IGF-IR in patients with advanced colorectal cancer in correlation with certain clinico-morphological factors: Initial report.

The insulin-like growth factor (IGF) system comprises two types of peptides (IGF-I and IGF-II), two types of receptors (IGF-IR and IGF-IIR) and six IGF-binding proteins (BP). This system is mainly responsible for the growth and division of cells in the body, regulation of the cell cycle and prevention of apoptosis. The expression of IGF-IR was assessed in the cells of resected primary colorectal tumours in 88 patients (age, 36-87 years; mean 64.78; males, 48 and females, 40) treated surgically at the Second Department of General and Gastroenterological Surgery, Medical University of Bialystok, Poland, in relation to various clinico-morphological factors. The post-operative material was analysed to find the histological type, location of lesions, lymph node involvement staging, distant metastases (pTNM classification), staging in Dukes' classification and the histopathological differentiation grade. The expression of IGF-IR in colorectal cancer cells was assessed using an immunohistochemical method. The findings were subjected to statistical analysis (Chi-square test, multivariation test and Mann-Whitney U test). A positive IGF-IR expression (in at least 10% of cancer cells) was observed in 44 patients. The mean immunoreactive cell count for IGF-IR in all of the tumours studied was 30.79%. The current study showed no correlation of IGF-IR expression in colorectal cancer cells with characteristics such as age and gender of patients, tumour location, type, histological differentiation or histopathological advancement. Immunohistological determination of IGF-IR expression in advanced colorectal cancer cells revealed controversial scores. Evaluation should be confirmed by using other methods and enhanced to include adenomas and early colorectal cancers.