Comparison of clinicopathological and survival features of right and left colon cancers.

Purpose: Right-sided colon cancers (RCCs) and left-sided colon cancers (LCCs) have different embryological, epidemiological, physiological, pathological, genetic, and clinical characteristics, which result in differences in the course, prognosis, and outcome of disease. This study aimed to compare RCCs and LCCs regarding clinicopathological and survival characteristics.

Methods: The present retrospective study included data of patients who were followed-up and treated for colon cancer from 2008 through 2017. Rectosigmoid, descending colon, and splenic flexure tumors were considered LCC, whereas hepatic flexure and ascending colon tumors were considered RCC. Tumors were staged according to the American Joint Committee on Cancer classification.

Results: The study included 1725 patients (female, 58.7%) having colon cancer with a mean age of 64±12 years. Of the patients, 83.2% (n=1436) had LCC and 16.8% (n=289) had RCC. The rate of patients aged ≥65 years and the rate of patients with a family history of colon cancer were higher in the RCC patients. The rate of metastatic patients was 29.1% in the RCC group and 23.2% in the LCC group (p=0.087). The median follow-up period was 18 months in the RCC group and 23 months in the LCC group (p=0.011). Although the median survival time was higher in the LCC group (62 vs. 43 months), no significant difference was determined between the RCC and LCC groups in terms of survival.

Conclusions: There are numerous clinicopathological differences between RCC and LCC and these differences are reflected in prognostic and survival differences among certain subgroups.