Tumor lysis syndrome is an oncologic emergency that can present with variable symptoms and is truly a laboratory-based diagnosis without pathognomonic clinical findings. The classical teaching is to consider this diagnosis in cancer patients undergoing chemotherapy. We present the case of a 66-year-old female with newly diagnosed metastatic liver adenocarcinoma, not on chemotherapy, who was diagnosed with spontaneous tumor lysis syndrome. Cognizance of this syndrome and associated laboratory findings are paramount to diagnosis and rapid intervention
