Development of Hepatocellular Carcinoma During Nivolumab Treatment for Recurrent Non-Small Cell Lung Cancer: A Case Report

Nivolumab, a monoclonal antibody targeting programmed cell death 1 (PD-1), is the standard second-line therapy for advanced non-small cell lung cancer (NSCLC). In the current immunotherapy era, it is often difficult to evaluate the therapeutic effect, disease progression, and pseudo-enlargement of the tumor or the emergence of another etiology. In the present report, we describe a 79-year-old patient with hepatocellular carcinoma (HCC) newly detected during nivolumab treatment for recurrent NSCLC. When the patient was 73 years old, he had suffered from NSCLC and received concurrent chemoradiotherapy comprising cisplatin and docetaxel, achieving a complete response. Six years after the chemoradiotherapy, the patient had multiple lung and hepatic lesions. We thus started the treatment with nivolumab for recurrent NSCLC. All those lesions responded to nivolumab over nine cycles. By contrast, a lesion was newly detected in the medial segment of left hepatic lobe, liver segment 4 (S4), and was gradually getting larger, as judged by computed tomographic scan. Liver biopsy revealed the growing lesion to be a well-differentiated HCC. Consequently, the patient was treated with radiofrequency ablation to HCC, while nivolumab treatment was continued for NSCLC. Immunohistochemical analysis of the HCC specimens revealed nuclear accumulation of β-catenin compared with normal liver cells and undetectable expression of program death ligand 1 (PD-L1). Such expression profiles of β-catenin and PD-L1 in HCC may be responsible for the resistance against nivolumab treatment. Immunohistochemical features of the biopsy specimens may be predictive of the effectiveness of the immunotherapy in HCC.