Portal Venous Gas After Trans-arterial Radioembolization in Hepatocellular Carcinoma: A Rare but Critical Imaging Finding.

Transarterial radioembolization (TARE) is a relatively new treatment option available for unresectable hepatocellular carcinoma (HCC). TARE therapy involves the delivery of radiation directly to the tumor to cause tumor necrosis. Yttrium-90 (Y90) is commonly used as a source of radioembolization in TARE. TARE is very well tolerated and has a low rate of complications. Main complications of TARE for HCC include postembolization syndrome and radiation-induced injury to nearby organs such as the liver, gallbladder, and stomach, causing hepatitis, cholecystitis, or gastric ulceration. A side effect not previously described in TARE literature is portal venous gas after TARE therapy. We present the first ever reported case of portal and variceal venous gas in a 77-year-old male patient who had unresectable HCC and had previously failed chemotherapy. He underwent Y90 TARE for HCC. Following TARE, he presented with right upper quadrant abdominal pain, and imaging showed portal and variceal venous gas. He was treated with antibiotics, with resolution of symptoms and improvement in portal and variceal venous gas on repeat imaging.