Carpal tunnel syndrome due to an atypical deep soft tissue leiomyoma: The risk of misdiagnosis and mismanagement

Leiomyomas of the deep soft tissue are quite uncommon and occur even more rarely in upper extremity.

A 32-year old manual laborer man presented with a two-year history of numbness, tingling and burning pain in the palmar surface of the left hand and fingers. His medical history was unremarkable and no trauma episode was reported. According to the clinical examination and the result of median nerve conduction study (NCS) the diagnosis of carpal tunnel syndrome was established. Operative release of the transverse carpal ligament was subsequently performed but the patient experienced only temporary relief of his symptoms. MRI examination revealed a deep palmary located mass with well-defined margins and ovoid shape. Intraoperatively, the tumor was in continuity with the flexor digitorum superficialis tendon of the middle finger causing substantial compression to median nerve. Histopathological findings of the resected mass were consistent with leiomyoma. After two years the patient was pain-free without signs of tumor recurrence.

Despite the fact that reports on deep soft tissue leiomyoma are exceptional, this tumor had to be considered as differential diagnosis in painful non-traumatic hand syndromes especially in young patients.