@article{oai:uoeh-u.repo.nii.ac.jp:00000812,
 author = {井上, 譲 and 厚井, 志郎 and 合原, 雅人 and 城田, ふみ and 矢吹, 慶 and 田上, 貴之 and 佐藤, 永洋 and 勝木, 健文 and 永田, 貴久 and 柴尾, 和徳 and 久岡, 正典 and 平田, 敬治 and Inoue, Yuzuru and Kohi, Shiro and Gobara, Masato and Joden, Fumi and Yabuki, Kei and Tanoue, Takayuki and Sato, Nagahiro and Katsuki, Takefumi and Nagata, Takahisa and Shibao, Kazunori and Hisaoka, Masanori and Hirata, Keiji},
 issue = {3},
 journal = {産業医科大学雑誌, Journal of UOEH},
 month = {Sep},
 note = {症例は70歳代女性．自覚症状は特になかった．近医にて甲状腺腫大を指摘され当科紹介．頸部エコーで甲状腺右葉下極に1.3 cm大，形状不整，辺縁粗雑，内部不均一，石灰化を伴う腫瘤を認めた．computed tomography（CT）で病変は胸骨甲状筋への浸潤が疑われ，両側頸部リンパ節腫大を認めたが，positron emission tomography（PET）-CTでは転移を疑う異常集積を認めなかった．細胞診では不整な濃染性核を有する異型上皮の大小の重積性あるいは乳頭状集塊を認め，乳頭癌が疑われた．以上，甲状腺乳頭癌の術前診断に対して甲状腺亜全摘と両側頸部中央区域リンパ節郭清を施行した．術後病理診断では胸骨甲状筋と右下副甲状腺への浸潤を伴う線維化の強い腫瘍が胞巣状に増生しており，核化傾向を伴っていたため扁平上皮癌が疑われ，また胞巣の一部に粘液を含んだ管腔構造を認め，粘表皮癌も疑われた．免疫染色ではcluster of differentiation 5（CD5）（+），tumor protein p63（p63）（+），KIT proto-oncogene receptor tyrosine kinase（c-KIT（CD117））（+），thyroglobulin（-），thyroid transcription factor-1（TTF-1）（-）であったことから胸腺様分化を示す癌（carcinoma showing thymus-like differentiation: CASTLE）の診断となった．CASTLEは組織学的に胸腺上皮腫瘍に類似した甲状腺癌である．多くのCASTLEの症例では未分化癌，低分化癌，扁平上皮癌と鑑別を要した．本症例も Hematoxylin-Eosin染色での検鏡では扁平上皮癌または粘表皮癌疑いであり，CD5を含む免疫染色を追加，診断が確定した．リンパ節転移や甲状腺外への浸潤は予後不良因子とされており，本症例でも今後，経過観察の継続が重要である．, The case presented herein was a 70-year-old woman who had no compliant, but had a mass in the lower part of the right lobe of the thyroid detected by ultrasound (US). The US image of the tumor, measuring 13 mm in diameter, showed a low and heterogeneous internal echo level with calcification and an irregular margin. The tumor appeared to extend to the adjacent sternothyroid muscle, and cervical lymph node swelling was detected in a computer tomography (CT) image, but no metastatic lesion was found by positron emission tomography (PET)-CT. In a fine needle aspiration cytology of the tumor, papillary thyroid carcinoma was suggested because of the atypical epithelial cells having some changes other than intranuclear inclusion bodies. A subtotal thyroidectomy and central neck lymph node dissection were performed. The excised tumor was histologically composed of irregular nests or sheets of atypical squamoid epithelial cells with some ductal structures that leached to the sternothyroid muscle and involved the right lower parathyroid gland. Carcinoma showing thymus-like differentiation (CASTLE) was diagnosed histopathologically and immunohistochemically with the following immunohistochemical results:Cluster of differentiation 5 (CD5) (+), tumor protein p63 (p63) (+), KIT proto-oncogene receptor tyrosine kinase(c-KIT(CD117)) (+), thyroglobulin (-), and thyroid transcription factor-1 (TTF-1) (-). CASTLE is a rare carcinoma of the thyroid that architecturally resembles thymic epithelial tumors. Many CASTLE patients have been misdiagnosed as other carcinomas, such as anaplastic carcinoma, poorly differentiated carcinoma or squamous cell carcinoma of the thyroid. Immunohistochemical examination, including CD5 played an important role in the final diagnosis of CASTLE, although the distinction from diagnosis as squamous cell carcinoma or mucoepidermoid carcinoma in Hematoxylin-Eosin staining was challenging in our case. Nodal metastasis and perithyroidal tumor extension of CASTLE can predict its worse prognosis. Thus, at least careful follow-up studies are mandatory in cases of CASTLE.},
 pages = {259--266},
 title = {甲状腺の胸腺様分化を示す癌Carcinoma Showing Thymus-Like Differentiation（CASTLE）of the Thyroidの１例},
 volume = {40},
 year = {2018}
}