Gastric adenocarcinoma is not uncommon in the adult population, but in the pediatric population it is an extremely rare entity. A 13-year-old boy was referred to a pediatric oncology unit for evaluation of a tumor in the upper abdomen. Further investigation revealed an advanced stage gastric carcinoma with metastases suggestive for a hereditary cause. Awareness for uncommon diagnoses is a key issue in regard of accurate treatment and overall prognosis.