Increased Prevalence of Colorectal Carcinoma (CRC) in a HIV + Cohort: A Single-Center Retrospective Study

Abstract

Introduction: Improved life expectancy following the advent of anti-retroviral therapy (ART), has resulted in an increase in Non-AIDS Defining Cancers (NADCs) in patients with HIV. Published data are inconsistent on the prevalence of colorectal carcinoma (CRC) and outcomes of colon cancer screening in this cohort. Our aim was to evaluate the prevalence of colorectal neoplasms in HIV + patients undergoing screening colonoscopy and determine predictors of adenomas and CRC within this group. Methods: We performed a single-center retrospective cohort study of HIV + patients undergoing screening colonoscopy between 2012-2015. Known and hypothesized predictors of CRC and polyp characteristics were assessed (Table 1). Patients with a prior history of colon cancer or CRC screening, inflammatory bowel disease, inadequate or incomplete colonoscopy were excluded. Bivariate analyses were conducted to identify variables associated with colorectal neoplasms.Table 1: Patient Demographic and Clinical CharacteristicsResults: Our cohort of 168 patients had a mean age of 56.7 yrs (SD 5.2), was predominantly African American (86%) with 62% (104) men. 93% of patients were on ART and 45% had an undetectable HIV RNA. Baseline demographics are presented in Table 1. The prevalence of all adenomas was 27.4 % (46/168) and for advanced adenomas it was 6.6% (11/167). Colorectal cancer was detected in 3% of patients (5/167). CRC was detected in the sigmoid colon in 3, ascending colon in 1 and synchronous CRC in the ascending and sigmoid colon in 1 patient. Bivariate analysis of demographics and risk factors showed that CD4 count, history of ART, Hepatitis B or C status were not associated with adenoma amongst the HIV cohort. Age was significantly associated with CRC (p = 0.03) (Table 2). The mean age of patients with CRC was 61.8 years (SD: 5.9) years vs. 56.5 years (SD: 5.0) in patients without CRC.Table 2: Bivariate Analysis of Demographic/Clinical Predictors among HIV + Patients Undergoing Screening ColonoscopyConclusion: In our cohort, the overall prevalence of adenomas and advanced adenomas was comparable to the general population and above the thresholds for adenoma detection. Our cohort interestingly showed a notably higher rate of CRC (3%) compared to large, population-based screening colonoscopy studies (0.1-0.5%) and also other prior HIV cohorts, suggesting an increased risk in the HIV population during the ART era. This study reinforces the need for further research and refinement of colon cancer screening recommendations for individuals with HIV.