65-year-old male, T3a prostate cancer. Prior robotic lymph node dissection for staging. Post-operative lymphocele developed along the left external iliac vein. Percutaneous drainage decompressed the fluid collection and improved the leg swelling. Collection re-occurred, and the leg swelling worsened with severe pain. Venography and intravascular ultrasound (IVUS) showed severe narrowing of the external iliac vein. Stenting and venoplasty of the external iliac vein were performed with complete leg swelling and pain resolution.