鞍区原发性软骨肉瘤5例临床病理学观察

Primary sellar chondrosarcoma:a clinicopathological analysis of five cases

目的探讨鞍区原发性软骨肉瘤的临床病理学特征及诊治要点。方法回顾性分析5例鞍区原发性软骨肉瘤的临床病理学特征、影像学表现及免疫表型,行免疫组化和分子检测,并复习相关文献。结果5例患者均为女性,年龄16~53岁,临床症状以头痛及视力障碍为主,均行颅底肿瘤切除术。镜检:肿瘤由软骨细胞和丰富的黏液样软骨基质组成,呈分叶状,瘤细胞轻-中度异型,可见双核细胞,核分裂象罕见。免疫表型:肿瘤细胞S-100蛋白和vimentin均阳性。1例肿瘤细胞IDH-1阳性。CKpan、EMA和Brachyury均阴性,Ki-67增殖指数为2%~5%。3例行IDH分子检测,其中1例呈IDH-1 R132L突变,2例为野生型。4例获得随访,均存活,其中2例复发。结论鞍区软骨肉瘤是一种罕见的鞍区恶性肿瘤,术前诊断具有挑战性。需与软骨样脊索瘤、脊索样脑膜瘤及骨外黏液样软骨肉瘤等鉴别,治疗首选手术切除。

Purpose To investigate the clinicopathological features, diagnosis and treatment of primary sellar chondrosarcoma. Methods Clinicopathological features, imaging findings and immunophenotyping of the five cases of primary chondrosarcoma in the sellar region were retrospectively analyzed, with immunohistochemistry and molecular testing, and the relevant literature was reviewed. Results All the 5 patients in this group were female, aged 16-53 years, with headache and visual impairment as the main symptoms. All patients underwent skull base tumor resection. Histologically, the tumor was composed of chondrocytes and abundant myxoid cartilage matrix, which showed a lobular pattern. The tumor cells showed mild-moderated atypia, with binucleated forms, and mitotic figures were rare. Immunohistochemically, the tumor cells were uniformly positive for S-100 (5/5) and vimentin (5/5), only one out of five cases showed IDH-1 positivity. All cases were negative for CKpan, EMA and Brachyury, and the Ki-67 index was 2%-5%. IDH molecular testing was performed in three cases;One showed IDH-1 R132L mutation and two were wild type. Four patients with follow-up data were alive, and 2 patients had tumor recurrence. Conclusion Primary sellar chondrosarcoma is a rare malignant tumor of sellar region. The preoperative diagnosis of sellar chondrosarcoma remains challenging. It should be differentiated from chondroidchordoma, chordoid meningioma and extraosseous myxoid chondrosarcoma morphologically. Surgical resection is the main treatment method at present.