Surgical treatment of high-grade anal squamous intraepithelial lesions: a prospective study

The prevalence of anal squamous intraepithelial lesions is high among human immunodeficiency virus-positive homosexual males and, to a lesser extent, among human immunodeficiency virus-negative homosexual males. Furthermore, the incidence of high-grade squamous intraepithelial lesions, the putative precursor lesion to invasive cancer, is also high. We report the first prospective study of high-resolution anoscopy-directed surgical treatment of high-grade squamous intraepithelial lesions.

A prospective study of patients undergoing surgical treatment of high-grade squamous intraepithelial lesions (excision/cauterization of lesions visualized with high-resolution anoscopy) was performed. Follow-up anoscopy with biopsy and Papanicolaou smear was performed every three to six months.

Patients diagnosed with high-grade squamous intraepithelial lesions during the course of their participation in a prospective cohort study of anal squamous intraepithelial lesions were identified. From this group, 37 patients who were treated surgically between 1995 and 1999 were studied. Of these, 29 had tested positive for human immunodeficiency virus and 8 were negative for the virus. Mean patient age was 45 +/- 8 years. Mean duration of follow-up was 32.3 +/- 20.6 months in the human immunodeficiency virus-negative group and 28.6 +/- 12.9 months in the human immunodeficiency virus-positive group. No human immunodeficiency virus-negative patient developed recurrent high-grade squamous intraepithelial lesions. Twenty-three of 29 human immunodeficiency virus-positive patients had persistent or recurrent high-grade squamous intraepithelial lesions (P = 0.003; mean time to recurrence, 12 months). Six patients underwent reoperation for high-grade squamous intraepithelial lesions (4 recurred by 6 months). No patients developed incontinence, stenosis, postoperative infection, or significant bleeding after surgical treatment.

Surgical intervention directed by high-resolution anoscopy is safe and eliminates high-grade squamous intraepithelial lesions in human immunodeficiency virus-negative patients. The high persistence or recurrence rate in human immunodeficiency virus-positive patients suggests that multiple staged procedures and continued surveillance may be necessary.