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

DISEASE CHARACTERISTICS: * Histologically confirmed stage I-IIIB invasive anal canal or perianal (anal margin) squamous cell carcinoma, including tumors with any of the following nonkeratinizing histologies: * Basaloid * Transitional cell * Cloacogenic * Documented HIV infection by 1 of the following: * Antibody detection * Culture * Quantitative assay of plasma HIV RNA PATIENT CHARACTERISTICS: * Karnofsky performance status 60-100% * Absolute neutrophil count ≥ 1,500/mm³ * Platelet count ≥ 100,000/mm³ * Hemoglobin ≥ 10 g/dL (transfusions, epoetin alfa, or myeloid growth factor support allowed provided blood counts are stable for ≥ 2 weeks prior to study entry) * Creatinine ≤ 1.5 times upper limit of normal (ULN) OR creatinine clearance \> 60 mL/min * AST and ALT ≤ 3 times ULN * Bilirubin ≤ 2 times ULN * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No acute active, serious, uncontrolled opportunistic infection * No other prior invasive malignancy diagnosed within the past 24 months, excluding in situ cervical cancer, anal dysplasia or carcinoma in situ, nonmelanoma skin carcinoma, or Kaposi's sarcoma that has not required systemic chemotherapy within the past 24 months * No peripheral neuropathy \> grade 1 * No severe or poorly controlled diarrhea * No medical or psychiatric illness that would preclude study requirements PRIOR CONCURRENT THERAPY: * No prior chemotherapy or radiotherapy for this mali…