Takenobu Masao, Moritani Sueyoshi, Yoshioka Kana, Morisaki Tsuyoshi, Kitano Hiroya
Kusatsu General Hospital, Otolaryngology Head and Neck Thyroid Surgery, Shiga, Japan.
Tottori University Faculty of Medicine, Department of Otolaryngology, Head and Neck Surgery, Tottori, Japan.
Endocr J. 2018 Apr 26;65(4):479-483. doi: 10.1507/endocrj.EJ17-0553. Epub 2018 Feb 15.
Thyroid metastasis from head and neck squamous cell carcinoma (SCC) is a very rare form of rarely observed metastatic thyroid tumor. We herein report a case of thyroid metastasis from oropharyngeal SCC (OSCC). The patient was a 68-year-old male diagnosed with p16-positive tonsillar OSCC on the right side with multiple lymph node metastases and a thyroid mass, which was determined as metastatic p16-positive OSCC by immunohistochemistry of specimens collected by fine-needle aspiration cytology (FNAC). He received one cycle of induction chemotherapy followed by concurrent chemoradiotherapy. No visible primary lesions were observed after treatment. The disappearance of the tonsillar lesion was considered to be a complete response by the magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT). The thyroid lesion was also decreased, but a solid lesion with unclear boundaries in the right thyroid lobe remained. Therefore, the patient underwent total thyroidectomy to remove any residual tumor. Postoperative pathological evaluation revealed no residual viable carcinoma cells in the resected specimen. As illustrated in this case, immunohistochemistry of the FNAC specimen for p16 was successful in determining the thyroid tumor as a metastatic lesion from the oropharynx. Although radical radiotherapy might be sufficient to control thyroid gland metastasis of OSCC, in this case, early-stage remedial surgery was thought to be necessary for a secure radical cure.
头颈部鳞状细胞癌（SCC）发生甲状腺转移是一种极为罕见的转移性甲状腺肿瘤形式。我们在此报告一例口咽鳞状细胞癌（OSCC）发生甲状腺转移的病例。该患者为68岁男性，诊断为右侧p16阳性扁桃体OSCC伴多发淋巴结转移及甲状腺肿物，通过细针穿刺细胞学检查（FNAC）采集的标本进行免疫组化检查，确定为转移性p16阳性OSCC。他接受了一个周期的诱导化疗，随后进行同步放化疗。治疗后未观察到可见的原发灶。扁桃体病变消失，磁共振成像（MRI）和正电子发射断层扫描-计算机断层扫描（PET-CT）显示为完全缓解。甲状腺病变也有所缩小，但右甲状腺叶仍有一个边界不清的实性病变。因此，患者接受了全甲状腺切除术以清除任何残留肿瘤。术后病理评估显示切除标本中无残留的存活癌细胞。如本病例所示，FNAC标本的p16免疫组化成功确定甲状腺肿瘤为来自口咽的转移性病变。尽管根治性放疗可能足以控制OSCC的甲状腺转移，但在本病例中，早期补救性手术被认为对确保根治是必要的。
