Background: Although non-AIDS defining malignancies are rapidly increasing as HIV-infected subjects live longer, little is know about the results of screening for colonic neoplasms (adenomatous polyps and adenocarcinomas) in this population.
Methods: We conducted a screening colonoscopy study to determine the prevalence of colonic neoplasms in 136 asymptomatic HIV-infected subjects ≥50 years of age and 272 asymptomatic uninfected control subjects matched for age, sex, and family history of colorectal cancer. Advanced neoplasms were defined as adenomas ≥10mm or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or adenocarcinoma.
Results: The prevalence of neoplastic lesions was significantly higher in HIV-infected subjects than in control subjects (62.5% vs. 41.2%, P <0.001), and remained highly significant after adjustment for potential confounding variables (odds ratio = 3.00; 95% confidence interval, 1.83 - 4.93). Among patients with colorectal adenocarcinoma, HIV-infected subjects were significantly younger (52.4 ± 1.3 vs. 60.3 ± 4.0 years, P = 0.002) and were more likely to have advanced cancers (stage III or IV) than control subjects (60.0% vs. 16.7%, P = 0.24). Of HIV-infected subjects with advanced neoplasms proximal to the splenic flexure, distal neoplastic lesions were absent in 88.9% of individuals and these would have been missed by flexible sigmoidoscopy.
Conclusions: HIV-infected subjects have a higher prevalence of colonic neoplasms, and adenocarcinomas develop at a younger age and are more advanced than in uninfected subjects. Our findings suggest that screening colonoscopy should be offered to HIV-infected subjects, but the age of initiation and the optimal frequency of screening require further study.