Giant extraskeletal chondroma of the index finger: a case report

We report a case of giant extraskeletal chondroma arising from the index finger. The patient, a 62-year-old man, noticed the tumour in his right index finger about 30 years ago. X-ray and computed tomography (CT) scan revealed a 5-cm calcified soft-tissue tumour on the radial side of the proximal phalanx without any destruction of the cortex. Magnetic resonance imaging (MRI) showed iso-signal intensities on T1-weighted image (WI), spotted high-signal intensities on T2 WI and no enhanced areas after gadolinium injection. Because these studies could not definitively determine whether the tumour was benign or malignant, we performed a needle biopsy. As we suspected extraskeletal chondroma, we performed a marginal excision. The tumour adhered to the A1 pulley. Pathological diagnosis was extraskeletal chondroma, as expected. Approximately 80% of extraskeletal chondromas arise in hands or feet. Most reported cases are <3 cm. Literature review failed to uncover any cases larger than the tumour in our patient.