Elacestrant, a novel selective estrogen receptor degrader, offers new treatment options for metastatic estrogen receptor–positive, human epidermal growth factor receptor 2–negative, estrogen receptor 1–mutated breast cancer. While its efficacy and safety are established, rare adverse effects such as drug-induced vasculitis remain unreported, posing diagnostic challenges. We report a case of biopsy-confirmed cutaneous leukocytoclastic vasculitis in a 33-year-old woman with advanced estrogen receptor/progesterone receptor–positive breast cancer after starting elacestrant. She developed palpable purpura on her lower extremities 2 weeks into therapy. An extensive work-up was unremarkable, and symptoms resolved after stopping elacestrant treatment and initiating corticosteroid therapy. This case highlights the need for awareness of rare immune-mediated reactions as elacestrant's use increases.
Vachhani et al. (Thu,) studied this question.