Infrared coagulator: a useful tool for treating anal squamous intraepithelial lesions

The incidence of invasive anal squamous carcinoma in men who have sex with men is rising, particularly in those with human immunodeficiency virus. As in the cervix the high-grade squamous intraepithelial lesion is thought to be an invasive squamous cell carcinoma precursor. Cervical high-grade squamous intraepithelial lesions are treated by removing the squamocolumnar transition zone. This is not possible in the anus, where treatment is often surgical and is accompanied by significant pain and morbidity. Better office-based techniques to treat anal high-grade squamous intraepithelial lesions are needed. We employed the infrared coagulator in an office setting to ablate high-grade squamous intraepithelial lesions.

A retrospective review of medical records was performed on 68 human immunodeficiency virus-positive men who have sex with men who underwent infrared coagulator ablation of biopsy-proven high-grade dysplasia from the time we began using the procedure in 1999. All patients have had at least six months of follow-up. Procedures were performed with local anesthesia on patients with discrete high-grade squamous intraepithelial lesions. Follow-up consisted of anal cytology with high-resolution anoscopy and biopsy of suspicious areas every three to six months. New or recurrent high-grade dysplasia was retreated. Patients with circumferential or bulky disease were treated in the operating room and were excluded from the study.

Altogether, 68 patients met the enrollment criteria. The median patient age was 41 years (range 29-62 years). A total of 165 lesions were treated (mean 1.6 lesions, range 1-5) and only 46 (28 percent) persisted. However, 44 patients (65 percent) developed a new or persistent high-grade squamous intraepithelial lesion within a median time of 217 days (range 27-566 days) after infrared coagulation. The remaining 24 patients (35 percent) were free of high-grade dysplasia for a median of 413 days (range 162-1313 days) after infrared coagulation. When patients were treated a second or third time, the incidence of new or persistent high-grade dysplasia dropped to 58 percent and 40 percent, respectively. The probability of curing a retreated lesion was 72 percent. Using generalized estimating equations, the incidence of high-grade dysplasia decreased with repeated infrared coagulator treatments. No patient developed squamous-cell carcinoma, had a serious adverse event, or developed anal stenosis.

The infrared coagulator is a safe, office-based modality for treating anal high-grade squamous intraepithelial lesion in human immunodeficiency virus-positive men who have sex with men. Successive treatments led to decreased recurrence rates.