Collection of Cerebrospinal Fluid and Tumor Tissue in Subjects With Metastatic Melanoma and Controls

Inclusion Criteria: 1. Regarding patients with distant metastatic melanoma and established melanoma CNS metastases who are scheduled for craniotomy: * Histologically confirmed, primary cutaneous melanoma, metastatic to the CNS (brain OR spinal cord OR carcinomatous meningitis) based on: * Pathologic confirmation (i.e. prior craniotomy) OR * Radiography (brain MRI or CT scan with intravenous contrast) * Patients must have no contraindications for and be able to undergo lumbar puncture for CSF collection * Hemoglobin level of 8g/dL or higher. This can be drawn on the day of consent, or will be acceptable if documented from a previous visit within the prior 30 days * Subjects must have provided written, informed consent (ICF) prior to any study procedures * Subjects must provide a FFPE tissue block containing a biopsy from the primary site 2. Regarding patients with distant metastatic melanoma and established melanoma CNS metastases who are not having a craniotomy and before they undergo external beam irradiation or stereotactic radiosurgery (patient's and/or neurosurgeon's preference): * Histologically confirmed melanoma (unknown primary, mucosal, ocular are allowed), metastatic to the CNS (brain OR spinal cord OR carcinomatous meningitis) based on * Pathologic confirmation (i.e. prior craniotomy) and/or * Radiography (brain MRI or CT scan with intravenous contrast) * Patients must have no contraindications for and be able to undergo lumbar puncture for CSF collection * Hemoglobin level of 8g/dL or higher. This can be drawn on the day of consent, or will be acceptable if documented from a previous visit within the prior 30 days * Subjects must have provided written ICF prior to any study procedures 3. Regarding patients who have distant metastatic melanoma without radiographically detectable melanoma CNS metastases but are willing to undergo lumbar puncture: * Histologically confirmed melanoma (unknown primary, mucosal, ocular are allowed), * Patients must have no contraindications to lumbar puncture * Hemoglobin level of 8g/dL or higher. This can be drawn on the day of consent, or will be acceptable, if documented from a previous visit within the prior 30 days * Subjects must have provided written ICF prior to any study procedures 4. Regarding healthy volunteers * Patients must have no contraindications to lumbar puncture (see Table 1) * Patient must answer NO to all questions listed in Appendix B * Hemoglobin level of 8g/dL or higher. This can be drawn on the day of consent or will be acceptable if documented from a previous visit within the prior 30 days * Subjects must have provided written, ICF prior to any study procedures Exclusion Criteria: * For study subjects, patients with extradural lesions, i.e. those that originate from the bone (calvarium or vertebrae), will not be considered. * Any significant psychiatric disease, medical intervention, or other conditions, which in the opinion of the Investigators, could impair proper discussion of the informed consent or compromise participation to the clinical trial. * Active systemic treatment for metastatic melanoma within 2 days from the collection of specimens (brain tumor tissue, peripheral blood, CSF). Corticosteroids, other immunosuppressive anti-inflammatory and anti-epileptic medications are allowed. * Patients who have undergone whole brain irradiation therapy within the last 30 days. Therefore neither CNS lesions nor CSF are considered suitable for collection. * Patients with growing CNS lesions at an area that has previously undergone radiosurgery within 3 months prior to enrollment in this study. Therefore CNS tumors from previously irradiated areas using radiosurgery are not considered suitable for collection although CSF is allowed for collection. * Brain abscess. * Patients with new focal findings on neurological examination. * Infected skin over the lumbar puncture needle entry site. * Other conditions that at the opinion of the investigator are contraindicated.