Clinicoepidemiological Study and Survival Analysis of Right versus Left Sided Colon Cancer Patients

Abstract

Background: Recently, there is a great attention, about the clinicopathological differences between right and left colon cancer, and how much these differences will affect the outcomes of colon cancer patients. Many epidemiological studies have demonstrated, that tumor at the right and left colon, respectively, occur with different incidence in diverse region of the world. Differences in clinical presentation, patient's demographics, and tumor biology between right-and left-sided colon cancers have long been reported in the literatures. Methods: The current study was conducted in Clinical Oncology and Nuclear medicine department, Ain Shams University Hospitals, during the period from January 2011 to December 2015, data on all patients histologically confirmed with colon cancer, were evaluated right-and left-sided cancers were compared with regard to epidemiological, clinical and pathological parameters as well as survival data. Results: The study showed that, there was 129 patients, 70(54.2%) patients had left-sided colon cancers and 59(45.7%) patients had right-sided colon cancers, most of the cases were aged above 50 years 61.2%. Histopathological type was mainly adenocarcinoma 72.09%, moderately differentiated 79.8%, the mucinous carcinoma was more in right sided colon 56.25%. Comparison of progression free survival in stage IV, showed higher progression rate (58.3%) in right sided patients, than left sided patients (41.6%), this difference was not statistically significant. We also found that patients with right-sided colon cancer had a statistically significantly worse overall survival (OS) P value=0.019, than patients with left-sided colon cancer. We demonstrated that the differences in OS were significant only in patients with stage IV colon cancer. Conclusion: In conclusion, our results support evidence that there are differences in the biology and outcomes for right-and left-sided colon cancers. Significantly better survival is seen for metastatic colon cancer with a left-sided, and this was confirmed by multivariate analysis. This might have been due to several environmental and lifestyle factors, which contributed to this anatomical shift. The differences in genetic and molecular pathologic profiles in each side of the colon were observed. Stratification based on the primary site should be considered in the future for trials assessing survival for colon cancer.