Warts and molluscum contagiosum (MC) are common dermatologic conditions caused by viral infections and often affect pediatric patients. There are several treatment options available for both conditions; however, the benefits of treating these benign conditions have to be weighed against the pain and trauma, as well as other adverse effects, associated with the various treatment modalities.
According to Anthony J. Mancini, MD, FAAD, FAAP, chief of dermatology in the department of pediatrics at Ann & Robert H. Lurie Children’s Hospital of Chicago and professor of pediatrics and dermatology at Northwestern University Feinberg School of Medicine, the most important treatment consideration clinicians should make is to try to eradicate the lesions while minimizing pain and trauma. Dr Mancini presented on this topic at the 2020 Fall Clinical Dermatology Conference.1
“These lesions often resolve over time,” he said. In one study, 65% of warts were resolved after 2 years and 80% were resolved within 4 years.2 For MC lesions, one study that compared the resolution of MC with and without treatment showed treatment did not shorten the amount of time to resolution.3
While these lesions are benign, patients and parents may elect to undergo therapy for a variety of reasons. Selecting the best option should be based on patient factors (eg, age) and the risk/benefits of treating the lesions.
There are multiple modalities used to treat warts, including salicylic acid, cryotherapy, cantharidin, retinoids, phototherapy, surgery, cimetidine, antigen injections, imiquimod, interferon, topical immunotherapy, zinc sulfate, 5-fluorouracil (5-FU), bleomycin, cidofovir, podophvllin, hyperthermia/occlusive heat patch, cold atmospheric pressure plasma, duct tape, garlic, sinecatechins, hypnosis, and glutaraldehyde. In addition to active treatment, a “wait and see” approach is also appropriate, as these lesions often resolve on their own.1
Off-label use of oral cimetidine, administered for at least 8 to 12 weeks at 30 to 40 mg/kg/day, may boost the host immune response against the human papillomavirus, explained Dr Mancini. “When it is effective, it can be very helpful,” he said. Off-label use of 5% 5-FU cream can also be useful for resolving facial flat warts when applied from a few nights per week to nightly (as tolerated), he added. In addition, combination modalities using more than one of these approaches, such as oral cimetidine in conjunction with 5-FU cream, may also be helpful..
A compounded topical therapy, specifically designed for warts, includes 17% salicylic acid and 2% 5-FU cream in a sustained-release adhesive vehicle. It is applied nightly with clear plastic tape occlusion until the wart resolves. The advantages of this therapy, according to Dr Mancini, are that it is faster than over-the-counter salicylic acid, has a high efficacy, and is painless. It is not FDA-approved, and one barrier of this medication is that most insurance providers do not cover it, and the out-of-pocket cost is roughly $80.1
For more resistant warts, some options include intralesional injection of antigens, topical immunotherapy (Dr Mancini prefers squaric acid dibutylester) and topical cidofovir.
Similar to warts, MC has several treatment modalities for patients and parents interested in therapeutic options beyond the “wait and see” approach. These include topical cantharidin, trichloroacetic acid, podophyllin, silver nitrate, salicylic acid, benzol peroxide, hydrogen peroxide, potassium hydroxide, retinoids, cimetidine, interferon, cidofovir, Candida antigen, manual extraction, CO2 laser, pulse dye laser, essential oils/tea tree oil, tape, and hyperthermia. While Dr Mancini noted that imiquimod can be used off-label for treating MC, it should be done very cautiously as it has been reported in association with several serious adverse effects including erosive cheilitis, aphthous stomatitis and pemphigus-like eruptions.1
Cantharidin is considered to the “gold standard” for treating MC in pediatric patients because it is both effective and painless during the procedure, explained Dr Mancini. Patients may develop mild pain with blistering, but this “occurs at home, so younger patients do not relate this [pain] to the actual office application, which is painless and allows for repeat therapy as needed,” he said.
A new drug device (VP-102) is being reviewed by FDA, with approval pending in 2020. VP-102 is a novel drug device that contains 0.7% cantharidin, which includes a bitter agent to dissuade oral ingestion and has a purple color indicator. Two identical phase 3 studies (CAMP-1 and CAMP-2) investigated the efficacy of this therapy for achieving complete clearance of MC lesions on various areas of the body, including the head, groin, and neck, by end of the study period (day 84). Both studies showed treatment with VP-102 was superior to vehicle, with 46.3% and 54% of participants in CAMP-1 and CAMP-2, respectively, achieving complete clearance compared with 17.9% and 13.4% in the vehicle group. While adverse events were more common among those treated with VP-102 (99% and 95% vs 73% and 66%, respectively), the events were mild to moderate in severity and included site vesicles, pain, pruritus, erythema, and scab.4 Dr. Mancini pointed out that the strict primary endpoint of “complete clearance” of MC lesions makes these results even more impressive, as most clinicians expect to see new lesions develop in between treatment sessions (despite clearance of previously-treated lesions).
If approved, this would be the first FDA-approved treatment for MC, said Dr Mancini.
Both warts and MC are benign and generally self-limiting. However, there are a variety of reasons that therapy may be desirable, and if patients and parents wish to undergo treatment, “our treatment considerations should always incorporate the patient’s age, developmental level, and the risk-to-benefit ratio between treatment efficacy/indication and pain/trauma,” said Dr Mancini.
For treating MC and warts, “it is important that we remember to first do no harm,” he said. He has a “no hold policy” in his office. “With in-office cryotherapy, if the parents or I need to hold a flailing young child in order to apply liquid nitrogen to a wart, the procedure will typically not be performed,” he explained.
When caring for pediatric patients with benign skin conditions, “we should always consider how traumatic experiences in doctors’ offices can translate into long-term memories and negative reinforcement for children with regard to future office visits for any medical or dental care, making these visits more traumatic and less enjoyable for the patient, parent and clinician alike,” he added.
1. Mancini AJ. Warts and molluscum in children – approaches & pearls. Presented at: 2020 Fall Clinical Dermatology Conference; October 30, 2020; virtual.
2. Kuwabara AM, Rainer BM, Basdag H, Cohen BA. Children with warts: a retrospective study in an outpatient setting. Pediatr Dermatol. 2015;32(5):679-683. doi:10.1111/pde.12584
3. Basdag H, Rainer BM, Cohen BA. Molluscum contagiosum: to treat or not to treat? Experience with 170 children in an outpatient clinic setting in the northeastern United States. Pediatr Dermatol. 2015;32(3):353-857. doi:10.1111/pde.12504
4. Eichenfield LF, McFalda W, Brabec B, et al. Safety and efficacy of VP-102, a proprietary, drug-device combination product containing cantharidin, 0.7% (w/v), in children and adults with molluscum contagiosum: two phase 3 randomized clinical trials. JAMA Dermatol. Published online September 23, 2020. doi:10.1001/jamadermatol.2020.323