What is Primary Melanocytic Tumour of the CNS?
Primary Melanocytic Tumour of the central nervous system (CNS) are rare tumours arising from melanocytes in the thin layers surrounding the brain and spinal cord. These tumours range from slow-growing melanocytomas, which have a favourable prognosis, to aggressive melanomas, which spread rapidly. Early diagnosis and treatment are crucial for managing malignant cases.
Causes
These tumours are linked to genetic mutations, particularly in the BRAF and NRAS genes, which drive uncontrolled tumour growth in aggressive cases. They may also be associated with neurocutaneous melanosis, a condition where congenital melanocytic nevi (large birthmarks) coexist with leptomeningeal melanocytic tumours, increasing the risk of malignancy.
Signs and Symptoms
- Headaches
- Seizures
- Neurological deficits
- Hydrocephalus (in some cases)
Diagnosis
- MRI with contrast is the primary imaging tool for detecting melanotic CNS tumours and distinguishing them from other brain abnormalities.
- Biopsy and genetic testing confirm malignancy and identify mutations (BRAF, NRAS) that help guide treatment.
Treatment
- Surgery is the first-line treatment for tumours that can be safely removed.
- Radiation therapy may follow surgery for cases where complete removal isn’t possible.
- Targeted therapy (BRAF inhibitors) can slow progression in malignant cases with BRAF mutations.
Prognosis
- Melanocytomas (benign cases): Good survival rates.
- Malignant melanomas: Poor prognosis due to aggressive growth and spread.
You can help us with your donation:
Without a Ribbon is a charity that works hard to aid those who suffer from rare cancers. You can help our cause in a variety of ways: