5-Year Outcomes of Curettage Plus Imiquimod for Nodular Basal Cell Carcinoma

A recent study evaluating long-term outcomes of superficial curettage (SC) followed by imiquimod cream, 5%, versus surgical excision (SE) for nodular basal cell carcinoma (nBCC) found that SC plus imiquimod was substantially less effective at 5 years. The probability of remaining free from treatment failure at 5 years was 77.8% for SC plus imiquimod compared with 98.2% for SE, and the noninferiority margin was not met.

Interest in noninvasive treatment options for BCC has increased, particularly for superficial BCC, where imiquimod has demonstrated high long-term efficacy. However, evidence on long-term outcomes for nBCC treated with SC plus imiquimod is limited. This study aimed to determine whether this approach is noninferior to SE over a 5-year period.

Researchers conducted a secondary analysis of the Surgery Versus Combined Treatment With Curettage and Imiquimod for Nodular Basal Cell Carcinoma (SCIN) randomized clinical trial, which included 145 patients with primary histologically confirmed nBCC (4-20 mm). Patients were randomly assigned to either SC plus imiquimod (n = 73) or SE (n = 72) between 2016 and 2017 at two outpatient dermatology departments in the Netherlands. The primary outcome was the 5-year probability of remaining free from treatment failure, estimated using Kaplan-Meier analysis.

During the 5-year follow-up, 15 treatment failures occurred in the SC plus imiquimod group (including 5 between years 1 and 5), whereas only one treatment failure was observed in the SE group. The probability of remaining free from treatment failure at 5 years was 77.8% (95% CI, 65.7%-86.0%) for SC plus imiquimod and 98.2% (95% CI, 88.0%-99.8%) for SE. The relative risk of treatment failure was 15.93 (95% CI, 2.10-120.64), and the 95% confidence interval did not exclude the prespecified noninferiority margin of 5.22. Deaths unrelated to BCC occurred in 20 patients, and competing risk regression analysis yielded a subhazard ratio of 16.16 (95% CI, 2.18-119.72).

“This secondary analysis of a randomized clinical trial found that although it cannot be concluded that SC plus imiquimod is noninferior to SE, SC plus imiquimod was substantially less effective at 5 years after treatment,” the authors concluded. “The information in this trial can be used to counsel patients on the relative benefits and trade-offs of the different treatment options for nBCC.”

Reference

Verkouteren BJA, Nelemans PJ, Sinx KAE, et al. Imiquimod cream preceded by superficial curettage vs surgical excision for nodular basal cell carcinoma: a secondary analysis of a randomized clinical trial. JAMA Dermatol. Published online January 29, 2025. doi:10.1001/jamadermatol.2024.5572