Fig. 4

a Intraoperative findings for case 2. A small hard mass was detected in the posterior gastric wall (arrow). b Partial resection of the posterior gastric wall was performed. c Pathological findings. Many abnormal luminal structures (adenocarcinoma) were confirmed in the resected gastric muscle layer (hematoxylin and eosin staining, loupe image). d Pathological findings. The findings of gastric tumor were similar to those of the primary pancreatic cancer, indicating that gastric tumor was a recurrence due to needle tract seeding from pancreatic cancer (hematoxylin and eosin staining)