Lung cancer presenting as a metastasis to the carpal bones: a case report.

Introduction: A first metastasis to the hand is extremely rare. Usually, an acrometastasis is a sign of very advanced disease, with the presence of previous multiple metastases elsewhere. The present paper is one of the very few case reports of first metastatic location to carpal bones. To date, only Lederer et al., in 1990, and Song and Yao in 2012, have described a metastasis to the trapezium from lung cancer.

Case Presentation: A 74-year-old Caucasian man was submitted to several physical examinations for thumb pain. The first diagnosis was tendonitis and the second diagnosis was thumb carpometacarpal osteoarthritis. Only when the patient was admitted to an internal medicine department for deterioration of his general condition and an enormous mass on his left hand was an open biopsy performed. It revealed a metastasis from large-cell lung carcinoma. A total-body scintigraphy and total-body computed tomography scan were negative for other secondary locations. The patient underwent an amputation at the distal third of the forearm.

Conclusion: Less than 20 case reports are available in the literature dealing with metastases to carpal bones. Very few cases are described as carpal metastases in the absence of other previous metastases, and only two articles, before the present one, have reported a metastasis to the trapezium. This case report teaches us two things: first, patient adherence to follow-up is extremely important; and, second, a thorough examination of diagnostic findings needs to be carried out at all times.