November 10, 2009

Topical Treatment Works Well for Anal Lesions

Trichloroacetic acid (TCA), a topical liquid sometimes used to treat genital warts, may also be useful as a therapy for anal intraepithelial neoplasia (AIN) in HIV-positive and HIV-negative people, according to a study published in the December issue of the Journal of Acquired Immune Deficiency Syndromes.

Anal lesions from human papillomavirus (HPV) infection are a precursor to anal cancer. They are remarkably common in men who have sex with men (MSM), especially HIV-positive MSM. This is of particular concern, as anal cancer rates among HIV-positive people are on the rise.

Unfortunately, few options are available to treat pre-cancerous anal lesions. The most common method is cauterization—using electrical pulses to burn lesions away—or surgery, which can cause discomfort and complications.

To determine whether TCA, considered to be less invasive than cauterization or surgery, would work well on anal lesions, Jasmeet Chadha Singh, MD, from the St. Luke’s Roosevelt Hospital Center in New York City and her colleagues conducted a study involving 35 HIV-positive and 19 HIV-negative MSM.

Most of the men had moderate-to-severe lesions (AIN grade 2 or 3), as opposed to mild lesions (AIN grade 1) or anal warts exclusively.

An 85 percent concentration of TCA was applied to the lesions with a cotton swab. Researchers treated participants’ lesions with TCA four times, with intervals of about one to two months between treatments. TCA therapy was considered a success if it cleared all of the AIN lesions by the fourth treatment.

Singh’s group found that TCA was successful in 32 percent of those with AIN 2 or 3 lesions. In 29 percent, AIN 2 or 3 lesions were reduced in severity to AIN 1.

TCA was somewhat less effective in HIV-positive MSM, with 34 percent completely clearing the lesions, compared with 47 percent of HIV-negative MSM. Men 48 years old and younger were also more likely than men 49 and older to completely clear the lesions.

Unfortunately, recurrence of the lesions—which is common regardless of the treatment used—occurred in up to 75 percent of those who’d had complete resolution of their lesions within six months of finishing treatment.

TCA was safe and well tolerated, with only 5 percent of the participants complaining of mild discomfort or a flare of psoriasis.

The authors point out one major shortcoming of the study—that TCA was not compared head-to-head with other treatments commonly used to manage AIN, and they recommend that such clinical trials be conducted. They also acknowledge that treatment of anal lesions has not been clearly proved to reduce the rates of anal cancer in the same way that treatment of cervical lesions prevents cervical cancer but that many providers recommend it nevertheless.

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Luis Portal, San Salvador, 2009-11-11 12:37:34
The United Nations Development Fund will be funding studies on AIDS in El Salvador.Do you know about a partner to work with in Central America.