What happened, in summary

A 76-year-old woman came to the emergency department after 2 months of abdominal discomfort, black stools, and intermittent pain. Endoscopy showed a large ulcerated stomach mass, and biopsy initially suggested well-differentiated adenocarcinoma. CT showed enlarged regional lymph nodes but no distant metastases. In June 2018, she underwent radical subtotal gastrectomy with D2 lymph-node dissection and reconstruction. Final pathology showed an unusual mixed tumor: most of the mass was gastric choriocarcinoma, while the remaining portion was well-differentiated tubular adenocarcinoma. The tumor had invaded the subserosa and involved 2 of 21 lymph nodes. β-hCG staining was strongly positive, and serum β-hCG measured 972.1 mIU/mL. She recovered from surgery and was discharged after 9 days. Chemotherapy was planned for the following week but was suspended because of general weakness. Two months after discharge, she returned with worsening weakness. CT then showed multiple liver metastases, making the latest disease Stage IV, and serum β-hCG had risen sharply to 443,560 mIU/mL. The cancer progressed rapidly, and she died from liver failure 5 months after surgery.