Supplementary Material for: A case report of gastric squamous cell carcinoma associated with pancreatic adenocarcinoma and literature review

It is common for advanced pancreatic adenocarcinoma to infiltrate the gastric wall, and the tumor cells invading the gastric wall are usually consistent with pancreatic adenocarcinoma. However, it is very rare for the tumor cells infiltrating the gastric wall to be squamous cell carcinoma. We report a case of a 57-year-old man who presented with weight loss for 2 months. CT revealed a pancreatic mass. Endoscopic ultrasound biopsy of the pancreatic mass confirmed pancreatic adenocarcinoma. He refused treatment and was discharged. Eight months later, he developed melena. CT revealed that the pancreatic mass had invaded the gastric wall. Gastric squamous cell carcinoma was confirmed by biopsy of gastric tissue under gastroscopy. The occurrence of this phenomenon provides certain clinical significance for the study of the mechanism of gastric squamous cell carcinoma.