Primary cerebello-pontine angle melanoma: a case report

Arul Ponni,Janaki Gururajachar,Ramani Sowmya,Ritika Harjani,Nirmala Subramanian,Aniruddha Jagannatha,Kirthi Koushik,Ravi Varma

doi:10.14319/ijcto.0203.15

Abstract

Intra-cranial melanomas are commonly metastatic from primary melanoma elsewhere in the body. The primary occurrence of a melanoma in the brain parenchyma is rare. We report a case of 38 year aged woman who presented with deviation of left eye and headache. On imaging, a space occupying lesion was found in the left Cerebello-pontine angle and a preoperative diagnosis of meningioma was made. She underwent left retro-mastoid sub-occipital craniectomy and excision of a black vascular tumor. Histopathological examination revealed a melanoma which was confirmed with Immunohistochemical assay. Search for dermal, mucous and ocular lesions were negative. She received adjuvant radiation to the post- operative tumor bed to 5400cGy in 30 fractions using Intensity Modulated Radiation Therapy technique along with concurrent Temozolomide. She tolerated the treatment well and is symptom free 12 months after treatment. Primary Melanomas are rare lesions of the Cerebello-pontine angle and its radiological features, evaluation and management have been discussed. ------------------- Cite this article as : Ponni A, Jagannatha A, Gururajachar J, Harjani R, Koushik K, Subramanian N, Sowmya R, Varma R. Primary cerebello-pontine angle melanoma: a case report. Int J Cancer Ther Onco l 2014; 2 (3):020315. DOI : 10.14319/ijcto.0203.15

Highlights

Primary melanocytic lesions are rare tumors of Central Nervous System (CNS) with an incidence of 0.9 per 10 million.[1, 2] Though these tumors are seen anywhere along the leptomeningeal axis, they cluster around the Brain stem and high cervical spinal cord because of high aggregation of melanocytes in the leptomeninges at these locations.[3,4,5] The melanotic cells originate either from embryonic neuroectodermal cell rests or from the pial sheaths of the vasculature in the CNS.[6]
Focal tumors range from benign melanocytomas to malignant melanomas
We reported a case of rare primary CNS malignant melanoma at Cerebello-pontine (CP) angle, managed successfully with gross total resection (GTR) and adjuvant radiotherapy along with concomitant Temozolomide

Summary

Introduction

Primary melanocytic lesions are rare tumors of Central Nervous System (CNS) with an incidence of 0.9 per 10 million.[1, 2] Though these tumors are seen anywhere along the leptomeningeal axis, they cluster around the Brain stem and high cervical spinal cord because of high aggregation of melanocytes in the leptomeninges at these locations.[3,4,5] The melanotic cells originate either from embryonic neuroectodermal cell rests or from the pial sheaths of the vasculature in the CNS.[6]. The lesion was compressing left Cerebellar Hemisphere It was uniformly isointense on T1W images with a peripheral rim of hyper intensity, isointense on T2W images with a focal area of hyper intensity in the adjacent Cerebellum and showed homogeneous contrast enhancement. With these features, a preoperative diagnosis of left CP angle Meningioma was made. Post-operative contrast MRI showed complete tumor excision and normal posterior fossa (Figure 5). The final diagnosis was a primary (nodular) malignant melanoma of Left CP angle with cerebellar infiltration. She received adjuvant radiation in conventional fractionation to a total dose of 5400 cGy in 30 fractions, 180cGy per fraction, five days per week to the tumor bed on 6MV Linear Accelerator using Intensity Modulated Radiation Therapy (IMRT- Figure 6A, B) technique. One year follow-up MRI of the brain showed no recurrent mass (Figure 8)

Discussion

Findings

Conclusion