Primary cerebellopontine angle melanoma: a case report and review

Primary melanomas at the cerebellopontine (CP) angle are extremely rare and considered a diagnostic dilemma. With only 16 prior cases reported so far, there is not enough material in world literature. We report a 29-year-old male who presented with vertigo, headache and features of lower cranial nerve involvement with MRI revealing a melanotic lesion at CP angle. The patient underwent right suboccipital craniectomy and only subtotal excision of the tumor was possible. Histopathologically it turned out to be malignant melanoma. Since a thorough search for any possible primary was futile, it was considered a primary melanoma. Patient was given adjuvant radiotherapy. Ten months later, he presented with weakness and multiple spinal metastases and two months later he succumbed to his disease. We did a comprehensive review of literature about various melanocytic tumors at the CP angle. Pathologically, melanocytic tumors range from benign melanocytomas to malignant melanoma with variable prognosis. The clinical presentation depends upon whether the lesions are diffuse or discrete. Surgery is the primary modality of treatment and the amount of tumor excised is related to the prognosis. We conclude the discussion with a novel classification for melanotic tumors of CNS and the current diagnostic pathway for a melanotic lesion at the CP angle.