September 17, 2009
A new study finds that HIV-positive patients have a higher prevalence of colonic neoplasms and should be offered screening colonoscopy.
"Although non-AIDS defining malignancies are rapidly increasing as HIV-infected subjects live longer, little is known about the results of screening for colonic neoplasms (adenomatous polyps and adenocarcinomas) in this population," the authors wrote.
In the current study, the researchers evaluated the presence of colonic neoplasms in two groups: 136 asymptomatic HIV-infected persons age 50 or older, and 272 asymptomatic uninfected control subjects matched for age, sex, and family history of colorectal cancer.
The results showed the prevalence of neoplastic lesions detected by colonoscopy was significantly higher among patients with HIV (62.5 percent) than among HIV-negative patients (41.2 percent). This association persisted after adjustment for age, sex, race/ethnicity and baseline characteristics.
Compared to controls, HIV-positive patients were significantly less likely to have hyperplastic polyps and more likely to have adenomas 6-9 mm in diameter, and to have two or more adenomas detected.
Eleven patients had adenocarcinoma. Among these, patients with HIV were significantly younger (mean age 52.4) than controls (mean age 60.3). Patients with HIV were more likely to have advanced cancers (stage III or IV) than controls (60.0 percent vs. 16.7 percent, p=0.24). Multivariate analysis showed the odds of an HIV-positive patient having a neoplastic lesion were higher with a positive family history (odds ratio, 3.77) and lower among patients on highly active antiretroviral therapy (OR, 0.13). Duration of HIV infection, viral load and CD4 lymphocyte count were not associated with the presence of neoplastic lesions.
"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," the authors concluded. "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."
The report, "Screening Colonoscopy for the Detection of Neoplastic Lesions in Asymptomatic HIV-Infected Subjects," was published in Gut (2009;58:1129-1134).