Colon cancer, a single entity? Considerations about laterality in a Colombian oncology institution 2001-2016/Cancer de colon ?una sola entidad? Consideraciones sobre lateralidad en una institucion oncologica colombiana 2001-2016

Introduction: it has been suggested that cancers on the right and left sides of the colon are presented as different entities and as such should be addressed for study, treatment and follow-up. The purpose of this research is to make an analysis of patients with colon cancer according to laterality. Materials and methods: a retrospective cohort of 442 patients referred to Oncologos del Occidente from January 2001 to December 2016 with a diagnosis of colon cancer. Results: 54% of the cases were in the left colon; 52% female sex; average age: 60.5 years on the left and 62.5 on the right; mucinous histology (40% vs 60%), signet ring cells (40% vs 60%) and poorly differentiated (40% vs 60%); mean carcino-embryonic antigen 51.7 vs 63.9 ng/mL; resected lymph nodes greater than or equal to 13 (41% vs 59%); presence of obstruction (22% vs 18%), serosa involvement (16% vs 18%) and ulceration (21% vs 17%). There was relapse in 58% vs 42% and of them to liver (33% vs 23%), lung (18% vs 15%) and carcinomatosis (15% vs 14%). The mean global follow-up was 40.1 [+ or -] 39 with 38.3 months for the left side and 42.2 months for the right, and survival at 5 years of 61% vs 64% for the left and right colon, respectively. Conclusion: the pattern of occurrence of colon cancer according to its laterality is presented on the right side in smaller numbers, older age, more aggressive histology, higher nodal level, greater serosal involvement, longer follow-up and similar survival. The above, added to the mutational state, could help to define the initial therapeutic management. There are still many doubts to understand the difference in results not explained only based on laterality.Keywords: Colon cancer; Laterality; Epidemiology; Treatment; Survival.Introduccion: ha sido sugerido que los canceres del lado derecho e izquierdo del colon se presentan como entidades diferentes y como tal deberian ser abordados para su estudio, tratamiento y seguimiento. El proposito de esta investigacion es hacer un analisis de pacientes con cancer de colon segun la lateralidad. Materiales y metodos: cohorte retrospectiva de 442 pacientes remitidos a Oncologos del Occidente desde enero de 2001 a diciembre de 2016 con diagnostico de cancer de colon. Resultados: el 54 % de los casos fueron en colon izquierdo; sexo femenino 52 %; media de edad: 60,5 anos en izquierdo y 62,5 en derecho; histologia mucinosa (40 % vs 60 %), celulas en anillo de sello (40 % vs 60 %) y mal diferenciado (40 % vs 60 %); medi