Abstract: Abstract Embryological, physiological and biochemical data suggest that proximal and distal(right-orleft-sided) parts of the colon in relation to the splenic flexure represent distinct functional entities. Recent advances in epidemiology and tumorigenesis of colon cancer have elucidated profoundly the bases upon which lie the differences in clinical presentations, responses to therapy and prognosis between those two cancers. Classification of colonic carcinomas in conjunction with anatomical location,clinicopathology and molecular signature will guide tailored prevention and therapy.