WASHINGTON — Intralesional bleomycin should continue to be a therapeutic option for treating plantar warts, Dr. William Stebbins said in a poster presentation at the annual meeting of the American Academy of Dermatology.
The efficacy of the antineoplastic agent bleomycin against recalcitrant plantar warts comes from its ability to bind to human papillomavirus DNA, resulting in single-strand breaks, direct cytotoxic effects, virucidal effects, and upregulation of tumor necrosis factor-α (J. Exp. Med. 1989;170:655–63).
Bleomycin is associated with injection pain and rare systemic events, so it is less commonly used for wart treatment than are other methods such as cryosurgery, laser treatment, or immunotherapy. But intralesional bleomycin can be effective in patients with especially large plantar warts that are resistant to other therapies, or for patients who want resolution of their warts in weeks rather than months.
In one of the few studies of intralesional bleomycin to include patient satisfaction as an outcome measure, Dr. Stebbins, a first-year dermatology resident at Mount Sinai Hospital, New York, and his associates reviewed 33 patients with one or more plantar or periungual warts who had received their last bleomycin injection at least 12 months prior to the study. Data were gathered from chart reviews and telephone interviews. The patients were 18 men and 15 women with a mean age of 39 years and a total of 257 treated warts.
Two-thirds of the patients had multiple warts, and most had attempted one or more other treatments unsuccessfully before undergoing the bleomycin injection. However, five of the patients, with 40 warts, were treatment naive, he noted.
Before the administration of bleomycin, the surgical site was anesthetized with lidocaine plus epinephrine using a 30-gauge needle. The wart was then pared down using a No. 15 scalpel blade. Bleomycin sulfate 3 U/cc was injected into the warty focus at a depth of 1–1.5 mm, using no more than 0.025–0.05 mL/3 mm2.
Treatment sessions were typically limited to a total dose of less than 3 U (or 1 mL) of bleomycin per area treated. Lower doses were delivered to the tips of the fingers or toes; slightly higher doses were used for large plantar lesions. The maximum total dose of bleomycin used in any one session was restricted to 5 U. Treated sites were covered with soft gauze, and a hemorrhagic callous was removed 2.5–3 weeks later.
This method resulted in complete resolution of all warts in 27 of the 33 patients: 16 of them after just one session and 22 after two sessions. All five treatment-naive patients experienced complete resolution, said Dr. Stebbins, who has no financial relationship with Bristol-Myers Squibb, manufacturer of bleomycin. Three-fourths of the patients reported a pain duration of less than 2 days, with one-third saying that their pain lasted less than 6 hours following the treatment, but five patients reported pain lasting more than 5 days. The average pain rating—including during and after the procedure—was 5.2 out of 10.
Other side effects included skin discoloration in one patient; callous formation in two patients; and pain, erythema, ulceration, and infection in one patient. There were no systemic or vascular side effects. In all, 26 of the 27 cured patients were satisfied with their treatment. One said it was too painful.