Non-gestational choriocarcinoma with hyperprogression on pembrolizumab: A case report and review of the literature

Non-gestational choriocarcinoma is a rare and aggressive germ cell tumor. Here we present the case of a post-menopausal 49-year-old woman who presented with metastatic disease and initially achieved a complete radiographic and biomarker response with seven cycles of EMA-CO chemotherapy. Upon recurrence, she received two separate courses of chemotherapy, initially with paclitaxel/cisplatin/etoposide and later FOLFOX. Tumor analysis revealed 22% PD-L1 positivity (tumor proportion score) and she was treated with pembrolizumab. However, βhCG levels rose abruptly and uncharacteristically through all three cycles of anti-PD1 therapy. The patient developed dyspnea on exertion, cough, and right flank pain. CT imaging demonstrated marked progression of liver metastases and innumerable new pulmonary metastases and the patient died 10 weeks after starting pembrolizumab. Here we describe the clinical presentation and management of this patient, along with analysis of molecular aberrations which could potentially explain hyperprogression in response to pembrolizumab.