A Single Center Pilot Study Accessing Subject Tolerability and Quality Of Life After Circumferential Anal Canal Radiofrequency Ablation of High-Grade Dysplasia

Background: HIV-positive (HIV+) subjects are at high risk for anal high-grade squamous intraepithelial lesions (HSIL), which can progress to cancer. Most dysplasia occurs at the squamocolumnar junction (SCJ). Radiofrequency ablation (RFA) effectively treats SCJ esophageal and anal dysplasia to hopefully decrease progression to cancer. Circumferential esophageal SCJ ablation is safe and well tolerated. We endeavored to determine if this was true in the anus.

Methods: A prospective trial investigated safety and tolerability of circumferential anal RFA using Barrx^TM 60 RFA focal catheters (Medtronic, Sunnyvale CA) in subjects with ≥1 anal SCJ HSIL. The entire SCJ was ablated to treat baseline and occult HSIL(s). Subject symptoms and quality of life were assessed with non-validated surveys prior to ablation, for 28 days post-ablation, and at 3, 6, 9, and 12 months post-ablation. Subjects reported their experiences on a visual scale ranging from 0 to 10 (0 no experience, 10 greatest severity).

Results: Ten males (9 HIV+) enrolled. Median post-ablation anal pain was 5 (range 2-9) but resolved to a minimal level (0 or 1) within a median of 20 (0-29) days. During the first week after RFA, seven subjects experienced mild or moderate anal bleeding, not requiring any intervention. Median days to bleeding resolution was 1 (range 0-4) days. Seven subjects experienced mild or moderate incontinence (mucous or stool discharge) following treatment. One subject developed thin stool and straining to pass bowel movements at 3 months after significant diarrhea several weeks before. He had a soft, circumferential, mid canal scar that was easily dilated. All symptoms resolved. Narcotics usage for pain relief was minimal (N= 3 subjects) and median days of pain reliever usage was 13 (3-22) for non-narcotics and 8 (4-14) for narcotics. All subjects who tried receptive anal sex post-RFA succeeded, including the subject with the dilated stricture. Median subject score for worry about anal canal condition was 4.5 (range 0-8) falling to 0.5 (range 0-5) 9 to 12 months post-RFA.

Conclusion: Circumferential RFA of anal canal HSIL in HIV+ subjects was well-tolerated with easily controlled pain, minimal bleeding and minimal adverse events.