Cervical Spinal Meningeal Melanocytoma Presenting as Intracranial Superficial Siderosis

Abstract

Meningeal melanocytoma is a rare pigmented tumor of the leptomeningeal melanocytes. This rare entity results in diagnostic difficulty in imaging unless clinical and histopathology correlation is performed. In this case report, we describe a case of meningeal melanocytoma of the cervical region presenting with superficial siderosis. Extensive neuroradiological examination is necessary to locate the source of the bleeding in such patients. Usually, the patient will be cured by the complete surgical excision of the lesion.

Figure 1

Axial sections of the brain: (a) T1 weighted and (b) T2 weighted images showing mild effacement of the sulci. Positive phase shift and blooming along the sulcal spaces (arrow heads) on (c) phase and (d) MIP (susceptibility weighted) images suggestive of superficial siderosis.

Figure 2

Sagittal sections of the cervical vertebral column: (a) T2 weighted and (b) T1 weighted images showing an intradural extramedullary mass which appears hypointense on T2 weighted image and hyperintense on T1 weighted image. (c) Postcontrast fat saturated T1 weighted and (d) subtracted contrast image showing mild peripheral heterogeneous enhancement of the tumor since the true enhancement pattern was obscured by the strong T1 hyperintensity of the mass on unenhanced images.

Figure 3

Axial images of the cervical vertebral column: (a) T1 weighted and (b) T2 weighted images showing an intradural extramedullary mass (arrow) occupying the anterior intradural space, compressing and displacing the spinal cord posteriorly. (c) On postcontrast fat saturated T1 weighted images the lesion shows peripheral heterogeneous enhancement.

Figure 4

PET image showing moderately FDG avid intradural mass lesion (arrow).

Figure 5

Histopathological examination. (a) Diffusely pigmented tumor with peritheliomatous arrangement which obscured the cytological details (H and E 40x). (b) After bleaching, tumor had pleomorphic round to oval nuclei with inconspicuous nucleoli and moderate amount of cytoplasm (H and E 40x). (c) Tumor on higher magnification had mild nuclear pleomorphism, moderate to abundant cytoplasm with few containing blackish brown pigment. No significant increase in mitosis was seen (H and E 200x).