Daily use of 5-fluorouracil cream gives better cosmetic outcomes than excision for treatment of Bowen's disease

Furthermore, the non-inferiority of methylaminolevulinate photodynamic therapy (MAL-PDT) to excision could not be concluded.

Based on the findings published in the Journal of the American Academy of Dermatology, the researchers suggest giving preference to 5-fluorouracil over excision and MAL-PDT in treating Bowen’s disease.

Bowen disease is an in situ squamous cell carcinoma (SCC) that has the potential for significant lateral spread. Larger lesions can reach several centimetres in diameter. Multiple treatment options have been described for Bowen’s disease and are established with disadvantages and advantages. The disease occurs most often in elderly patients and is frequently located on body sites with poor wound healing. Therefore there is a need for non-invasive/non-destructive but effective treatment options.

The different options for BD treatment include curettage with cautery, cryotherapy, 5-fluorouracil (5-FU), excision, radiotherapy, imiquimod, laser, and photodynamic therapy.

There is a lack of RCTs (randomized controlled trials) comparing the effectiveness of 5-fluorouracil cream, methylaminolevulinate photodynamic therapy and surgical excision in patients with Bowen’s disease. Therefore, Shima Ahmady, Maastricht University Medical Center, Maastricht, the Netherlands, and colleagues conducted a multicenter non-inferiority trial investigating patients with a histologically proven Bowen’s disease of 4-40mm.

250 patients were randomly assigned between 2019 and 2021 to excision with a 5mm margin, two sessions of MAL-PDT with one-week intervals, or 5% 5-fluorouracil cream twice daily for four weeks.

The study's primary outcome was determined as the proportion of patients with sustained clearance at 12 months after treatment. A non-inferiority margin of 22% was used.

The study led to the following findings:

• The proportion of patients with sustained clearance was 97.4% after excision, 85.7% after 5-fluorouracil and 82.1% after MAL-PDT.
• Absolute differences were -11.7% for 5-fluorouracil versus excision and -15.4% for MAL-PDT versus excision.
• Both non-invasive treatments significantly more often led to good or excellent cosmetic outcomes.

"Based on our predefined non-inferiority margin of 22%, we found 5-fluorouracil to be non-inferior to excision and associated with better cosmetic outcomes," the researchers wrote. "For MAL-PDT non-inferiority to excision cannot be concluded."

"Therefore, 5-fluorouracil should be preferred over excision and MAL-PDT for treating Bowen’s disease," they concluded.

Reference:

Ahmady, S., Nelemans, P. J., Kelleners-Smeets, N. W., Arits, A. H., De Rooij, M. J., Kessels, J. P., Essers, B. A., & Mosterd, K. (2023). Surgical excision versus topical 5% 5-fluorouracil and photodynamic therapy in treatment of Bowen’s disease: A multicenter randomized controlled trial. Journal of the American Academy of Dermatology. https://doi.org/10.1016/j.jaad.2023.08.076