Remarkable Response to Pembrolizumab in Metastatic Cancer of Unknown Primary.
BACKGROUND Cancer of unknown primary (CUP) is aggressive, with limited options and poor prognosis. Mismatch repair-deficient (dMMR) CUP is rare, and reports of its response to immunotherapy are scarce. CASE PRESENTATION A 52-year-old man presented with extensive liver metastases and severe hepatic dysfunction (biliru...