Invasive anal squamous-cell carcinoma in the HIV-positive patient: outcome in the era of highly active antiretroviral therapy.

Introduction: The incidence of invasive anal squamous-cell carcinoma in patients with HIV is increasing. We report the outcome after combined chemoradiotherapy for anal squamous-cell carcinoma in HIV-infected individuals.

Methods: Thirty-two HIV-positive patients treated at the St. Vincent's Cancer Care Center for anal squamous-cell carcinoma from 1997 through mid 2005 were reviewed retrospectively. All patients also received highly active antiretroviral therapy. Treatment consisted of radiotherapy concurrent with 5-fluorouracil and mitomycin C in most patients. Overall survival, anal cancer-specific survival, local recurrence, and toxicity were assessed.

Results: Median time from completion of radiotherapy to last follow-up of surviving patients was 35 months. Five-year locoregional relapse, anal cancer-specific survival, and overall survival were 16 , 75, and 65 percent, respectively. In multivariate analysis, locoregional recurrence, cancer-specific survival, and overall survival were all significantly associated with tumor size. Overall survival was independently associated with high viral load and low CD4 count. Acute toxicity included: Grade 3 skin in 25 percent of patients, Grade 3 diarrhea: 28 percent, and Grade 3 or 4 hematologic toxicity in 21 and 48 percent, respectively. More than two-thirds of patients required radiotherapy interruption. There was no negative impact of chemoradiotherapy on viral load.

Conclusions: Outcome after chemoradiotherapy for HIV-related anal squamous-cell carcinoma in the era of highly active antiretroviral therapy is comparable to outcome in patients without HIV. However, significant toxicity is seen with standard treatment regimens. Earlier diagnosis and risk-adapted therapy could lead to improved survival and decreased treatment-related morbidity.