Infrared Coagulation in Preventing Anal Cancer in Patients With HIV Who Have Anal Neoplasia

DISEASE CHARACTERISTICS: * HIV positive * Presence of internal anal lesions with histologically confirmed high-grade squamous intraepithelial neoplasia with at least 1 positive margin * No more than 3 lesions, each no more than 10 mm in diameter * No evidence of microscopic invasion in any anal biopsy specimens * No history of anal cancer PATIENT CHARACTERISTICS: Age * Over 18 Performance status * Karnofsky 70-100% Life expectancy * Not specified Hematopoietic * Platelet count at least 50,000/mm\^3 * CD4 count at least 50 cells/mm\^3 Hepatic * Not specified Renal * Not specified Other * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No allergy to lidocaine * No anal insertions, including enemas or anal intercourse, for 24 hours before and at least 1 week after study treatment * No prior severe photosensitivity reaction * No active opportunistic infection * No concurrent neoplasia requiring cytotoxic therapy PRIOR CONCURRENT THERAPY: Biologic therapy * Not specified Chemotherapy * Not specified Endocrine therapy * Not specified Radiotherapy * Not specified Surgery * Not specified Other * Must be on stable regimen of highly active antiretroviral therapy (HAART) for at least 12 weeks prior to study entry unless CD4 count \> 200/mm\^3 AND no plans to initiate HAART within the next 3 months * More than 14 days since prior acute treatment for an infection or other medical illness * No prior inf…