Clinical, anatomopathological and molecular characteristics of colorectal cancer by tumor location and degree of differentiation

Aims: Colorectal cancer (CRC) has a high incidence and mortality, with different patterns depending on anatomical location and other pathological characteristics that appear linked to changes in exposure risk factors exposure as well as the diagnosis. All these make it essential to determine the source of the tumour to properly assess the effect of these factors in the development, diagnosis and progression of the disease. The aim was to describe the clinical and anatomical -pathological characteristics of patients diagnosed with CRC in the Health Area of Leon (ASL) based on their location and degree of tumour differentiation. Methods: Information was collected on the clinical and pathological characteristics, including biological markers analysed in clinical routine of 408 patients between 25 and 85 years with a confirmed diagnosis of CRC, and residents in ASL at least six months before diagnosis. Univariate and bivariate analyses were performed according to the degree of differentiation and tumour location. Results: Tumour size decreases from the colon to the rectum from location decline proximal colon to the rectum (Proximal Colon = 5.13 cm; Distal Colon = 4.09 cm; Rectum = 3.17 cm, P < 0.001), with the TNM stage also being higher in proximal areas. Mucinous adenocarcinomas are more frequent in poorly differentiated than in well differentiated tumours (23.1% vs 5.5%). Lymphatic, venous and peri-tumour invasions are more common in poorly differentiated tumours. Conclusions: The distribution in accordance with the location has more advanced TNM stages in the proximal areas, which could be related to the poorer early diagnosis in proximal areas. The association between venous and lymphatic invasion with the degree of differentiation is poorly understood, and requires studies to clarify their possible prognostic interest. (C) 2014 Institute Nacional de Cancerologia. Published by Elsevier Espana, S.L.U. All rights reserved.