Meningeal melanocytoma

Abstract

We report a fatal case of meningeal melanocytoma in the cerebello-pontine angle in a 10-year-old child. This case exemplifies the vascular nature of these lesions even with minimal vascular blush on angiography. An updated literature search is presented, the results of which highlight the need for close follow-up and adjuvant treatment following subtotal resection.

MR Imaging Findings of the Intraspinal Meningeal Melanocytoma: Correlation with Histopathologic Findings

“…13,14 To date, approximately 4 cases with multifocal lesions have been reported. 15, 16 Ali et al 6 considered multifocal MM as a distinct pathologic entity that seems to portend an aggressive clinical course and a poor prognosis, even when malignant pathologic features are absent. In our study, 2 patients with multifocal lesions did not show malignant pathologic features compared with those with solitary lesions, but 1 patient with multifocal lesions developed malignant melanoma and died of metastasis 13 months after surgery.…”

“…5 It is typically hyperintense on T1WI and hypointense on T2WI and enhances homogeneously with gadolinium. 10,[16][17][18][19] The characteristic signal intensity of MM is thought to be caused by the paramagnetic susceptibility effect of the melanin pigment or hemorrhagic foci; hence, its radiologic signal intensity is variable and inconstant. 16,19,20 However, differences in duration, different amounts of melanin, and hemorrhage in malignant melanoma may influence the signal intensity of tumor cells on MR imaging.…”

“…10,[16][17][18][19] The characteristic signal intensity of MM is thought to be caused by the paramagnetic susceptibility effect of the melanin pigment or hemorrhagic foci; hence, its radiologic signal intensity is variable and inconstant. 16,19,20 However, differences in duration, different amounts of melanin, and hemorrhage in malignant melanoma may influence the signal intensity of tumor cells on MR imaging. 9,14,19,20 Amelanotic melanoma and melanoma without hemorrhage are iso-or hypointense on T1WI and moderately hyperintense on T2WI.…”

Immunohistochemical characteristics of melanoma

“…angiomyolipomas, lymphangiomyomatosis and pulmonary Ôsugar' tumors), sweat gland tumors, meningeal melanocytomas, clear cell sarcoma of the tendons and aponeuroses, some ovarian steroid cell tumors and some breast cancers as well as renal cell carcinomas with a t(6,11)(p21;q12) translocation. 8,14,[18][19][20][21][22][23][24][25] Many of these tumors are fortunately histologically distinct from melanomas. There has been a report that HMB45 also stains pheochromocytomas, but this finding has not been corroborated.…”

Molecular histology on the diagnostic cutting edge between malignant melanomas and cutaneous melanocytomas (Review)

“…Some of these lie grouped together (agminate type) and potentially recur after removal of a solitary lesion (23). The term melanocytoma is similarly used in other fields of human pathology (leptomeninges, eye) and animal pathology (skin) for distinguishing peculiar and usually benign melanocytic neoplasms (24,25).…”