Gastropleural Fistula Following Combined TACE, Immunotherapy, and Bevacizumab in HCC: A Case Report.

Gastropleural fistula (GPF) is an extremely rare complication after treatment for liver cancer. We report a case of a 54-year-old man with hepatitis B virus (HBV)-related liver cancer who developed a GPF after multiple sessions of transarterial chemoembolization (TACE) combined with immunotherapy and targeted therapy. During the third treatment, because of arterial remodeling and changes in tumor vascular supply, the embolization route was changed to the left inferior phrenic artery. After the procedure, the patient presented with abdominal pain, chest pain, and fever. Metagenomic next-generation sequencing (mNGS) of the pleural effusion identified Porphyromonas endodontalis, and Pneumocystis jirovecii was also detected in the sputum. Upper gastrointestinal endoscopy and water-soluble contrast radiography confirmed a gastric fundus perforation with a fistulous communication to the pleural cavity. After multidisciplinary evaluation, the patient underwent laparoscopic fistula repair and had a favorable postoperative recovery. This case highlights that, while the combination of TACE, immunotherapy, and targeted agents may provide synergistic antitumor benefits, it also carries a potential risk of serious gastric complications.