Tumor Cells Identified by Single-Cell RNA Sequencing in A Patient with Nasopharyngeal Mass: A Case Report

Nasopharyngeal cancer is endemic in South China.Early diagnosis and treatment are important for the prognosis of patients.For patients who could not be pathologically diagnosed for the lack of tumor cells in biopsy specimen, treatment might be delayed.Here we report a male patient from endemic region of nasopharyngeal carcinoma with a mass in nasopharynx on magnetic resonance imaging and elevated blood Epstein-Barr virus DNA copies.Nasopharyngeal biopsies were repeated for three times while the pathological examination only showed inflammation of the squamous epithelium with few variant cells.Single-cell RNA sequencing was performed with biopsy tissues and only nine tumor cells were recognized.The patient was pathologically confirmed as undifferentiated non-keratinizing carcinoma several months later.We suspect that single-cell RNA sequencing may contribute to the early diagnosis in cases with very few tumor cells.