Ou L Q, Xi S Y, Fu L Y, Zhang W G, Xian X Y, Liu Y H, Yun J P, Zeng J, Hu W M
Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou510060, China.
Department of Neurosurgery, Jiangmen Central Hospital, Guangdong Province, Jiangmen529000, China.
Zhonghua Bing Li Xue Za Zhi. 2024 Dec 8;53(12):1231-1237. doi: 10.3760/cma.j.cn112151-20240530-00353.
To investigate the clinicopathological features, immunophenotype, molecular characteristics, and differential diagnosis of primary intracranial DICER1-mutant sarcoma in order to better understand this tumor type. A retrospective analysis was conducted on 7 cases of primary intracranial DICER1-mutant sarcoma diagnosed in the Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China between 2021 and 2023 using next-generation sequencing. At the same time, 10 gliosarcomas, 4 intracranial FET::CREB fusion-positive mesenchymal tumors, 4 malignant meningiomas, 3 malignant solitary fibrous tumors, 3 malignant peripheral nerve sheath tumors, 3 synovial sarcomas and 3 rhabdomyosarcomas (total 30 cases) were selected as control. Among the 7 patients with primary intracranial DICER1-mutant sarcoma, 6 were male and 1 was female, aged 10-32 years (median, 23 years). The tissue morphology was predominantly spindle or pleomorphic sarcoma-like, with 6 cases exhibiting eosinophilic globules, and 3 cases showing rhabdomyoblastic or rhabdomyosarcoma-like cell differentiation. Immunohistochemistry revealed focal desmin expression in 3 cases (3/7), ATRX loss in 3 cases (3/7), and p53 mutant pattern in 4 cases (4/7). Additionally, 4 cases (4/7) showed focal or diffuse SALL4 expression, whereas the control cases (30 cases) did not exhibit SALL4 protein expression, suggesting that SALL4 may possess certain auxiliary diagnostic value. Next-generation sequencing confirmed that all 7 cases of primary intracranial DICER1-mutant sarcoma harbored mutations in the DICER1 gene, with 5 cases having the mutation site at p.E1813D. Until May 2024, all 7 patients were alive. Primary intracranial DICER1-mutant sarcoma is a rare tumor. Understanding its morphological characteristics, immunohistochemical and molecular markers and differential diagnosis is crucial to avoid misdiagnosis and to improve diagnostic accuracy of this tumor.
为了更好地了解原发性颅内DICER1突变肉瘤这种肿瘤类型，对其临床病理特征、免疫表型、分子特征及鉴别诊断进行研究。采用二代测序技术，对2021年至2023年期间在中国广州中山大学肿瘤防治中心病理科确诊的7例原发性颅内DICER1突变肉瘤进行回顾性分析。同时，选取10例胶质肉瘤、4例颅内FET::CREB融合阳性间叶性肿瘤、4例恶性脑膜瘤、3例恶性孤立性纤维瘤、3例恶性外周神经鞘瘤、3例滑膜肉瘤和3例横纹肌肉瘤（共30例）作为对照。7例原发性颅内DICER1突变肉瘤患者中，男性6例，女性1例，年龄10 - 32岁（中位年龄23岁）。组织形态学上主要为梭形或多形性肉瘤样，6例可见嗜酸性小球，3例显示横纹肌母细胞或横纹肌肉瘤样细胞分化。免疫组化显示3例（3/7）局灶性结蛋白表达，3例（3/7）ATRX缺失，4例（4/7）p53呈突变型。此外，4例（4/7）显示局灶性或弥漫性SALL4表达，而对照病例（30例）未显示SALL4蛋白表达，提示SALL4可能具有一定的辅助诊断价值。二代测序证实7例原发性颅内DICER1突变肉瘤均存在DICER1基因突变，5例突变位点为p.E1813D。截至2024年5月，7例患者均存活。原发性颅内DICER1突变肉瘤是一种罕见肿瘤。了解其形态学特征、免疫组化及分子标志物和鉴别诊断对于避免误诊及提高该肿瘤的诊断准确性至关重要。
