Spinal melanotic schwannoma: a tumour with poor prognosis

• Published in: Histopathology Vol. 35; no. 6; pp. 558 - 566
• Main Authors: VALLAT-DECOUVELAERE, A.-V, WASSEF, M, LOT, G, CATALA, M, MOUSSALAM, M, CARUEL, N, MIKOL, J
• Format: Journal Article
• Language: English
• Published: Oxford, U.K. and Cambridge, USA Blackwell Science Ltd 01.12.1999; Blackwell
• Subjects: Adult; Biological and medical sciences; Biomarkers - analysis; Cauda Equina - pathology; Cell Nucleus - ultrastructure; electron microscopy; Fatal Outcome; Female; Follow-Up Studies; Humans; Immunoenzyme Techniques; Male; malignant tumour; Medical sciences; melanoma; Melanosomes - ultrastructure; melanotic schwannoma; Middle Aged; Neoplasm Recurrence, Local; Neurilemmoma - chemistry; Neurilemmoma - diagnosis; Neurilemmoma - surgery; Neurology; Prognosis; Spinal Neoplasms - chemistry; Spinal Neoplasms - diagnosis; Spinal Neoplasms - surgery; spinal tumour; Tumors of the nervous system. Phacomatoses; Human; Immunohistochemistry; Nervous system diseases; Spinal cord; Relapse; Prognosis; Process variant; Neurinoma; Metastasis; Electron microscopy; Case study; Pathology; Tumor; Adult; Spinal cord disease; Melanin
• ISSN: 0309-0167; 1365-2559
• DOI: 10.1046/j.1365-2559.1999.00786.x

Aim To clarify the prognosis of melanotic schwannoma. This is a rare tumour which is generally considered as a benign lesion, reported in many cases with a short follow‐up only. Methods and results Five cases of spinal melanotic schwannoma were retrospectively studied. The tumours were examined using standard histological, immunohistochemical and ultrastructural methods. No features of malignancy (high mitotic count, atypia or necrosis) were found in the primary tumours. The follow‐up period ranged from 3 to 7 years. Malignant clinical behaviour was clear‐cut in four cases: three patients died from metastases to various sites and one presented several discrete spinal tumours of the same type seven years after the first operation. Only one patient presented no recurrence and was free of disease 6 years after initial diagnosis. The review of 57 cases of the literature (including our cases), showed that 15% of the cases had recurrences and 26.3% were complicated by metastasis. Only 53% of the cases followed for more than 5 years, were free of disease vs. 67.5% of the cases with shorter follow‐up. Twenty additional cases had no follow‐up. Conclusion Appropriate long‐term follow‐up is required for all melanotic schwannomas, as it may recur or metastasize after more than 5 years, even in the absence of overt malignant histological features.