- Department of Neurosurgery, Ziauddin Medical University, Karachi, Pakistan.
- Department of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
- Department of Neurosurgery, Aga Khan University, Karachi, Pakistan.
Muhammad Waqas Saeed Baqai, Department of Neurosurgery, The Aga Khan University Hospital, Karachi, Pakistan.
DOI:10.25259/SNI_856_2022Copyright: © 2022 Surgical Neurology International This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.
How to cite this article: Saba Saleem Qazi1, Syed Muhammad Ismail Shah2, Muhammad Waqas Saeed Baqai2, Syed Ather Enam3. Primary leptomeningeal melanoma in association with neurocutaneous melanosis: A case report. 25-Nov-2022;13:547
How to cite this URL: Saba Saleem Qazi1, Syed Muhammad Ismail Shah2, Muhammad Waqas Saeed Baqai2, Syed Ather Enam3. Primary leptomeningeal melanoma in association with neurocutaneous melanosis: A case report. 25-Nov-2022;13:547. Available from: https://surgicalneurologyint.com/surgicalint-articles/12027/
Background: Primary melanocytic tumors of the central nervous system accounts for approximately 1% of all melanoma with a peak incidence in the fourth decade. The tumor originates from leptomeningeal melanocytes with a variable degree of belligerence. The proliferation of these melanocytes in large amounts in the dermis and nervous system can raise suspicion of neurocutaneous melanosis (NCM), which is an association between malignant melanoma and the presence of a giant intradermal nevus.
Case Description: We present a case of a 62-year-old South Asian male with a large congenital melanocytic nevus (>20 cm in size) in the left hemifacial, and head region who presented with complaints of a single episode of grand-mal seizure followed by neuropsychiatric symptoms. The patient was thoroughly evaluated both clinically and surgically leading to a rare diagnosis of primary leptomeningeal melanoma of the left temporal lobe. The patient subsequently underwent a neuronavigation guided left temporal craniotomy with gross total resection of the lesion.
Conclusion: Primary leptomeningeal melanoma with a clinical association with NCM is rarely ever reported within the literature. To date, our case is one of the very few instances where such an association is being reported in this age group along with rare neuropsychiatric symptoms.
Keywords: Leptomeningeal melanoma, Neural crest, Neurocutaneous melanosis, Nevus, Primary melanoma, Seizures
Primary central nervous system (CNS) melanomas are malignant melanocytic lesions of the CNS that have a high metastatic potential. They are rare entities and comprise approximately 1% of all cases of melanomas and 0.07% of all brain tumors.[
Primary CNS melanomas are clinically and histologically unique from their cutaneous and retinal counterparts. They demonstrate a benign clinical course.[
A 62-year-old man presented to the emergency room after one episode of a generalized tonic-clonic seizure preceded by an aura of generalized body numbness and right hemiparesis. The family later reported a 3-week history of depressed mood, personality changes, and short-term memory disturbances. The patient had no previous history of seizures, trauma, or any other neurological symptom. He had recently been diagnosed with diabetes mellitus, gastroesophageal reflux disease, and depression. His medications included sitagliptin, metformin, omeprazole, and risperidone.
A detailed physical examination revealed a large congenital melanocytic nevus of more than 20 cm in size. The giant nevus was distributed unilaterally across the left side of the patient’s face and head in a nondermatomal fashion [
Subsequently, brain magnetic resonance imaging (MRI) showed a left temporal lesion in close approximation to the greater wing and petrous portion of the sphenoid bone and measured approximately 37 × 41 × 32 mm [
Preoperative multiplanar and multisequential MRI of the brain. (a) T1 without contrast shows a heterogeneous hyperintense lesion in the left temporal region, (b) T1 with contrast shows further enhancement on contrast administration, (c) T2 shows a hypointense lesion with surrounding hyperintense signals, (d) fluid-attenuated inversion recovery showing edema surrounding lesion, (e) T1 post contrast sagittal, and (f) susceptibility weighted image displaying areas of signal drop out.
A standard left temporal craniotomy was performed during which the tumor was recognized as a darkly pigmented mass in the anteromedial aspect of the left temporal lobe. The tumor was pigmented and firm. It was surrounded by a blood clot of variable ages and was separable from the brain parenchyma. During the procedure, patchy pigmented leptomeninges, islands of pial pigmentation, and perivascular dark arachnoid deposits were also noticed [
Surgical images of densely pigmented leptomeninges of the brain, as seen under the operating microscope. (a and b) Pattern of black multiple discrete clusters of hyper-pigmentation seen over the brain meninges (white arrow). (c) Extensive pigmentation seen as a sheet of dots spread over the leptomeninges (white arrows). (d) Dark, blotched, and pigmented vascularized (white arrows) meninges.
On histopathology, the tumor was revealed as a neoplastic lesion consisting of cells arranged in a solid sheet pattern. The cells individually possessed scanty cytoplasm, an abundance of dark brown pigment coupled with enlarged hyperchromatic round nuclei and prominent nucleoli. Moreover, scattered mitotic activity and reactive glial tissue were also highlighted. Immunohistochemical stains were performed which showed a reactivity pattern consistent with melanoma; Melan A Positive, HMB45 Positive with Ki-67 high proliferative index [
Histopathology of primary leptomeningeal melanoma. (a) Hematoxylin and Eosin stained sections show sheets of medium-sized polygonal cells with moderately pleomorphic nuclei (white arrows) containing dispersed chromatin, macronucleoli, and moderate amounts of eosinophilic cytoplasm. (b) Immunoperoxidase staining for Melan A shows diffuse cytoplasmic staining (white arrows) in tumor cells. (c) Positive staining for Ki-67 (white arrows) is observed.
Postoperatively, a multiplanar and multi sequential MRI of the brain was performed with and without IV gadolinium contrast that showed no post-contrast enhancement or visualization at the site of the previously seen lesion to suggest residual disease. He had a stable postoperative course and was discharged on tapering doses of steroids and anti-epileptics. His case was discussed in our multidisciplinary tumor board meeting and was referred to a medical and radiation oncologist for adjuvant therapy.
Melanocytes are pigment cells in the CNS that are normally localized in the pia mater, high cervical cord, and the frontal part of the medulla oblongata. One theory has described that the pigment cells have a neural crest origin, which eventually develops into mesodermal and neural elements and gives rise to tumors.[
NCM is described as a neuroectodermal dysplasia, characterized by large (>20 cm) or multiple congenital nevi associated with meningeal melanosis or melanoma. The diagnosing criteria also include the following two clinical aspects: no evidence of cutaneous melanoma except in patients in whom the examined areas of the meningeal lesions are histologically benign; no evidence of meningeal melanoma except in patients in whom the examined areas of cutaneous lesions are histologically benign.[
CNS melanomas have a nonuniform histological pattern and are divided into four subtypes; the majority of the tumors are: (1) epithelioid,[
Computed tomography (CT) is of limited diagnostic value for these tumors that produce isodense or hyperdense lesions.[
Treatment options for primary CNS melanoma include surgical excision which carries a good outcome, compared to radiotherapy and chemotherapy, which can be used as adjuvants.[
Malignant manifestation of a primary CNS lesion without metastasis, in juxtaposition to congenital nevi in an older patient, is a unique rarity in clinical neuromedicine. What provides significance to our report is the rare presentation of lesions, late onset of symptoms, importance of neuroimaging, and prompt surgical approach that prevents tumor spread and ensures the longevity of life.
The peculiarity of our case lies in the fact that NCM was discovered late in a 62-year-old patient with neuropsychiatric symptoms, providing an addition to the rarity of such cases found in the literature. The presence of a giant nevus along with a malignancy in the CNS should raise the suspicion of NCM regardless of the age of a patient.
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The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Journal or its management. The information contained in this article should not be considered to be medical advice; patients should consult their own physicians for advice as to their specific medical needs.
1. Adams LC, Böker SM, Bender YY, Fallenberg EM, Wagner M, Buchert R. Assessment of intracranial meningioma-associated calcifications using susceptibility-weighted MRI. J Magn Reson Imaging. 2017. 46: 1177-86
2. Araújo C, Resende C, Pardal F, Brito C. Giant congenital melanocytic nevi and neurocutaneous melanosis. Case Rep Med. 2015. 2015: 545603
3. Balakrishnan R, Porag R, Asif DS, Satter AM, Taufiq M, Gaddam SS. Primary intracranial melanoma with early leptomeningeal spread: A case report and treatment options available. Case Rep Oncol Med. 2015. 2015: 293802
4. Bhandari L, Alapatt J, Govindan A, Sreekumar T. Primary cerebellopontine angle melanoma: A case report and review. Turk Neurosurg. 2012. 22: 469-74
5. Chen L, Zhai L, Al-Kzayer LF, Sarsam SN, Liu T, Alzakar RH. Neurocutaneous melanosis in association with large congenital melanocytic nevi in children: A report of 2 cases with clinical, radiological, and pathogenetic evaluation. Front Neurol. 2019. 10: 79
6. Das K, Nair A, Jaiswal S, Sahu R, Srivastava A, Kumar R. Supratentorial intermediate grade meningeal melanocytoma with intratumoral bleed in the background of neurocutaneous melanosis: Report of an unusual case and review of literature. Asian J Neurosurg. 2017. 12: 98-102
7. de la Fouchardière A, Cabaret O, Pètre J, Aydin S, Leroy A, de Potter P. Primary leptomeningeal melanoma is part of the BAP1-related cancer syndrome. Acta Neuropathol. 2015. 129: 921-3
8. Gupta A, Chacko G, Chacko AG. Prevalence and pattern of leptomeningeal pigmentation in the human brain and its role in the safe surgical excision of extra-axial brain tumors. Neurol India. 2021. 69: 1204-9
9. Jaiswal S, Vij M, Tungria A, Jaiswal AK, Srivastava AK, Behari S. Primary melanocytic tumors of the central nervous system: A neuroradiological and clinicopathological study of five cases and brief review of literature. Neurol India. 2011. 59: 413-9
10. Kadonaga JN, Frieden IJ. Neurocutaneous melanosis: Definition and review of the literature. Am Acad Dermatol. 1991. 24: 747-55
11. Krpan AM, Rakusic Z, Herceg D. Primary leptomeningeal melanomatosis successfully treated with PD-1 inhibitor pembrolizumab: A case report. Medicine. 2020. 99: e22928
12. Mattar MA, Maher H, Zakaria WK. Intracranial malignant melanoma: An Egyptian institute experience. Interdiscip Neurosurg. 2021. 26: 101370
13. Mohapatra A, Choudhury P. An uncommon case of primary leptomeningeal melanoma in a 66-year-old white Caucasian male. Cureus. 2020. 12: e10793
14. Pan Z, Yang G, Wang Y, Yuan T, Gao Y, Dong L. Leptomeningeal metastases from a primary central nervous system melanoma: A case report and literature review. World J Surg Oncol. 2014. 12: 265
15. Quillo-Olvera J, Uribe-Olalde JS, Alcántara-Gómez LA, RejónPérez JD, Palomera-Gómez HG. Primary malignant melanoma of the central nervous system: A diagnostic challenge. Cir Cir. 2015. 83: 129-34
16. Smith AB, Rushing EJ, Smirniotopoulos JG. Pigmented lesions of the central nervous system: Radiologic-pathologic correlation. Radiographics. 2009. 29: 1503-24
17. Sommer L. Generation of melanocytes from neural crest cells. Pigment Cell Melanoma Res. 2011. 24: 411-21
18. Suranagi VV, Maste P, Malur PR. Primary intracranial malignant melanoma: A rare casewith review of literature. Asian J Neurosurg. 2015. 10: 39-41
19. Tanoue N, Ummah FC, Hanada T, Takajo T, Kamil M, Askoro R. Incidentally found primary cerebral malignant melanoma associated with Ota nevus-wide dissemination after an initial phase of slow growth. Hiroshima J Med Sci. 2018. 67: 21-9
20. Wadasadawala T, Trivedi S, Gupta T, Epari S, Jalali R. The diagnostic dilemma of primary central nervous system melanoma. J Clin Neurosci. 2010. 17: 1014-7