05). Histological subtype and operative modus were independent prognostic factors based on a multivariate analysis of the Cox Proportional Hazards Model.Conclusion:Malignancy of colorectal signet-ring cell carcinoma is higher than mucinous carcinoma. Radical resection and palliative cytoreductive surgery can improve prognosis effectively. |
