[Clinicopathological characteristics of colorectal cancer complicated with type 2 diabetes mellitus: analysis of clinicopathological data from 3, 202 colorectal cancer patients].

Objective: the aim of this study was to determine the clinicopathological characteristics of colorectal cancer (CRC) patients complicated with type 2 diabetes mellitus (T2DM ).
Methods: A total of 3, 202 patients with CRC confirmed pathologically in Tianjin Union Medicine Center from January 2005 to December 2009 were included in this study. We analyzed the differences in clinicopathological features between T2DM patients and non-diabetic patients according to age of diagnosis, gender, tumor site, stage, gross type, histological type, and differentiation.
Results: From 2005 to 2009, the number of CRC patients increased yearly. The high incidence age of all CRC patients was 51 to 80 years old. The male to female ratio was 1.18:1, showing that the number of female patients with CRC was increased significantly compared with males. The CRC distribution of T2DM patients and non-diabetic patients showed a predominance of rectal cancer (64.4%, 68.7%), followed by sigmoid colon cancer (12.5%, 13.0%), and moderately differentiated ulcer-type adenocarcinoma. Compared with non-diabetic patients, T2DM patients were older (66.2 years versus 62.7 years, P < 0.001) and had more multiple CRCs (3.5% versus 1.6%, P < 0.001). Moreover, the proportion of lymph node or organ metastasis in T2DM patients was higher than that in non-diabetic patients (52.6% versus 45.6%, P < 0.05). No significant differences were observed between both groups in terms of gender, gross type, histological type, and differentiation(P > 0.05 for all).
Conclusions: CRC incidence shows an increasing trend with age. CRC patients with T2DM have an older age of onset, higher proportion of lymph node and distant organ metastasis than in non-diabetic patients.