Unilateral Leg Swelling Caused by Common Femoral Vein Compression by a Hip Ganglion Cyst in the Groin

BACKGROUND: As a rare cause of unilateral leg swelling, extrinsic vein compression caused by intraperitoneal, retroperitoneal, or inguinal lesions has been noted. A rare case of leg swelling as a cause of extrinsic compression of common femoral vein from a ganglion cyst in the groin is presented. CASE PRESENTATION: A 38 year old man was referred with a 3 week history of left leg swelling. Following a radiological diagnosis of common femoral vein compression from a cystic groin mass, he firstly underwent needle aspiration. Although the lesion became somewhat smaller, his left leg was still swollen, and he underwent surgical excision of the lesion 2 days after needle aspiration. Histopathological features of the cystic wall were consistent with those of a ganglion cyst. He was discharged from the hospital with complete improvement of the leg swelling, and has remained free from recurrence 1 year after surgery. CONCLUSION: Femoral vein compression by a ganglion cyst in the groin is a very rare pathology; however, it should be kept in mind in the differential diagnosis of unilateral leg swelling.