Yuan Po Hsiang Shawn, Grassner Lukas, Fisher Charles, Dea Nicolas
Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
Department of Neurosurgery, Medical University Innsbruck, Innsbruck, Austria.
J Neurosurg Case Lessons. 2021 Dec 20;2(25):CASE21591. doi: 10.3171/CASE21591.
The diagnosis and management of acinic cell carcinoma (ACC) is often challenging given its similarity to benign tumors, high incidences of late recurrence and distant metastasis, and tendency to be resistant to systemic chemotherapy. A primary parotid ACC resulting in an intradural extramedullary mass has not been reported.
The authors describe such a case that presented as a progressive cervical myelopathy 29 years after initial diagnosis. The tumor, located at the C2-C3 level, infiltrated the dura and contained both extradural and intradural components. This occurred 18 months after the incomplete resection of an extradural metastasis at the same location.
Although intracranial and extradural metastases of various primary malignancies are well reported, secondary spinal intradural malignancies are rare. As a result, there are no established guidelines for the surgical management of intradural extramedullary metastases and prognosis may be difficult to establish. In this case, treatment options were limited because systemic therapy options had been exhausted and repeated radiation to the area was not recommended. We report on this case to highlight the clinical course of a rare local recurrence after spinal metastasis leading to an intradural extramedullary tumor and to show that surgical intervention can lead to improvement of neurological symptoms.
由于腺泡细胞癌（ACC）与良性肿瘤相似，晚期复发和远处转移发生率高，且对全身化疗有耐药倾向，其诊断和治疗往往具有挑战性。原发性腮腺ACC导致硬脊膜内髓外肿块的情况尚未见报道。
作者描述了这样一例病例，在初次诊断29年后表现为进行性颈髓病。肿瘤位于C2 - C3水平，侵犯硬脑膜，包含硬膜外和硬膜内成分。这发生在同一部位硬膜外转移灶不完全切除18个月后。
虽然各种原发性恶性肿瘤的颅内和硬膜外转移已有充分报道，但继发性脊髓硬膜内恶性肿瘤很少见。因此，对于硬脊膜内髓外转移瘤的外科治疗尚无既定指南，预后可能难以确定。在本病例中，治疗选择有限，因为全身治疗方案已用尽，且不建议对该区域进行重复放疗。我们报告此病例以突出脊柱转移后罕见的局部复发导致硬脊膜内髓外肿瘤的临床过程，并表明手术干预可改善神经症状。
