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

April 15, 2014
Oncology, Oncology Vol 28 No 1S, Volume 28, Issue 1S

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.

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.