A Prompt Diagnosis and Treatment of a Case of Nuclear Protein of the Testis Carcinoma Characterized by a Bronchial Lesion and High Serum Alpha-fetoprotein Level Following Genomic Testing

Nuclear protein of the testis carcinoma (NUTC) is a rare and aggressive malignancy. We herein report a case of NUTC in the lung characterized by a bronchial lesion and elevated alpha-fetoprotein levels. A 35-year-old Japanese man presented to our institution with suspected advanced lung cancer based on a histological examination. Subsequently, next-generation sequencing (NGS) yielded a positive BRD4-NUTM1 fusion. In addition, positive NUT immunostaining of the lung biopsy specimen confirmed NUTC in the lungs. Systemic chemotherapy and radiotherapy showed a temporary response, with decreased serum alpha-fetoprotein levels. We highlight this case of a prompt diagnosis by NGS of NUTC in a young individual with a rapidly progressing tumor.