Enomoto Toshiyuki, Aoki Mikiko, Miyagawa Ken, Matsumoto Juntaro, Kobayashi Hiromasa, Takeuchi Toranoshin, Abe Hiroshi, Nonaka Masani, Sakata Toshifumi, Inoue Tooru, Nabeshima Kazuki
Department of Neurosurgery, Faculty of Medicine Fukuoka University, Fukuoka, Japan.
Department of Pathology, Faculty of Medicine Fukuoka University, Fukuoka, Japan.
World Neurosurg. 2020 Aug;140:332-337. doi: 10.1016/j.wneu.2020.05.180. Epub 2020 May 27.
Salivary duct carcinoma (SDC) is a rare parotid tumor that often develops as a rapidly growing mass with a poor prognosis. It has a high rate of distant metastases, sometimes with infiltration along nerves. We describe a case of SDC that originated outside the cranium and extended into the cranium along the path of the facial nerve.
A 74-year-old man underwent magnetic resonance imaging at a local hospital, which revealed a tumor in the left internal acoustic canal; the patient was referred to our department. A left facial schwannoma was suspected, and magnetic resonance imaging was performed again 6 months later. Rapid tumor growth was confirmed, and the tumor was resected. The tumor displayed atypical epithelial cells with comedo necrosis and cribriform structure and was diagnosed as SDC. All residual intracranial tumors were removed using the middle fossa approach. The tumor, which was considered to be a primary tumor, was found near the stylomastoid foramen, and it was removed with the parotid gland. Five months after the initial surgery, metastasis to the trigeminal nerve was observed, and this was removed using a retrosigmoid approach, followed by radiation therapy.
All 4 surgical specimens of this case were presented, and the path of tumor progression was examined in detail. Although the primary lesion was small, intracranial invasion along the facial nerve occurred. SDC should be considered as a tumor that can extend into the cranium, even with a small primary lesion.
涎腺导管癌（SDC）是一种罕见的腮腺肿瘤，通常表现为生长迅速的肿块，预后较差。其远处转移率高，有时会沿神经浸润。我们描述了一例起源于颅外并沿面神经路径延伸至颅内的涎腺导管癌病例。
一名74岁男性在当地医院接受磁共振成像检查，结果显示左侧内耳道有肿瘤；该患者被转诊至我科。怀疑为左侧面神经鞘瘤，6个月后再次进行磁共振成像检查。证实肿瘤生长迅速，遂行肿瘤切除术。肿瘤显示有非典型上皮细胞伴粉刺样坏死和筛状结构，被诊断为涎腺导管癌。使用中颅窝入路切除了所有残留的颅内肿瘤。被认为是原发肿瘤的肿块在茎乳孔附近被发现，并与腮腺一并切除。初次手术后5个月，观察到三叉神经转移，采用乙状窦后入路将其切除，随后进行放射治疗。
展示了该病例的所有4个手术标本，并详细检查了肿瘤的进展路径。尽管原发灶较小，但肿瘤沿面神经发生了颅内侵犯。即使原发灶较小，涎腺导管癌也应被视为一种可延伸至颅内的肿瘤。
