中咽頭前壁粘表皮癌・甲状腺癌同時重複の1例

A case of simultaneous double cancer: mucoepidermoid carcinoma of the tongue base and thyroid cancer

はじめに

　中咽頭前壁は嚥下・音声機能に密接に関わる部位であり，癌の発症時には根治性と機能温存のため，治療法の選択に苦慮することがある。また，この部位での粘表皮癌の発症は稀で，同時重複癌の本邦報告例はこれまでに認めていない。今回，中咽頭前壁粘表皮癌と甲状腺癌の同時重複例を経験したため，診断と治療法について，考察を加えて報告する。

　A 67-year-old woman complained of a mass in the right side of her neck. The condition was diagnosed as a rare case of mucoepidermoid carcinoma of the tongue base and thyroid cancer occurring simultaneously.

　Tumor resection by the subhyoid approach, total thyroidectomy, cervical dissection, pectoralis major flap reconstruction of the tongue, cricopharyngeal muscle transection, laryngeal elevation, and tracheostomy were performed.

　Histopathological examination revealed p16-positive, high-grade mucoepidermoid carcinoma（pT4a pN1 pHM0 pVM1）of the tongue base and papillary cancer（pT1a pN1a）and follicular cancer（pT1b pN0）of the right and left thyroid lobes, respectively. Postoperative radiotherapy with cisplatin was started.

　In tongue base cancer cases, it is necessary to select a treatment that considers functional preservation.