病史A 39-year-old man with progressive gait unsteadiness for 2 months39岁男性,步态不稳并逐渐加重2月余。
图例Thoracic spine MRI reveals an intradural extramedullary mass lesion causing spinal cord compression at the T9-T10 level (arrow), which is hyperintense on sagittal T1WI (A) and hypointense on T2WI (B). Sagittal (C) and coronal (D) postcontrast T1WI demonstrates a solid, oval-shaped mass with enhancement. There is no dural tail of enhancement.胸椎MRI示T9-T10水平髓外硬膜囊下肿块,T1WI呈稍高信号,T2WI呈稍低信号。增强扫描矢状位及冠状位示病灶呈卵圆形实性肿块,明显强化。未见“硬膜尾征”显示。
H&E stain (E) shows tumor cells containing large amounts of melanin pigment (x100). Immunohistochemical examination (F) reveals tumor cells staining diffusely positive with HMB-45, an antibody specific for melanocytic tumors (x200).
HE染色示肿瘤内含有大量的黑色素成分(×100)。免疫组化示黑色素瘤特异性抗体HMB-45呈弥漫阳性(×200)。
Spinal Meningeal Melanocytoma脊膜黑色素细胞瘤
背景
- Meningeal melanocytoma is a rare tumor arising from melanocytes of the leptomeninges, which usually has benign histologic features and good prognosis. However, there is potential for local recurrence, malignant transformation, and distant metastasis.脊膜黑色素细胞瘤是一种起源于软脊膜黑色素细胞的罕见肿瘤,通常具有良性组织学特点,预后较好。但肿瘤可以有局部复发、恶变、远处转移。
- Meningeal melanocytoma has only been reported in the posterior fossa and spine, and can be intra-axial (intramedullary) or extra-axial (extramedullary) in location.文献报道中,脑脊膜黑色素细胞瘤仅发生于后颅凹和脊柱,可以发生于脑内(髓内)或脑外(髓外)。
- In the spine, these lesions are most commonly intradural extramedullary.在脊柱,病变大部分位于髓外硬膜下。
临床表现Most patients present clinically with a slow, progressive history of myeloradiculopathy.患者通常表现为缓慢渐进性的脊髓神经根症状。
影像诊断要点MRI shows well-defined, round, or ovoid masses, which are typically hyperintense on T1-weighted sequences (melanin), hypointense on T2-weighted sequences, and enhance with gadolinium.MRI通常表现为圆形或卵圆形肿块,边界清楚,T1WI呈高信号,T2WI呈低信号,增强扫描明显强化。
鉴别诊断
- Meningioma 脊膜瘤
- Pigmented schwannoma 黑色素性神经鞘瘤
- Melanoma 黑色素瘤
治疗要点Complete resection plus radiotherapy. Follow-up imaging is needed to monitor for tumor recurrence.手术全切加放疗。术后需定期检查,观察肿瘤有无复发。