SMARCB1/INI1缺失的低分化脊索瘤的临床病理特征OA北大核心CSTPCD

Purpose To investigate the clinical pathology of SMARCB1/INI1-deficient poorly differentiated chordoma.Methods Ten patients with poorly differentiated chordoma were collected.The expression of CK,vimentin,INI1,and Brachyu-ry was detected using EnVision immunohistochemistry.Clinical characteristics,histopathological features,as well as related prognosis were analyzed and the literature was reviewed.Results Among the 10 cases,including 5 males and 5 females,the mean age of onset was 4 years.10 cases were located in the cliv-us and had bone invasion,3 involved the cervical spine(18.2％).In morphology,tumor cells showed sheet or nest mass growth,with epithelioid tumor cells.The nucleus was round or oval,with obvious atypia and visible nucleoli.Mitotic figures were active.Lymphocytic infiltration was noted in the stroma.Tumor cells in 10 cases were positive for CK,Vimen-tin,EMA and Brachyury with loss of SMARCB1/INI1 expres-sion.Ten patients were followed-up postoperatively.5 patients had tumor recurrence(median progression-free survival was 4 months)and 7 died(median overall survival was 5 months).Conclusion SMARCB1/INI1-deficient poorly-differentiated chordoma is a relatively rare bone tumor with poor prognosis and challenging diagnosis.Understanding the clinical pathological characteristics of this tumor has great significance for diagnosis and treatment.