Fatal intratumoral hemorrhage in a patient with hepatocellular carcinoma following successful treatment with atezolizumab/bevacizumab: A case report.

Background: Atezolizumab/bevacizumab is emerging as the new standard for advanced hepatocellular carcinoma (HCC), with ongoing real-world implementation to study its effectiveness. As the use of atezolizumab/bevacizumab increases, various side effects have been reported in clinical practice, most notably increased bleeding caused by bevacizumab.

Case Summary: In this case report, we present a rare and fatal case of intratumoral hemorrhage in a patient with advanced HCC following successful treatment with atezolizumab/bevacizumab. A 63-year-old male diagnosed with HCC initially underwent four cycles of intra-arterial chemotherapy. However, follow-up abdominal computed tomography (CT) revealed disease progression. Subsequently, the treatment plan was modified to atezolizumab/bevacizumab. After the fifth cycle of atezolizumab/bevacizumab, CT showed partial regression of HCC. One week later, he visited the emergency room due to severe abrupt abdominal pain. Abdominal CT revealed focal rupture of HCC in the medial segment inferior portion with active bleeding and a large amount of hemoperitoneum. Angiography was performed on the same day, and embolization of A4 and A8 branches using lipiodol and gelfoam was implemented. Despite successful hemostasis, the patient subsequently developed liver failure and died.

Conclusion: Atezolizumab/bevacizumab for advanced HCC suggests that intratumoral hemorrhage may be crucial despite good tumor response after immunotherapy, emphasizing the continuous monitoring of this side effect.