Treatment of hepatocellular carcinoma with a portal vein tumor thrombus and pulmonary metastases of rectal cancer with microsatellite stability using atezolizumab plus bevacizumab.

Herein, we report the successful treatment using atezolizumab plus bevacizumab of a patient with hepatocellular carcinoma (HCC) with a portal vein tumor thrombus and multiple pulmonary metastases from rectal cancer with microsatellite stability. This patient developed rectal cancer with synchronous pulmonary metastases and HCC. After resecting the primary lesion of the rectal cancer, transcatheter arterial chemoembolization was performed for the HCC. Drug therapy was planned for multiple pulmonary metastases of rectal cancer; however, the early development of recurrent HCC with portal vein tumor thrombus had to be highly prioritized, and atezolizumab plus bevacizumab was introduced. Following the disappearance of the recurrent HCC lesion, the metastatic pulmonary nodules shrunk into scar-like spots. The treatment for both HCC and pulmonary metastases of rectal cancer were considered to result in clinical complete response.