Secondary analysis of a randomized trial of superficial curettage and imiquimod cream versus surgical excision for nodular basal cell carcinoma

The long-term efficacy of non-invasive treatment of nodular basal cell carcinoma (nBCC) is not clear. Secondary analysis of the randomized SCIN trial, at two centers in The Netherlands, compared 5-year outcomes after superficial curettage (SC) followed by imiquimod cream, 5%, versus surgical excision (SE) for primary nBCC of 4 to 20 mm. The analysis included 145 patients. The 5-year probability of remaining free from treatment failure was 77.8% after SC plus imiquimod and 98.2% after SE. The relative risk for treatment failure was 15.93 (95% CI 2.10-120.64). The 95% CI did not exclude the prespecified noninferiority relative risk margin of 5.22. Most treatment failures occurred in the first year after treatment. The authors conclude that although it cannot be excluded that SC plus imiquimod is noninferior to SE, SC plus imiquimod was substantially less effective at 5 years after treatment (visual abstract).