區分頸動脈體副神經節瘤和疑似復發性乳頭狀甲狀腺癌的頸部腫瘤有時很困難。方法： 我們報告了一名66 歲的女性，既往有甲狀腺乳頭狀癌病史，兩年後在右下頜下區發現了一個 3 厘米大小的一個硬質且快速生長的腫塊。最初經細胞學檢查懷疑復發性甲狀腺癌。結果：反 覆細胞學檢查疑似轉移性癌病變。但後來，組織切片與頸部磁共振成像(MRI) 均顯示了頸動 脈分叉處的副神經節瘤。結論：頸動脈體瘤與頸部副神經節瘤高度相關，但常因淋巴結或甲 狀腺病變而誤導抑或忽略此診斷的可能性。生成原因可能與胚系突變有關。鑑別診斷的重要 性不僅對治療而且對後續監測都有影響。手術切除是目前第一線的治療方法，但若此腫瘤解 剖位置或大小因素考量亦可考慮放射線治療。頸動脈體瘤有一被遺忘的專有名詞稱為化學受 器瘤(chemodectoma)，以此文介紹給大家。

Differentiating the neck mass between carotid body paraganglioma and recurrent papillary thyroid carcinoma is occasionally difficult. Methods: We report a 66-year-old woman with previous history of papillary thyroid carcinoma, and a 3-cm-sized, non-tender, rapid-growing mass was found over right submandibular region two years later. Recurrent thyroid cancer was suspected initially. Results: Repeated cytology investigations showed metastatic carcinoma. Neck magnetic resonance imaging (MRI) and biopsy finally revealed paraganglioma over carotid bifurcation. Conclusion: Carotid body tumors is highly related with neck paraganglioma, but difficultly indistinguishable from thyroid lesions or metastatic lymphadenopathy. Biopsy is better diagnostic choice than cytology. It might have related with germline mutations. Surgical removal is first-line treatment, and radiotherapy are suggested if unresectable. (J Intern Med Taiwan 2018; 29: 317-322)