Gastric adenocarcinoma presenting with thromboembolism in a 13-year-old boy.

Abdominal pain is a frequent complaint in the pediatric emergency department. A 13-year-old boy presented with complaints of abdominal pain, hematemesis, headache, and leg pain. Further investigation revealed an advanced-stage gastric adenocarcinoma with multiple thromboembolism including the greater saphenous vein and nonbacterial thrombotic endocarditis. This case points out the challenges of diagnosing this rare condition and treating the primary tumor and thromboembolism in the setting of both hypercoagulable state and gastrointestinal bleeding.