Adjuvant Trastuzumab Emtansine (T-DM1) and Concurrent Radiotherapy for Residual Invasive HER2-positive Breast Cancer: Single-center Preliminary Results
Résumé
Objectives:The treatment of nonmetastatic HER2-positive breast cancer with residual invasive disease using concurrent Trastuzumab emtansine (T-DM1) and radiotherapy appears to be an effective option. Our aim was to evaluate the acute side effects of this treatment regime.Methods:Fourteen patients were treated between March 2019 and April 2020 concurrent T-DM1 and radiotherapy. Left ventricular ejection fraction was assessed at baseline, before and after radiotherapy. All toxicities were evaluated using Common Terminology Criteria of Adverse Events (CTCAE) version 3.0.Results:The median age was 55 years (range 36 to 72). All patients received total dose of 50 Gy for the breast/ chest wall, 10 patients got lymph node irradiation, 4 patients received an additional tumor bed boost. The most common side effect was grade 1 radiodermatitis. A reversible grade 2 left ventricular ejection fraction decrease occurred in 2 patients. During our examination 3 patients showed alanine aminotransferases increase after the cycle 4 of T-DM1, 1 patient had grade 1, 1 patient grade 2, and 1 patient grade 3 alanine aminotransferase increases.Conclusions:The acute toxicity rate especially focusing on skin and cardiac toxicity were assumed acceptable in our cohort. To safely administer this concomitant treatment, further examination and prospective data are needed.