Paraneoplastic neurological disorder (PND) is a condition due to immune cross-reactivity between the tumour cells and the normal tissue, whereby the “onconeural” antibodies attack the normal host nervous system. It can present within weeks to months before or after the diagnosis of malignancies. Nasopharyngeal carcinoma is associated with paraneoplastic syndrome, for example, dermatomyositis, and rarely with a neurological disorder. We report on a case of nasopharyngeal carcinoma with probable PND. Otolaryngologists, oncologists and neurologists need to be aware of this condition in order to make an accurate diagnosis and to provide prompt treatment.

Abscess ; pathology ; Acute Disease ; Female ; Humans ; Infant ; Mastoid ; pathology ; Otitis Media ; diagnosis ; Rhabdomyosarcoma ; diagnosis

Objective:To investigate the clinical and pathological features of pediatric NTRK-rearranged tumors.Methods:Four NTRK-rearranged soft tissue tumors and one renal tumor at Shanghai Children′s Medical Center, Shanghai Jiaotong University and Singapore KK Women′s and Children′s Hospital from January 2017 to September 2019 were identified. Pan-TRK immunohistochemistry, and the ALK and ETV6 gene break-apart fluorescence in situ hybridizations (FISH) were performed. NTRK gene rearrangement was detected using sequencing-based methods.Results:There were 3 males and 2 females in this study. The patients were between 3 months and 13 years of age. Histologically, the tumors were infiltrative spindle cell tumors with variable accompanying inflammatory cells. Immunohistochemistry showed positive reactivity for pan-TRK in all tumors, with nuclear staining for NTRK3 fusion, and cytoplasmic staining for NTRK1 fusion. The molecular testing revealed NTRK gene fusions (one each of TPM3-NTRK1, ETV6-NTRK3 and DCTN1-NTRK1, and two cases of LMNA-NTRK1). Two patients were receiving larotrectinib. The others were are well without disease, with follow-up durations of 9 to 29 months.Conclusions:NTRK-rearranged mesenchymal tumors from soft tissue sites and kidney are identified. A novel DCTN1-NTRK1 fusion is described. Pan-TRK immunohistochemistry is useful for diagnosis. NTRK-targeted therapy may be an option for unresectable, recurrent or metastatic cases.