Carcinomatous meningitis is a complication of late stage cancer. It develops when cancer cells spread to your meninges from other parts of your body. Your meninges are three layers of thin tissue that cover your brain and spinal cord.

Treatment typically focuses on managing your symptoms and maximizing your quality of life.

In this article, we take a closer look at the causes, symptoms, treatments, and outlook for carcinomatous meningitis.

Carcinomatous meningitis is a condition that occurs when cancer cells spread to the membrane surrounding your brain and spinal cord called your meninges. The condition’s name comes from two other medical conditions.

Carcinomatous refers to a specific type of cancer called carcinoma. Carcinoma is the most common type of cancer and makes up about 80 to 90 percent of cancers. It starts in the epithelial cells that line your skin, body cavities, or organs.

Meningitis is a general term that refers to inflammation of the lining of your spinal cord and brain. Potential causes include infectious diseases, some drugs, and cancer.

Carcinomatous meningitis is also sometimes called leptomeningeal metastasis and neoplastic meningitis.

Any type of cancer can cause carcinomatous meningitis, but it’s most commonly a complication of the later stages of:

Symptoms of carcinomatous meningitis can vary significantly depending on where it develops. About 2 percent of people don’t have symptoms at all.

Headache is the most commonly reported symptom and occurs in about 39 percent of people with carcinomatous meningitis.

Other possible symptoms include:

People who develop carcinomatous meningitis usually already have late stage cancer and are likely experiencing severe complications. It’s a good idea to contact your doctor or cancer care team any time you develop new or concerning symptoms.

Carcinomatous meningitis usually develops as a complication of late stage cancer. Cancer that spreads beyond the original site is called metastatic cancer. For many types of cancer, this refers to stage 4.

Metastatic cancer can spread to your lymph nodes and blood vessels and eventually to almost any part of your body.

Carcinomatous meningitis typically develops when cancer cells reach your cerebral spinal fluid. Cerebral spinal fluid circulates through cavities in your brain called ventricles and between the layers of your meninges.

Carcinomatous meningitis can also form as an extension of a brain tumor.

The main risk factors of developing carcinomatous meningitis are:

  • incomplete surgical removal of a secondary brain tumor (metastasis caused by the spread of another cancer)
  • not using radiation therapy after cancer surgery
  • being younger than age 40 and having a secondary brain tumor (metastasis)
  • having late stage cancer

It’s not fully understood why cancer develops in some people and situations and not others. What we do know is that both environmental and genetic factors play a role.

Your genetics are out of your control, and some environmental factors like exposure to pollution may not be entirely in your control either.

However, if cancer is caught in the earlier stages, you generally have a better outlook than with late stage cancer. Regular breast cancer screenings can improve your chances of catching that type of cancer in the early stages.

Here are some general tips to reduce your chances of developing cancer:

  • Exercise and dietary habits. Having obesity raises your risk of developing breast cancer and lung cancer. Exercising regularly and eating a nutrient-dense diet can help you reduce your chances of obesity.
  • Minimizing alcohol consumption. Alcohol consumption increases your risk of breast cancer. Your risk increases the more alcohol you consume.
  • Avoiding smoking. According to the National Cancer Institute, about 90 percent of lung cancers in men and 80 percent in women are attributed to smoking tobacco. Smoking also increases your risk of developing stomach cancer.
  • Barrier methods during sex. People who have HIV have twice the risk of developing lung cancer than others. Using barrier methods during sex can reduce your chance of contracting HIV.
  • Limit ultraviolet (UV) light exposure. Exposure to UV rays increases your chances of developing melanoma. Wearing sunscreen, minimizing direct sun exposure, and avoiding tanning beds reduces your chances of developing this form of cancer.

Carcinomatous meningitis is difficult to treat because it usually occurs together with late stage cancer. This form of cancer has already spread to multiple parts of your body and carries a low chance of survival.

The goal of carcinomatous meningitis treatment is to prolong survival and improve quality of life. Chemotherapy and radiation therapy are commonly used.

Your doctor will consider factors such as the aggressiveness of your tumor, your neurological health, and your Karnofsky performance score (KPS) to determine the best treatment options. Your KPS score is a tool doctors use to predict the length of survival in those with a terminal condition.

Next, we’ll take a closer look at each of the usual treatment options.

Intrathecal chemotherapy

Intrathecal chemotherapy is when doctors inject chemotherapy drugs directly into your cerebral spinal fluid with a spinal tap. It’s often the primary treatment for carcinomatous meningitis.

This type of therapy is used because it allows the chemotherapy drugs to cross the blood-brain barrier. This means it can go from your bloodstream to treat areas of the brain or cerebral spinal fluid.

Traditional chemotherapy and targeted therapy

Traditional chemotherapy drugs may be given to help treat carcinomatous meningitis and underlying cancer. Some types of targeted therapies may also be effective at treating carcinomatous meningitis. Targeted therapies are drug therapies that attack cancer cells and keep them from spreading.

Radiation therapy

Focal radiation therapy is often used to target cancer cells in your meninges. This treatment involves using very precise X-ray beams to kill cancer cells.

Carcinomatous meningitis is usually a complication of late stage cancer, so it often has a poor prognosis. With treatment, the median survival time after diagnosis is 2 to 4 months. Without treatment, the average survival time is around 4 to 6 weeks.

People with breast cancer have a slightly better outlook with a mean survival of 5 to 7 months.

Despite this prognosis, some people do manage to live with carcinomatous meningitis for years, and it’s possible that future treatments will improve its outlook.

A 2016 case study describes a 65-year-old woman who developed carcinomatous meningitis as a complication of breast cancer. She responded well to treatment and lived for another 9 years before passing away due to cancer-related complications.

Carcinomatous meningitis occurs when cancer cells spread to the lining of your brain or spinal cord from other parts of your body. It most often occurs as a complication of late stage cancer.

Treatment usually revolves around managing your symptoms and improving your overall quality of life. Your doctor can help suggest the best treatment options for your particular situation.

It can be difficult to cope with a terminal condition or watch one of your loved ones suffer. The American Cancer Society has a 24/7 helpline where you can speak with a cancer expert who can offer a friendly ear or answer any of your questions.