Efficacy of trichloroacetic acid in the treatment of anal intraepithelial neoplasia in HIV-positive and HIV-negative men who have sex with men.
BACKGROUND
Anal intraepithelial neoplasia (AIN), particularly AIN 3 is a precursor to anal cancer. Most cases of AIN are intraanal, but few treatments for intraanal AIN are currently available. Topical 85% trichloroacetic acid (TCA) is an inexpensive method used to treat perianal condyloma, a form of AIN 1, but its efficacy to treat intraanal AIN as first-line therapy is unknown.


METHODS
Retrospective review of medical records was performed for all patients with AIN treated at the University of California San Francisco Anal Neoplasia Clinic with TCA as the first-line therapy from January 2000 to December 2004. Clearance was defined as the absence of AIN confirmed by high-resolution anoscopy and cytology after up to 4 TCA treatments.


RESULTS
Thirty-five HIV-positive men and 19 HIV-negative men met the enrollment criteria. In multivariate analysis, greater clearance was seen in patients 41-48 years of age versus >49 years [odds ratio (OR): 8.4, confidence interval (CI): 1.1 to 94, P: 0.04]. Among HIV-positive men, those with 2 or fewer lesions showed greater clearance (OR: 14.3, CI: 1.5 to 662, P: 0.01). 32% of patients with AIN 2/3 cleared to no lesions. On a per lesion basis, 73% of AIN 1 and 71% AIN 2/3 cleared to no lesion or AIN 1 or less, respectively.


CONCLUSIONS
Topical 85% TCA was safe and well tolerated. It was more effective in younger patients and among HIV-positive patients, those with 2 or fewer lesions. A high proportion of AIN 2/3 lesions responded to TCA treatment.
Singh
Jasmeet Chadha
JC
Department of Internal Medicine, St. Luke's Roosevelt Hospital Center, USA.
Kuohung
Victoria
V
Palefsky
Joel M
JM
D000287:Administration, Topical; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001005:Anus Neoplasms / Q000150:complications / Q000188:drug therapy*; D002278:Carcinoma in Situ / Q000150:complications / Q000188:drug therapy*; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy*; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011230:Precancerous Conditions / Q000150:complications / Q000188:drug therapy*; D012189:Retrospective Studies; D014238:Trichloroacetic Acid / Q000008:administration & dosage / Q000627:therapeutic use*
D000970:Antineoplastic Agents; D014238:Trichloroacetic Acid