Hepatocellular Carcinoma Presenting with Pseudoprogression in a Patient Receiving Atezolizumab Plus Bevacizumab Combination Therapy.

A 65-year-old man with hepatocellular carcinoma and lung metastasis was treated with a combination of atezolizumab and bevacizumab. Subsequently, the patient developed fever and new liver lesions, which were considered to indicate a pseudoprogression. Despite this, the treatment was continued. Three months later, computed tomography scans demonstrated that the new lesions had disappeared and both the primary tumor and metastases had shrunk. A partial response was achieved and maintained for two years. A histological examination revealed a predominance of CD8-positive lymphocytes and programmed death-ligand 1-positive tumor-associated macrophages, which may predict a positive response to this therapy. Pseudoprogression may therefore be a favorable prognostic factor in hepatocellular carcinoma.