Expectant Management of High-Grade Anal Dysplasia in People with HIV: Long-term Data

BACKGROUND: Both ablation and expectant management of high-grade squamous intraepithelial lesions have been proposed. Expectant management would be reasonable if 1) the rate of high-grade squamous epithelial lesion progression to anal squamous cell carcinoma were low, and 2) anal squamous cell carcinoma arising under surveillance had a better prognosis than anal squamous cell carcinoma presenting without an identified precursor. OBJECTIVE: This study aims to quantify aspects of high-grade squamous epithelial lesion/anal squamous cell carcinoma clinical evolution in a surgical practice. DESIGN: This is a retrospective cohort study. SETTINGS: This study was performed in 1 colorectal surgeon's practice over a 20-year period. PATIENTS: Consecutive patients with high-grade squamous intraepithelial lesion and anal squamous cell carcinoma were included. MAIN OUTCOME MEASURES: We looked at the rate and timing of progression to anal squamous cell carcinoma, and the stage, treatment, and outcome of anal squamous cell carcinoma. We reviewed a comparison group of HIV-positive patients presenting de novo with anal squamous cell carcinoma (no prior history of high-grade squamous intraepithelial lesion). RESULTS: With consideration of only HIV-positive patients, 341 patients had a mean 5.6 years follow-up from high-grade squamous intraepithelial lesion diagnosis to the most recent documented anal examination. Twenty-four of these surveillance patients developed anal squamous cell carcinoma, yielding a progression rate of 1.3% per patient-year. Mean follow-up was 7.3 years from the initial cancer diagnosis to the most recent contact. Forty-seven patients who presented de novo with anal squamous cell carcinoma developed 74 lesions, with a mean follow-up of 5.7 years after initial diagnosis. This de novo group had higher anal squamous cell carcinoma-specific mortality (3% per patient-year vs 0.05%). Our study did not show a significantly higher rate of high stage (stage III or IV) at anal squamous cell carcinoma diagnosis in the de novo group in comparison with the surveillance group (25.5% vs 8.3% (p = 0.09)). LIMITATIONS: This study was retrospective in nature and had a predominately male population. CONCLUSIONS: The progression of untreated high-grade squamous intraepithelial lesion to anal squamous cell carcinoma approximates 1% per patient-year. Anal squamous cell carcinoma developing under surveillance tends to be of an earlier stage and to require fewer major interventions than anal squamous cell carcinoma presenting de novo. Cancer-specific mortality was lower for malignancies that developed under surveillance. We suggest that expectant management of patients with high-grade squamous intraepithelial lesion is a rational strategy for preventing anal cancer morbidity. See Video Abstract at http://links.lww.com/DCR/A699.