Leptomeningeal Disease

Nov. 14, 2025

This page was reviewed under our medical and editorial policy by Keng Lam, M.D., assistant clinical professor, Department of Medical Oncology & Therapeutics Research, City of Hope^® Cancer Center Duarte.

Leptomeningeal disease is a rare form of metastatic cancer. The condition is sometimes also called leptomeningeal carcinomatosis, carcinomatosis meningitis, neoplastic meningitis or lepto.

About 110,000 people are diagnosed with leptomeningeal disease every year. This number has been increasing, however. One key reason for this may be better and more accurate diagnosis.

What is Leptomeningeal Disease?

Leptomeningeal disease develops when cancer that started elsewhere in the body spreads to the leptomeninges, which are thin layers of tissue surrounding the brain and the spinal cord and spinal fluid. It affects around 5% to 8% of people with solid tumor cancers and 5% to 15% of patients with blood cancers.

What Are the Leptomeninges?

Between the skull and the brain are several layers of tissue called meninges that protect both the brain and the central nervous system. The first layer is called the dura mater. Beneath this, there are two further layers called the pia mater and the arachnoid, between which there is a cavity filled with cerebrospinal fluid. Together, the pia mater and the arachnoid form the leptomeninges.

Leptomeningeal disease affects only these two layers or the cerebrospinal fluid between them and not the brain or spinal cord itself. If cancer spreads from elsewhere in the body to the brain, this is referred to as either metastatic brain cancer or brain metastases.

Which Cancers Spread Most Frequently?

Patients with almost any type of primary cancer are at risk of developing leptomeningeal disease. However, studies have found that certain cancer types put patients at a higher-than-average risk of the disease.

• About 5% to 10% of women with metastatic breast cancer develop leptomeningeal disease, in particular women with HER2+ or triple negative breast cancer.
• Between 6% and 30% of melanoma patients may develop leptomeningeal disease.
• Between 9% and 25% of lung cancer patients may develop leptomeningeal disease. 

Researchers are continuing to investigate which cancer types are most strongly linked with leptomeningeal metastasis.

Leptomeningeal Disease Symptoms

Some common symptoms of leptomeningeal disease include:

• Headaches that are new and/or don’t go away
• Nausea or vomiting
• Feeling dizzy or light-headed
• Problems with urinary continence
• Changes to eyesight, hearing, memory
• Issues coordinating body movements or walking
• Changes in mood or behavior
• Numbness or paralysis in the face
• Weakness or numbness in the arms or legs
• Seizures

How Are Leptomeningeal Metastases Diagnosed?

There are two main methods cancer doctors use to diagnose leptomeningeal disease. Patients may undergo one or both of these procedures.

• A lumbar puncture (also called a spinal tap) may be used to take a sample of cerebrospinal fluid from around the spine. This sample is then tested in a lab for signs of cancer.
• Magnetic resonance imaging (MRI) may be used to take images of the brain or spinal cord. Specialist doctors will then use the MRI images to look for leptomeningeal disease tumors.

It may be overwhelming to get a leptomeningeal disease diagnosis, but the care team is there to answer any questions the patient may have. “The number one question I get from my patients is whether there are any treatment options available to them,” says Keng Lam, M.D., a neuro-oncologist at City of Hope in the Los Angeles area. “I think the first important step would be to make sure we arrive at the correct diagnosis, which could mean additional tests. Sometimes, patients may be told they have leptomeningeal disease and it may turn out to be not true.”

Second, Dr. Lam says, an interdisciplinary team, which includes neuro-oncologists, medical oncologists, radiation oncologists and neurosurgeons, work with the patient to offer the best personalized option for his or her specific situation.

Leptomeningeal Disease Treatment

Because leptomeningeal disease is a type of stage 4 cancer and is located in a hard-to-reach part of the body, it can be difficult to treat. Treatment is also highly individualized and may differ depending on factors such as the location of the patient’s primary cancer, their overall health and what symptoms they are experiencing. Some common approaches to treating leptomeningeal disease are:

• Radiation therapy, which uses powerful beams of radiation to target and destroy cancer cells.
• Intrathecal chemotherapy, which delivers chemotherapy drugs directly into a patient’s cerebrospinal fluid.
• Certain kinds of targeted therapies, which target a patient’s cancer on a molecular or cellular level.

The goals of treating leptomeningeal disease also depend on the patient’s unique situation. For some, the goal of treatment may be to control the disease. For those who are facing a terminal diagnosis, treating leptomeningeal disease may help manage the symptoms and effects of the condition and improve their quality of life.

Prognosis

The prognosis for patients with leptomeningeal disease is often poor, with average survival rates for solid tumors that spread being 2 to 6 months from the point of diagnosis. However, with early detection and consultation, many patients can exceed that survival rate. Researchers are also continuing to develop new therapies for the disease that may help improve the prognosis for patients with the disease.