Appraisal Of Prognostic Interaction Between Sidedness And Histology In Colon Cancer: A Population-Based Study.

649Background: It is reported that sidedness (right vs. left) and histology (mucinous vs. non-mucinous) of CC is predictive of survival. We investigated whether the prognostic values of sidedness and histology were affected by each other. Methods: We identified 81342 patients with stage II–IV CC between 2004 and 2012 from the Surveillance, Epidemiology, and End Results database. Inverse probability propensity score weighting was used to balance the clinical features (i.e., age, sex, race, marital status, year of diagnosis, registry, tumor grade, and T and N stage) between the non-mucinous right-sided, non-mucinous left-sided, mucinous right-sided, and mucinous left-sided subgroups with stratification for tumor stage. Afterwards, overall survival (OS) was compared between these subgroups using univariable Cox proportional hazards models. Results: In stage III/IV CC, the prognosis for non-mucinous left-sided tumors was significantly better than that for non-mucinous right-sided tumors and that for mucinous ...