Curettage vs. cryosurgery for superficial basal cell carcinoma: a prospective, randomised and controlled trial

BACKGROUND: Basal cell carcinoma (BCC) is the most common cancer in the world and has a rising incidence. Current guidelines for low-risk BCC including superficial BCC (sBCC) recommend several treatment options including destructive treatment methods, such as cryosurgery with or without prior curettage or curettage and electrodesiccation. Curettage only (i.e. without subsequent cryosurgery or electrodesiccation) is a simple and quick destructive treatment method used for many benign skin lesions but has not been sufficiently evaluated for the treatment of sBCCs. OBJECTIVES: The objective was to compare the effectiveness of curettage vs. cryosurgery for sBCCs in terms of overall clinical clearance rates after 1 year as well as wound healing times. METHODS: A single-centre non-inferiority clinical trial was conducted. Non-facial sBCCs with a diameter of 5-20 mm were randomised to either cryosurgery using one freeze-thaw cycle or curettage. At follow-up visits, treatment areas were evaluated regarding the presence of residual tumour after 3-6 months and recurrence after 1 year. Further, wound healing times were assessed. RESULTS: In total, 228 sBCCs in 97 patients were included in the analysis. At 3-6 months, no residual tumours were seen in any of the treated areas. After 1 year, the clinical clearance rates for curettage and cryosurgery were 95.7% and 100%, respectively (P = 0.060). However, the non-inferiority analysis was inconclusive. Wound healing times were shorter for curettage (4 weeks) compared to cryosurgery (5 weeks; P < 0.0001). Overall, patient satisfaction at 1 year was high. CONCLUSIONS: Both treatment methods showed high clinical clearance rates after 1 year, whilst curettage reduced the wound healing time.