Clinicopathological and prognostic significance of androgen receptor overexpression in colorectal cancer. Experience from Al-Madinah Al-Munawarah, Saudi Arabia.

Objectives: To examine the androgen receptor (AR) status in colorectal cancer (CRC) patients by the immunohistochemical method and to correlate the findings with all available clinicopathological parameters of prognostic significance.

Methods: Archival tumor samples were studied using immunohistochemistry for AR expression in 324 patients with CRC. Patients were diagnosed at the Pathology Department at a tertiary care Hospital, Al-Madinah Al-Munawarah, Saudi Arabia, between January 2006 and December 2017.

Results: There is a complete lack of AR expression in normal colonic mucosa; however, AR was expressed in 16 cases (40%) of colorectal adenoma. In CRC, AR expression was high in 118 cases (36.4%). There were no significant correlations between AR expression and gender, age, tumor histologic type, and tumor location. However, AR expression revealed a significant correlation with tumor size (p=0.026), tumor differentiation (p=0.047), American Joint Committee on Cancer (AJCC)  staging (p=0.043), lymph node positivity (p=0.018), lymphovascular invasion (p=0.018), and distant metastasis (p=0.049). In univariate Kaplan-Meier survival analysis, there was a significant (p=0.002) difference in overall survival between AR positive and negative tumors in favor of the latter. In multivariate (COX) models, high AR expression (p=0.002), AJCC (p less than 0.001), and lymphovascular invasion (p less than 0.001) were the only significant independent prognostic indicators of overall survival in CRC.Conlusion: Our study showed that the patients with higher AR expression had a significantly poorer survival rate, AR expression had the potential to be a prognostic marker of CRC.