Melanoma leptomeningeal dissemination following frontoparietal metastasis surgery: Case report and review of the literature

Abstract

We present the case of a patient with a solitary left frontoparietal brain metastasis of melanoma previously treated with surgery. Three months later, the patient was admitted to the emergency room in a confusional state with meningeal signs. A cerebrospinal fluid (CSF) test and magnetic resonance imaging findings suggested a subarachnoid haemorrhage (SAH) and/or meningeal carcinomatosis. The results of a cytological examination of the CSF showed neoplastic epithelial cells consistent with metastatic melanoma cells. Resection of metastatic posterior fossa lesions is often cited as a risk factor for leptomeningeal dissemination, however, when the resection is limited to the anterior fossa, this complication is relatively rare. In contrast, SAH may be a complication of leptomeningeal dissemination and responsible for acute meningeal syndrome. Treatment with high doses of corticoids did not show any improvement, and intrathecal chemotherapy was not possible due to the patient's poor functional status. She succumbed 1 week after admission.

Figure 1

(a and b) MRI of the brain showed a 28-mm sized lesion located in the right frontoparietal area with perilesional edema with subfalcial hernia and compression of the frontal horn of the right lateral ventricle. All images were suggestive of metastasis.

Figure 2

(a and b) CT of the brain showed post-surgical changes and possible post-resection bleeding. (c) The MRI findings showed a right frontal area of malacia related to the previous metastasis surgery with 19×13 mm of transversal and anteroposterior diameters with surrounding changes suggestive of post-radiotherapy gliosis. In T1-weighted image (T1WI) in this malacic area a hyperintensity, as well as sulcus hyperintensity, possibly related to haemorrhage and/or meningeal carcinomatous were noted. The third ventricle was enlarged with periventricular hyperintensity and acute hydrocephaly.

Figure 3

Images of the cytology results of CSF in liquid media (ThinPrep^®) with Papanicolaou staining; magnification, ×63. This image showed a CSF extension with lymphocytosis and isolated enlarged cells, uninucleated or binucleated with a number of prominent nucleoli without nuclear pseudoinclusions; suspect of malignancy and morphologically consistent with melanoma.