Combined Modality Therapy for Patients With With HIV and Stage I, Stage II, or Stage III Anal Cancer

OBJECTIVES: Primary * Determine the 2-year local failure rate in patients with HIV-associated stage I-IIIB anal carcinoma treated with cisplatin, fluorouracil, cetuximab, and radiotherapy. * Determine the objective response rate (complete and partial), progression-free survival, relapse-free survival, colostomy-free survival, overall survival, quality of life, and overall toxicity in patients treated with this regimen. Secondary * Characterize the effect of this regimen on the underlying HIV condition by describing changes in viral load, CD4 counts, and the incidence of opportunistic illnesses, including the development of AIDS during and in the first year after treatment. * Evaluate the effect of this regimen on anogenital human papilloma virus (HPV) infection and anal cytology. OUTLINE: This is an open-label, multicenter study. Patients receive cetuximab IV over 1-2 hours on days 1, 8, 15, 22, 29, and 35\*, fluorouracil IV continuously on days 1-4 and 29-32, and cisplatin IV over 1 hour on days 1 and 29. Beginning on day 1, patients undergo concurrent radiotherapy to the primary tumor 5 days a week for 5-7 weeks. Treatment continues in the absence of disease progression or unacceptable toxicity. NOTE: \*Patients receiving 7 weeks of radiotherapy also receive cetuximab on days 42 and 49. Quality of life is assessed at baseline, at the completion of study treatment, and then at months 3, 6, 12, 24, and 36. After completion of study treatment, patients are followed periodically for 5 years. PROJECTED ACCRUAL: A total of 47 patients will be accrued for this study.