Case of pseudoaneurysm mimicking a soft tissue sarcoma: a diagnostic pitfall.

Pseudoaneurysms represent a pulsating encapsulated hematoma in communication with the lumen of a ruptured vessel. We present a 33-year-old male with a pseudoaneurysm of the profunda femoris artery. At presentation and on further evaluation, he was diagnosed with a possible soft tissue sarcoma of the distal thigh. Catastrophic haemorrhage occurred at the time of a planned, elective open biopsy. This case report emphasises the importance of considering pseudoaneurysm as a crucial differential diagnosis in atypical swellings and scrutinising all suspected soft tissue tumours with a contrast study or a Doppler ultrasound.