Bone metastasis as a recurrence of early papillary adenocarcinoma of the stomach

Papillary adenocarcinomas of the stomach are rare and associated with a high rate of lymphovascular invasion and distant metastasis. However, the association between papillary adenocarcinoma and bone metastasis in gastric cancer remains largely unexplored. We report a rare case of bone metastasis as a recurrence of early papillary adenocarcinoma of the stomach after curative surgery. A 75-year-old man with a pedunculated polyp at the pylorus of the stomach was diagnosed with papillary adenocarcinoma after biopsy of the lesion, and the polyp was surgically resected. Pathohistological examination revealed intramucosal cancer without lymphovascular invasion or lymph node metastasis. Eight months after surgery, imaging studies showed osteolysis in the right sacrum, and the lesion was diagnosed as a bone metastasis after biopsy. The patient received palliative chemotherapy and radiotherapy for the bone metastasis, which resulted in relief of his leg pain. Subsequently, he was provided supportive care when his condition deteriorated, and he died 8 months after the diagnosis of bone metastasis. Our case shows that bone metastasis should not be overlooked, even though it is rare in gastric cancer patients. Papillary adenocarcinoma of the stomach should be carefully followed up through imaging examinations, even after curative resection.