What happened, in summary

A 69-year-old Japanese woman was referred for treatment after a routine upper endoscopy found gastric cancer at the gastric angle. Biopsy showed moderately to poorly differentiated adenocarcinoma extending into the submucosa. PET/CT also showed unusual activity in the bone marrow and para-aortic lymph nodes, raising concern about whether these findings represented spread of the cancer.

Bone-marrow testing did not show metastatic gastric cancer. Instead, it identified abnormal foamy cells suggesting a lysosomal storage disorder. Because the gastric cancer was considered operable, she underwent distal gastrectomy with para-aortic lymph-node dissection. Pathology confirmed poorly differentiated gastric adenocarcinoma. The abnormal cells in the lymph nodes were not gastric-cancer metastases and instead supported a diagnosis of Gaucher disease.

Further enzyme and genetic testing confirmed type 1 Gaucher disease, and she later began enzyme-replacement therapy for that separate condition. She received enzyme-replacement therapy for 16 months without side effects.