High-dose-rate brachytherapy using Leipzig applicators for non-melanoma localized skin cancer.

Abstract

PurposeTechnological advances with commercial production of surface applicators allowed high-dose-rate (HDR) afterloading brachytherapy to overpass challenges associated with the delivery of superficial radiation when treating non-melanoma skin cancer (NMSC). We reviewed our single institutional experience using HDR to treat basal (BCC) and squamous cell (SCC) carcinomas.Material and methodsA retrospective review of all patients treated with HDR and Leipzig-style applicators for NMSC at the Radiation Oncology Department, AC Camargo Cancer Center, from March 2013 to December 2018 was performed.ResultsSeventy-one patients with 101 lesions (BCCs, 69.3% or n = 70) and median age 80 (range, 51-102) years old were evaluated. The median follow-up was 42.8 (range, 12-82) months. The 3-year and 5-year actuarial local control (LC) rates were 97.9% and 87.2%, respectively. On univariate analysis, treatments with EQD2 less than 50 Gy (p < 0.001) and dose per fraction smaller than 3 Gy (p < 0.001) were found to be statistically significant predictive factors of a worse outcome. On multivariate analysis, SCC had a worse prognosis over BCC (p = 0.007, HR = 2.3, CI: 1.2-6.6). All patients developed some degree of acute side effects graded 1 to 2. Grade 3 acute side effects were observed in 9 (8.9%) patients. Moreover, severe late side effects (grade 3), hypopigmentation, and telangiectasia were observed in 4 (3.9%) patients. No grade 4 acute or late side effects were seen in this cohort.ConclusionsHDR offers a convenient treatment schedule for patients and is associated with excellent LC. The most effective regimen, in terms of dose and fractionation, to treat superficial NMSC with HDR remains uncertain, but a moderate minimum EQD2 dose of 50 Gy should be used.