The value of radiotherapy for the treatment of meningeal melanocytoma

Background: Meningeal melanocytoma is described as rare benign lesion with a high risk of recurrence, There are no well-substantiated treatment recommendations in the literature. Only case reports have been published by now. Patients and Methods: In 1997 a patient was irradiated for a recurrent spinal meningeal metanocytoma and 2 years later for brain metastases indicating malignant transformation. This case gave rise to a literature review for therapeutic options. All sufficiently documented cases published since 1972, when the term meningeal metanocytoma was established, were evaluated. Based on published and on original data recurrence and overall survival rates up to 5 years were calculated for three different therapeutic approaches, namely complete tumor resection, incomplete resection with subsequent radiotherapy, and incomplete resection atone. Statistical evaluation was performed using the x(2) test and Kaptan-Meier-analysis. Results: 53 patients (including our patient) met selection criteria. Complete tumor resection was superior to incomplete resection atone with lower recurrence (4-38% versus 50-92%) and better overall survival rates (86-95% versus 30-58%). After incomplete resection radiotherapy seemed to improve prognosis (recurrence 15-45%, overall survival 91-92%). Between complete resection and incomplete resection plus radiotherapy no significant differences were observed. Conclusions: For meningeal melanocytoma complete resection must be regarded as the best of the modalities compared. After incomplete resection radiotherapy should be considered, although a specific radiotherapeutic regimen cannot be recommended at present. However, for multiple cranial or spinal lesions total cranial irradiation or craniospinal irradiation is indicated.