Pediatric Gastric Adenocarcinoma Presenting As Hip Pain

The third most lethal cancer in the world is gastric adenocarcinoma, which is uncommon in children. Patients with gastric adenocarcinoma typically experience vomiting, abdominal pain, anemia, and weight loss. We present a case of a 14.5-year-old male with gastric adenocarcinoma that manifested as left hip pain, epigastric pain, dysphagia, weight loss, and melena. Physical exam revealed cachexia, jaundice, a palpable epigastric mass, palpable liver edge, and left hip tenderness. Laboratory tests showed microcytic anemia, increase in carcinoembryonic antigen (CEA), and abnormal liver function test. Endoscopy revealed a cardial mass extending to the esophagus involving the gastroesophageal junction (GEJ). The gastric mass biopsy was consistent with invasive, moderately-differentiated gastric adenocarcinoma, which confirmed the diagnosis of gastric adenocarcinoma. Furthermore, a bone isotope scan revealed mildly hypervascular active bone pathology within the left proximal femur implying possible metastasis. Computed tomography scans and barium swallow were also helpful in supporting the diagnosis. Our case report emphasizes that gastric adenocarcinoma should be encompassed in the differential diagnosis of pediatric patients with hip pain.