Abstract: Nuclear protein in testis (NUT) carcinoma (NC) is a poorly differentiated malignant tumor with a poor prognosis, which is caused by the NUTM1  gene rearrangement. Positive staining of NUT using immunohistochemistry (IHC) or gene rearrangement of NUTM1  revealed by genetic analysis, such as fluorescence in situ hybridization (FISH) or next-generation sequencing (NGS), are important strategies used for accurate diagnosis. In the current study, we present a case of NC in an 18-year-old man who had a chief complaint of nasal congestion, nasal bleeding, and anosmia. Magnetic resonance imaging revealed a mass in the nasal cavity and nasal septum. The initial pathological diagnosis was basaloid squamous cell carcinoma. Based on the tumor location and abrupt keratinization, further genetic tests were performed, and NC was diagnosed using FISH, which was further verified by IHC. However, neither DNA-based NGS nor RNA-based NGS revealed the NUTM1  gene rearrangement. Using this case as a basis, we have reviewed the related literature, compared the common diagnostic methods of NC, and discussed the advantages and limitations of current tools employed for molecular analysis of the gene fusion.
Keywords: NUTM1, NUT midline carcinoma, FISH, next-generation sequencing, gene rearrangement