Treatment of HIV-associated invasive anal cancer with combined chemoradiation

Abstract

There is an increased frequency of invasive anal cancer in HIV-seropositive men. Early treatment strategies in this patient group employed reduced dosages of chemotherapy or radiotherapy alone to reduce toxicity. Since 1989 we have used combined modality treatment consisting of chemotherapy 5-fluorouracil (5-FU) and mitomycin C, and concomitant radical radiotherapy to the pelvis (38-51 Gy in 20-30 fractions), with most patients receiving a perineal boost (10-18 Gy). 12 homosexual HIV-positive men have been treated. The median CD4 count at diagnosis of anal cancer was 209 cells/microl (range: 29-380 cells/microl), 5 had prior AIDS defining diagnoses. No patients had metastatic disease. Complete remissions were obtained in 9/11 evaluable patients and in 1 further patient following surgery. 2 patients relapsed both within 6 months of diagnosis. At a median follow-up of 4.8 years (range: 0.4-10 years), 4 patients have died (2 from anal cancer, 1 from treatment-related consequences and 1 from opportunistic infection in remission). Actuarial 2-year survival is 60% (95% confidence interval (CI): 29-91%). Grade 3 haematological toxicity was recorded in 3 patients, grade 4 and 5 gastrointestinal toxicity in 1 patient each and grade 3 skin toxicity in 1 patient. Radical chemoradiation may be given safely at conventional doses in HIV-positive patients, with a high complete response rate.