Massive trapezial metastasis from gastric adenocarcinoma resected and reconstructed with a vascularized scapular bone graft

RATIONALE Isolated metastasis to the hand bones is very rare. Only seven cases of metastasis to the trapezium have been reported. To the best of our knowledge, this is the first report of a single metastasis to the trapezium from a gastric adenocarcinoma. PATIENT CONCERNS A 62-year-old man presented with pain and massive swelling in the right carpometacarpal joint of the thumb. DIAGNOSES The patient was diagnosed with trapezial metastasis of advanced gastric adenocarcinoma. INTERVENTIONS The patient underwent systemic chemotherapy with cisplatin and S-1, radiotherapy to the metastatic bone, and treatment with denosumab. One year later, the huge metastatic tumor was resected, and the hand was reconstructed using vascularized scapular bone. OUTCOMES Eighteen months postoperatively, the patient was satisfied with the appearance of the reconstructed hand and was able to use his right thumb in activities of daily living. LESSONS Although rare, metastasis to the trapezium should be considered in patients with persistent and progressive thumb CMC joint pain.