Differences Between Right and Left Colon Cancers in Terms of Clinicopathological Features and Long-term Oncological Outcomes

Aim: Although there are clinical differences in colon cancer (CC) according to the location of the tumor, the differences between right and left CC in terms of survival are not clear. Our aim was to analyze the clinicopathological differences between right and left CC and to investigate the effect of primary tumor location on recurrence and survival. Method: The data of 330 patients who underwent curative surgery for right (n=155) or left (n=175) colon cancer between 2011 and 2018 were retrospectively analyzed. Demographic characteristics, surgical data, pathological data, recurrence and survival rates of the patients were examined and the two groups were compared in terms of these parameters. Results: Male to female ratio was significantly higher and operative time was significantly longer in the left CC than in the right CC. The mean number of harvested lymph nodes was significantly higher in the right CC than the left CC (32±3 and 27±9, respectively, p=0.001). Compared to patients with left CC, those with right CC had higher tumor diameter and tumor volume, had more poorly differentiation and tended to have more mucinous and medullary type cancer. As a result of a median follow-up of 54 months, it was determined that the 5-year overall survival in stage I-III patients was worse in the right CC than in the left CC. Especially in stage III patients, both overall and disease-free survival rates were found to be statistically significantly lower in the right CC compared to the left CC (In stage III disease, overall survival was 66.9% in right CC and 81.8% in left CC, p=0.03; disease-free survival was 54.2% in right CC and 70.6% in left CC, p=0.04). Conclusion: There may be clinicopathological and prognostic differences in CC depending on the location of the tumor. As a result of the long followup period in our case series, the prognosis in the right CC was worse, especially in stage III patients.