BACKGROUND Sclerosing mucoepidermoid carcinoma with eosinophilia is a rare form of thyroid carcinoma. The underlying molecular mechanisms of sclerosing mucoepidermoid carcinoma with eosinophilia tumorigenesis remain unknown. CASE PRESENTATION We present two cases of sclerosing mucoepidermoid carcinoma with eosinophilia, both with a concurrent papillary thyroid carcinoma. Patient 1, a 70-year-old Caucasian woman, presented with sclerosing mucoepidermoid carcinoma with eosinophilia with distant renal metastasis and coexisting papillary thyroid carcinoma. Patient 2, a 74-year-old Caucasian woman with a remote history of thyroid cancer treated with thyroidectomy, presented with locoregionally invasive sclerosing mucoepidermoid carcinoma with eosinophilia and recurrent papillary thyroid carcinoma in the thyroid bed. BRAF mutation studies were performed on the sclerosing mucoepidermoid carcinoma with eosinophilia tumors. In both cases, sclerosing mucoepidermoid carcinoma with eosinophilia was positive for the BRAF V600E mutation by polymerase chain reaction. Patient 1 is the first reported case of sclerosing mucoepidermoid carcinoma with eosinophilia with renal metastasis, to the best of our knowledge. CONCLUSIONS Our findings suggest, for the first time, to our knowledge, involvement of the RAS-RAF-MEK-ERK signaling pathway in the pathogenesis of sclerosing mucoepidermoid carcinoma with eosinophilia. Thus, BRAF inhibitors may prove to be a useful targeted medical therapy in the treatment of a subset of patients with aggressive sclerosing mucoepidermoid carcinoma with eosinophilia tumors who exhibit BRAF activating mutation.

中文翻译：

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在患有甲状腺嗜酸粒细胞增多的硬化性粘液表皮样癌中激活BRAF突变：两例病例并文献复习。

背景技术患有嗜酸性粒细胞增多的硬化粘液表皮样癌是甲状腺癌的一种罕见形式。硬化黏液表皮样癌伴嗜酸性粒细胞增多的潜在分子机制仍然未知。病例介绍我们介绍了2例硬化性黏液表皮样样癌伴嗜酸性粒细胞增多症，均伴有甲状腺乳头状癌。患者1，一名70岁的白种女人，患有硬化性粘液表皮样样癌，嗜酸性粒细胞增多症，伴有远处肾转移和并存甲状腺乳头状癌。患者2，一名74岁的甲状腺癌病史较轻的白人妇女，接受甲状腺切除术治疗后，出现局部浸润性硬化性粘液表皮样样癌，伴有嗜酸性粒细胞增多和甲状腺乳头状癌复发。在患有嗜酸性粒细胞增多的硬化性粘液表皮样癌中进行了BRAF突变研究。在这两种情况下，硬化性黏液表皮样癌伴嗜酸性粒细胞增多的BRAF V600E突变均通过聚合酶链反应呈阳性。据我们所知，患者1是第一个报告的硬化性粘液表皮样样癌伴嗜酸性粒细胞增多并伴有肾转移的病例。结论我们的研究结果首次表明，据我们所知，RAS-RAF-MEK-ERK信号通路与硬化性黏液表皮样癌伴嗜酸性粒细胞增多的发病机理有关。因此，BRAF抑制剂可能被证明是治疗具有侵袭性硬化性粘液表皮样样癌且嗜酸性粒细胞增多的具有BRAF活化突变的部分患者的有效靶向药物治疗。