Primary melanotic tumors of the nervous system: a consecutive case series

H K Grosshans; A J Huttner; J M Piepmeier; L D Kaulen; R K Fulbright; J M Baehring; P Karschnia

doi:10.1111/ene.14437

Primary melanotic tumors of the nervous system: a consecutive case series

Eur J Neurol. 2020 Nov;27(11):2303-2307. doi: 10.1111/ene.14437. Epub 2020 Aug 10.

Authors

H K Grosshans¹, A J Huttner², J M Piepmeier³, L D Kaulen^{1

4}, R K Fulbright⁵, J M Baehring^{1

3}, P Karschnia^{1

6}

Affiliations

¹ Department of Neurology, Yale School of Medicine, New Haven, CT, USA.
² Department of Pathology, Yale School of Medicine, New Haven, CT, USA.
³ Department of Neurosurgery, Yale School of Medicine, New Haven, CT, USA.
⁴ Department of Neurology, Heidelberg University Hospital, Heidelberg, Germany.
⁵ Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA.
⁶ Department of Neurosurgery, Ludwig-Maximilians-University (LMU), Munich, Germany.

PMID: 32654331
DOI: 10.1111/ene.14437

Abstract

Background and purpose: Primary melanotic tumors of the nervous system (PMTNS) are thought to be an exceedingly rare group of tumors not captured by tumor registries. We aimed to determine relative incidence, clinical presentation, diagnostic findings, patient management, and outcome.

Methods: We retrospectively searched the database of the Section of Neuro-Oncology at the Yale Cancer Center for patients with primary or metastatic melanotic lesions of the nervous system. For patients with PMTNS, we recorded demographic data, clinical presentation, histopathological and imaging findings, therapy, and outcome.

Results: A total of 116 patients with melanotic lesions were identified, including four patients with PMTNS. The relative incidence of PMTNS was therefore calculated as 3.4%. Histology of PMTNS patients revealed melanocytoma in three patients and psammomatous melanotic schwannoma in one patient. Symptoms were non-specific and attributed to tumor mass effect. Magnetic resonance imaging showed hyperintensity on pre-contrast T1-weighted imaging, hypointensity on T2-weighted imaging, and homogenous contrast enhancement in all PMTNS patients. Definitive diagnosis was based on tissue analysis, with detection of melanin-containing cells on conventional histology and S100-positivity on immunohistochemistry. Molecular analysis for GNAQ^Q209L mutation assisted in establishing diagnosis when only small amounts of tissue were available. Aggressive surgical treatment showed favorable outcomes in all cases; radiation therapy was used for residual or relapsed disease. The median follow-up was 7.5 ± 5 years, and all patients were alive on the day of database closure.

Conclusion: Primary melanotic tumors of the nervous system are rare nervous system tumors. Outcome appears excellent, and complete surgical resection may form the basis for favorable outcome. Radiation therapy may represent a therapeutic approach for residual or relapsed disease.

Keywords: brain neoplasms; melanin; nervous system neoplasms; neurology; spinal cord neoplasms.

MeSH terms

Humans
Immunohistochemistry
Magnetic Resonance Imaging
Melanins
Nervous System Neoplasms*
Retrospective Studies

Substances

Melanins