Background: Data on colorectal cancer (CRC) in HIV-positive patients are limited. The study objective was to investigate and compare clinical presentation and outcome between HIV-positive and HIV-negative CRC patients. Patients and Methods: Between September 1985 and November 2003 we identified 27 cases of HIV-positive CRC patients from the cancer registry database-Italian Cooperative Group AIDS and Tumours (GICAT); the clinical presentation/outcome information was retrieved. Each HIV-positive patient from our institution was randomly matched (ratio 1: 2) with HIV-negative patients (54 controls) based on age, sex, and year of diagnosis in the same time period. Differences in clinical presentation, treatment, and overall survival were assessed. Results: Of 1130 HIV-negative CRC patients, 54 were identified and matched with 27 HIV-positive patients. Compared with the HIV-negative patients, the HIV-positive patients had a higher risk of lower performance status (PS: >= 2) (odds ratio (OR) = 14.4; 95% confidence interval (CI): 3.6-57.7), a higher risk of unfavorable Dukes' stage (D) (OR = 4.9; 95% CI: 1.8-13.5), and a higher risk of poor grading (G3-G4) (OR = 5.0; 95% CI: 1.9-13.4). Median overall follow-up was 27 months (range: 2-212). At multivariate analysis, the only characteristics that significantly reduced the survival of the CRC patients were: HIV-positive status (hazard ratio (HR): 2.4; 95% CI: 1.1-5.2) and Dukes' stage D (HR: 3.7; 95% CI: 1.9-7.1). Conclusion: Our data show that HIV-positive CRC patients compared to HIV-negative patients have a poorer PS, an unfavorable Dukes' stage, higher grading and shorter survival.
