Pathology and Prognosis of Colorectal Cancer

Introduction: Colorectal cancer (CRC) is one of the most common cancers in the world. During the past decades, survival of colorectal cancer patients has improved worldwide, however, it is not clear what factors have contributed to this development. This study was designed to evaluate the prognostic impact of a wide spectrum of pathologic parameters on survival rate in patients with colorectal cancer. Methods: 1127 patients with colorectal cancer who registered in one cancer registry in Iran were followed from their diagnostic date to Jan 1, 2007 (as failure time). Overall survival time was calculated by Kaplan-Meier method. The Cox proportional hazard model was used to identify the pathologic factors that could independently influence survival. Results: The overall survival rate at 5 years after diagnosis was 61%. Histology grade, status of regional lymph node metastasis, distant metastasis and pathologic tumor stage were related to survival rate according to univariate analysis. Nevertheless, in multivariate analysis, only histology grade, distant metastasis and tumor size had influence on survival of colorectal cancer patients. Conclusion: Generally the prognosis of disease is not poor; however, distant metastasis, poor differentiation and higher tumor size should be considered to have additional risks of death in colorectal cancer.