Leptomeningeal Disease: A Patient Guide

Leptomeningeal disease is cancer that has spread into the linings around the brain and spinal cord. The National Cancer Institute describes cancer spreading "to the leptomeninges (the two innermost membranes covering the brain and spinal cord)." NCI also calls this leptomeningeal carcinomatosis. Some teams use a third name, carcinomatous meningitis. All three mean the same thing.

Most cancer that reaches the brain forms a lump. This does not. The cells settle on surfaces and drift in fluid.

Those two thin membranes hold cerebrospinal fluid, or CSF. MedlinePlus calls CSF "a clear, colorless, watery fluid that flows in and around your brain and spinal cord." The fluid moves. Cells move with it.

That is the whole point of the diagnosis. Disease can show up in several places at once. A nerve at the base of the skull. A patch low on the spine. A spot near the back of the brain.

Breast cancer is the most common source, per an NIH StatPearls review, "followed by lung cancer (mainly small cell lung cancer), and melanoma." The American Cancer Society notes that cancer-related meningitis "is mostly seen with leukemias, lymphomas, or very advanced forms of other types of cancer."

Symptoms come from wherever the lining is coated.

From above the neck, StatPearls lists cranial nerve deficits: "diplopia, facial weakness, hearing loss." Diplopia means double vision. Headache is common too. NCI lists, for tumors in the brain, morning headaches, seizures, trouble with vision, hearing or speech, nausea and vomiting, changes in personality or mood, loss of balance, weakness, and unusual sleepiness.

From the spine, StatPearls lists "limb weakness, dermatomal sensory loss, radicular pain, bladder, and bowel dysfunction." Radicular pain shoots along a nerve root, often down one arm or leg. NCI lists, for tumors in the spinal cord, "back pain or pain that spreads from the back towards the arms or legs," bowel or urinary changes, weakness or numbness in the arms or legs, and trouble walking.

Any one of these has other causes. The pattern that worries a team is several of them, in unrelated body parts, arriving over days or a few weeks.

MRI with gadolinium is the main scan. Gadolinium is a contrast dye given through a vein. NCI explains that "gadolinium collects around the cancer cells so they show up brighter."

Here the scan is not hunting a mass. StatPearls describes "leptomeningeal enhancement," meaning the linings themselves light up. Other findings it lists include hydrocephalus, which is fluid backing up inside the brain, and "subependymal nodules/deposits." Along the spine, it describes "patchy enhancement of nerve roots and extramedullary nodules."

Because the disease travels with the fluid, a brain scan alone can miss it. It is fair to ask whether the spine was imaged as well.

The second test is CSF cytology. Cytology means examining cells under a microscope. MedlinePlus lists, among the things a CSF sample is checked for, "whether there are cancerous cells present (CSF cytology)." The lab also counts cells and measures glucose and protein.

The usual way to get a sample is a lumbar puncture, also called a spinal tap. MedlinePlus describes it plainly. You lie on your side or sit up. A thin hollow needle goes "between two vertebrae in your lower spine." Drawing the fluid takes "about five minutes." You may feel a pinch or pressure.

One tap is often not enough. StatPearls reports that "the sensitivity of cytology is 50% to 60% after the first lumbar puncture and approaches 85% to 90% with the second collection." It advises "securing a large volume (10 mL) of CSF for cytology." It also states that "a negative lumbar puncture should be followed by at least 1 additional lumbar puncture, especially if clinical suspicion is high."

So a first clear result does not settle the question.

Headache is the common complaint afterward. MedlinePlus says it "may last for several hours or up to a week or more." Lying on your back for an hour or two afterward may help prevent it. Fluids and caffeinated drinks may help if it starts.

For cancer that has spread to the leptomeninges, NCI lists "chemotherapy (systemic and/or intrathecal)" and adds that "radiation therapy may also be given," along with supportive care.

Intrathecal means the drug goes straight into the spinal fluid. ACS explains that chemo "may be injected right into the fluid that surrounds the brain and spinal cord." That is done "using a lumbar puncture (needle into the back) or through a device called an Ommaya reservoir placed under the scalp." An Ommaya reservoir is a small dome under the skin with a tube running into a fluid space in the brain. It spares repeated needles in the back.

Two supporting medicines come up often. ACS notes that steroids "like dexamethasone, are often used to reduce swelling in the brain." It adds that "anti-seizure medicines may also be used if you have had a seizure."

NCI is direct about the aim. "Often, the goal of treating metastatic cancer is to control it by stopping or slowing its growth." Palliative care runs alongside that work. NCI says it acts "to improve the quality of life by relieving symptoms" and "can be given at any point during treatment for cancer." Asking for it early is reasonable.

• A first-ever seizure. MedlinePlus says to call when "this is the first time the person has had a seizure."
• A seizure lasting more than 2 to 5 minutes. Also call if another seizure starts soon after one ends.
• Someone who "does not awaken or have normal behavior after a seizure."
• New leg weakness, new numbness, trouble walking, or any loss of bladder or bowel control. For someone being treated for a spinal tumor, MedlinePlus says to "go to the emergency room or call 911 or the local emergency number if you develop new symptoms, or your symptoms get worse during the treatment of a spinal tumor." It also says any new or unexplained back pain in a person with cancer should be promptly and thoroughly investigated.

Speed matters here more than people expect. MedlinePlus states it flatly. "Treatment should be given quickly. The more quickly symptoms develop, the sooner treatment is needed to prevent permanent injury."

While a seizure is happening, MedlinePlus first aid applies. Cushion the head. Loosen tight clothing at the neck. Turn the person on their side. Stay with them. Do not hold them down and do not put anything in their mouth.

• Severe back pain that starts suddenly or keeps getting worse. MedlinePlus advises contacting your provider "if you have a history of cancer and develop severe back pain that is sudden or gets worse."
• New double vision, a drooping face, new hearing loss, or slurred speech.
• Headache with vomiting, or a headache that is worst on waking.
• Confusion or sleepiness that a caregiver can see building day to day.
• A headache after a spinal tap that is still there past a week.

• National Cancer Institute — Adult Central Nervous System Tumors Treatment (PDQ) Patient Version
• National Cancer Institute — Metastatic Cancer
• MedlinePlus — CSF analysis
• MedlinePlus — Cerebrospinal Fluid (CSF) Analysis
• MedlinePlus — Spinal tumor
• MedlinePlus — Seizures
• American Cancer Society — Brain Metastases
• NIH StatPearls (NCBI Bookshelf) — Leptomeningeal Carcinomatosis