Mediastinal mature cystic teratoma presenting as a painful neck swelling – a case report.

縱膈腔成熟畸胎瘤是成人最常見的生殖腺外生殖細胞瘤(extragonadal germ cell tumor)，且最常見於前縱膈腔；相對地，頸部並不是畸胎瘤的好香位置。我們報告一個罕見病例，為一延伸到頸部之縱膈腔成熟囊性畸胎瘤(mediastinal mature cystic teratoma)。一名28歲女性，頸部呈現漸進性疼痛腫大，且壓迫氣管並將之雄向右方。頸胸電腦斷層攝影顯示一囊性腫塊由前縱膈腔延伸至頸部區域；此病變由多樣性的組織成份構成，包含了軟組織、液體、脂肪及鈣化構造。經外科切除此囊性腫塊後，病理診斷為一成熟囊性畸胎瘤。據我們所知，縱膈腔畸胎瘤很少以頸部腫大為初徵。儘管這是一種少見的表徵，臨床醫師在診治成人頸部腫塊時，應把縱膈腔畸胎瘤列入鑑別診斷。
Mature teratomas of the mediastinum, the most common extragonadal germ cell tumors in adults, usually arise within the anterior mediastinum. In contrast, the neck is an uncommon site for a teratoma. We report an unusual case of mediastinal mature cystic teratoma that extended to the neck. A 28-year-old woman presented with progressive, painful neck swelling, which compressed the trachea and deviated it to the right. Computed tomography (CT) of the chest revealed a cystic mass occupying an area from the anterior mediastinum to the cervical area; the lesion consisted of multiple tissue elements, including soft tissue, fluid, fat and calcification. The cystic mass was resected and the pathological diagnosis was a mature cystic teratoma. To the best of our knowledge, a mediastinal teratoma seldom presents as a neck swelling. Although a rare manifestation, it should be considered in the differential diagnosis of neck masses in adults.