Clinicopathologic analysis of cervical NTRK rearranged spindle cell tumor

LIU Xue-qing; SHEN Yan-ling; YANG Wen-sheng

doi:10.3969/j.issn.1007-8096.2025.05.012

Abstract：Objective To investigate the clinicopathological features of NTRK rearranged spindle cell tumor.Methods The histopathological features,immunophenotype and molecular genetic changes of a cervical NTRK rearranged spindle cell tumor were analyzed,and the key points of diagnosis and differential diagnosis were reviewed on related literatures.Results The patient,a 42-year-old woman,was presented with contact bleeding for 7 months.Electronic colposcopy showed a tumor in the vagina sized about 3cm.Microscopically,the tumor was mainly composed of diffuse spindle cells,which were arranged in ascicular,storiform or herringbone patterns,with variable degrees of lymphocyte infiltration in the background.The morphology of tumor cells showed mild atypia,with inconspicuous nucleoli or small nucleoli,and mitotic image was not easy to see.There was no necrosis.Immunohistochemical examination showed that CD34,S-100 and pan-TRK were diffusely expressed in spindle cells,SMA and CD10 were focally expressed,while ER,PR,Desmin,H-caldesmon,Calponin,CD99,STAT6 and ALK were all negative.The positive rate of p53 was about 5%,and the proliferation index of Ki-67 was about 20%.In molecular genetics,FISH detection showed separation of the red and green signals of NTRK1 and NTRK3 genes in tumor cells,which suggested that NTRK rearrangement was positive.The patient underwent excision of vaginal and cervical vegetation.More than 3 years after operation,extensive total hysterectomy and bilateral salpingo-oophorectomy along with pelvic lymph node dissection were performed due to recurrence.After a follow-up for more than 6 years,there had been no recurrence or metastasis.Conclusion NTRK rearranged spindle cell tumor is a newly discovered group of rare mesenchymal tumors with unique immunophenotype and molecular genetic characteristics,which is locally invasive and has great potential therapeutic benefits for TRK inhibitors.Correct diagnosis and identification of this tumor has great clinical significance.