Primary Pure Choriocarcinoma of the Colon Complicated by Tumor Lysis Syndrome and Choriocarcinoma Syndrome

Primary choriocarcinoma of the colon is exceedingly rare, often presenting as mixed histology. Pure colonic choriocarcinoma is associated with an aggressive course and complications such as tumor lysis syndrome (TLS) and choriocarcinoma syndrome (CS) can be life-threatening. We report a 68-year-old man presenting with widely metastatic disease initially misdiagnosed as poorly differentiated carcinoma. Colonoscopy revealed an ulcerated mass at the hepatic flexure. Histopathology confirmed choriocarcinoma and a markedly elevated serum beta human chorionic gonadotropin level (>215 000 mIU/mL). Following carboplatin and paclitaxel, he developed sequential TLS and CS, ultimately leading to his death. This case highlights the diagnostic challenges and life-threatening complications of this malignancy.