Are there HIV-specific Differences for Anal Cancer Patients Treated with Standard Chemoradiotherapy in the Era of Combined Antiretroviral Therapy?

AIMS

Contradicting evidence exists regarding the safety and clinical outcome of standard treatment in HIV-positive patients with anal cancer. We report on our large, single-centre experience in HIV-positive versus HIV-negative patients treated in the era of combined antiretroviral therapy (CART).

MATERIALS AND METHODS

Between 1997 and 2015, 142 patients (42 HIV-positive versus 100 HIV-negative) with anal cancer were treated with standard chemoradiotherapy. Patients received a median dose of 50.4 Gy to the planning target volume; 91 (64%) patients received an external boost to the primary tumour and/or enlarged lymph nodes of 5.4-10.8 Gy. Concurrent chemotherapy was scheduled in the first and fifth weeks of radiotherapy using 5-fluorouracil and mitomycin C. The median follow-up was 51 (range 0-325) months.

RESULTS

HIV-positive patients were predominantly male (P<0.001), younger (P<0.001) and had more advanced nodal disease (P=0.042). A dose reduction of chemotherapy was necessary in 38% of HIV-positive patients and in 24% of HIV-negative patients (P=0.39). There was no significant difference in total dose or duration of radiotherapy (median 43 versus 44 days, P=0.59). Complete response (81% versus 87%, P=0.088), 5 year rates of local failure (26.2% versus 14.9%, P=0.176), 5 year rates of distant failure (14.3% versus 8.4%, P=0.371) and 5 year overall survival (70.7% versus 78.4%, P=0.491) were not significantly different. HIV-positive patients had worse 5 year cancer-specific survival (80.5% versus 93.8%, P=0.029) in univariate but not in multivariate analysis (P=0.276).

CONCLUSIONS

In the CART era, tolerance and clinical outcome are similar between HIV-positive and HIV-negative patients with anal cancer after standard chemoradiotherapy.