(P095) Comparison of Toxicity and Treatment Outcomes in HIV-Positive Versus HIV-Negative Patients With Squamous Cell Carcinoma of the Anal Canal

Evan C. White, MD, Behnood Khodayari, BS, Kelly T. Erickson, MD, Julie Hwang-Graziano, MD, Winston Lien, MD, Aroor Rao, MD; Kaiser Permanente Southern California, Los Angeles Medical Center

Purpose: To compare toxicity and treatment outcomes in human immunodeficiency virus (HIV)-positive vs HIV-negative patients with squamous cell carcinoma of the anal canal who underwent definitive concurrent chemoradiation at a single institution.

Materials and Methods: A total of 53 consecutive HIV-positive patients treated between 1987 and 2007 were compared with 205 consecutive HIV-negative patients treated between 2003 and 2007. All patients received radiotherapy at a single regional facility. Median radiation dose was 54 Gy (range: 28–60 Gy). Concurrent chemotherapy consisted of 2 cycles of 5-fluorouracil (5-FU) (1,000 mg/m²/day on Days 1–4 and 29–32), along with mitomycin C (10 mg/m²) given on Day 1 +/− Day 29). After treatment, patients were closely followed with imaging studies, clinical examinations, and rigid proctoscopies. Outcomes assessed were toxicity rates, progression-free survival (PFS), colostomy-free survival (CFS), cancer-specific survival (CSS), and overall survival (OS).

Results: Median follow-up was 34 months. Compared with HIV-negative patients, HIV-positive patients were younger (median age: 48 yr vs 62 yr) and predominantly male (98% of HIV-positive patients were male vs 22% of HIV-negative patients). Also, 37 (70%) HIV-positive patients were on highly active antiretroviral therapy (HAART), and 26 (65%) had an undetectable viral load at the time of treatment; 36 (72%) had a CD4 count > 200 (mean CD4 count: 455). There were no significant differences in acute or late nonhematologic or hematologic toxicity rates between the two groups. At 3 years, there was no significant difference between HIV-positive and HIV-negative patients in regard to PFS (75% vs 76%), CFS (85% vs 85%), or CSS (79% vs 88%; P = .36), respectively. On univariate analysis, there was a trend toward worse OS in HIV-positive patients (72% vs 84% at 3 yr; P = .06). On multivariate analysis, only male gender and stage were predictive of worse survival outcomes. HIV status was not associated with worse outcomes in Cox models.

Conclusions: In the HAART era, HIV-positive patients with anal cancer can undergo standard definitive chemoradiation and expect equivalent toxicity and survival outcomes compared with HIV-negative patients.