A 38-year-old man admitted with headache, left paresis and bilateral sensorineural hearing
loss. Neuroimaging showed a peripheral frontal tumor with hyperintensity on T1WI and bilateral
internal auditory canal (IAC) lesions. (Figures 1, 2 and 3). The presence
of hyperintensity on T1WI, without fat or hemorrhage should direct for lesions containing
melanin11 Ginat DT, Meyers SP. Intracranial lesions with high signal intensity on
T1-weighted MR images: differential diagnosis. Radiographics. 2012;32(2):499-516.
http://dx.doi.org/10.1148/rg.322105761
https://doi.org/10.1148/rg.322105761...
. Resection of the frontal tumor
diagnosed a primary malignant meningeal melanoma with cerebrospinal fluid dissemination once
the patient has no melanocytic lesions outside the CNS. The melanocytic lesions ranges from
melanocytoma to melanoma22 Brat DJ, Giannini C, Scheithauer BW, Burger PC. Primary melanocytic
neoplasms of the central nervous systems. Am J Surg Pathol.
1999;23(7):745-54.,33 Roser F, Nakamura M, Brandis A, Hans V, Vorkapic P, Samii M. Transition from
meningeal melanocytoma to primary cerebral melanoma: case report. J Neurosurg.
2004;101(3):528-31. http://dx.doi.org/10.3171/jns.2004.101.3.0528
https://doi.org/10.3171/jns.2004.101.3.0...
,44 Bydon A, Gutierrez JA, Mahmood A. Meningeal melanocytoma: an aggressive
course for a benign tumor. J Neurooncol. 2003;64(3):259-63.
http://dx.doi.org/10.1023/A:1025628802228
https://doi.org/10.1023/A:1025628802228...
,55 Xie ZY, Hsieh KLC, Tsang YM, Cheung WK, Hsieh CH. Primary leptomeningeal
melanoma. J Clin Neurosci. 2014;21(6):1051-2.
http://dx.doi.org/10.1016/j.jocn.2013.08.018
https://doi.org/10.1016/j.jocn.2013.08.0...
.
Malignant melanoma should be included in the differential diagnosis of neoplastic CSF
dissemination with bilateral IAC lesions mimicking schwannomas in NF2.
MRI showed a frontal peripheral tumor with signal hyperintensity on T1WI (arrowhead) (A), signal hypointensity on T2WI (arrowhead) (B) and enhancement after contrast administration (arrowhead) (C), without hemorrhage on T2 gradient-echo (D).
References
-
1Ginat DT, Meyers SP. Intracranial lesions with high signal intensity on T1-weighted MR images: differential diagnosis. Radiographics. 2012;32(2):499-516. http://dx.doi.org/10.1148/rg.322105761
» https://doi.org/10.1148/rg.322105761 -
2Brat DJ, Giannini C, Scheithauer BW, Burger PC. Primary melanocytic neoplasms of the central nervous systems. Am J Surg Pathol. 1999;23(7):745-54.
-
3Roser F, Nakamura M, Brandis A, Hans V, Vorkapic P, Samii M. Transition from meningeal melanocytoma to primary cerebral melanoma: case report. J Neurosurg. 2004;101(3):528-31. http://dx.doi.org/10.3171/jns.2004.101.3.0528
» https://doi.org/10.3171/jns.2004.101.3.0528 -
4Bydon A, Gutierrez JA, Mahmood A. Meningeal melanocytoma: an aggressive course for a benign tumor. J Neurooncol. 2003;64(3):259-63. http://dx.doi.org/10.1023/A:1025628802228
» https://doi.org/10.1023/A:1025628802228 -
5Xie ZY, Hsieh KLC, Tsang YM, Cheung WK, Hsieh CH. Primary leptomeningeal melanoma. J Clin Neurosci. 2014;21(6):1051-2. http://dx.doi.org/10.1016/j.jocn.2013.08.018
» https://doi.org/10.1016/j.jocn.2013.08.018
Publication Dates
-
Publication in this collection
July 2015
History
-
Received
26 Dec 2014 -
Reviewed
19 Feb 2015 -
Accepted
13 Mar 2015