Leptomeningeal metastases mean cancer cells have spread to the thin layers of tissue that cover the brain and spinal cord (the leptomeninges). It is also called:

• carcinomatosis meningitis
• leptomeningeal disease
• leptomeningeal carcinomatosis
• neoplastic meningitis

How it happens

Cancer cells can reach the meninges by travelling in the bloodstream from a cancer somewhere else in the body. Or they might spread from a secondary cancer that has already developed in the brain.

A secondary cancer happens when cancer cells break away from the primary cancer and spread to another organ or part of the body. A secondary cancer is also called a metastases.

How common are leptomeningeal metastases?

Between 5 to 10 out of every 100 people (5 to 10%) who have cancer might develop leptomeningeal metastases. It is most common in people with breast or lung cancer, or melanoma skin cancer.

You could talk to your cancer specialist or specialist nurse if you are worried about this.

Symptoms

The cancer cells in the covering of the brain can cause a range of symptoms, including:

• headaches
• changes to your sight such as double vision or loss of sight
• confusion
• weakness
• seizures (fits)
• feeling sick (nausea)
• vomiting
• hearing changes
• facial drooping
• pain in your lower back, legs, or neck
• mental changes such as mood and behaviour
• changes to how you walk
• numbness or weakness of one or both legs and of your bottom
• problems passing urine or stool (poo)

Diagnosis

It can be difficult to diagnose leptomeningeal metastases. It might show up on an MRI scan, or cancer cells might be found in fluid taken from the spine by a lumbar puncture. 

A lumbar puncture is a test to check the fluid that circulates round the brain and spinal cord. The lumbar puncture needle goes through the skin into the small of your back and into the space around the spinal cord. 

Treatment

Some people may not be able to have treatment for their cancer because they are too unwell. So you might have medicine to control any pain other side effects you may be getting. 

Survival

Most people worry about their outlook (prognosis) when they have a secondary cancer. Your individual outlook depends on many factors including whether the cancer has spread to more than one part of your body, how quickly it is growing and how it responds to treatment. 

The aim of treatment for leptomeningeal metastases is to control the growth of the cancer and relieve symptoms. Treatment might be able to control the cancer cells in the meninges for some months, or possibly more than a year with the newer targeted agents for treatment of certain types of lung cancer. 

It is difficult for doctors to predict someone’s outlook and this uncertainty can be hard to deal with.