Lung cancer is the No. 1 cause of cancer-related death in the United States, and it’s the most common cancer diagnosis behind prostate cancer for males and breast cancer in females. Lung cancer — or cancer in general — can spread to other parts of the body, a process called metastasis. The brain is one of the most common sites for lung cancer to metastasize.

Read on to learn about life expectancy and outlook for someone diagnosed with lung cancer that has spread to the brain, symptoms, and how lung cancer tumors in the brain are diagnosed and treated.

How Does Lung Cancer End up in the Brain?

For people with cancer, healthy cells in their bodies are locked in a tug-of-war with cancer cells. A person’s body tries to destroy the cancer as quickly as possible, and cancer cells try to grow and spread as much as possible.

Cancer that starts in the lung can spread via the blood and lymph fluid, usually first to the lymph nodes and then beyond. This metastasis process allows cancer cells to travel to other parts of the body. Lung cancer that has spread to distant parts of the body is considered stage 4, the most advanced stage. (Lung cancer stages are sometimes written with Roman numerals, e.g., “stage IV” instead of “stage 4.”)

Normally, thick walls around the blood vessels in the brain keep most molecules and cells out. Called the blood-brain barrier, it protects the central nervous system (the brain and spinal cord). Lung cancer cells can break down this barrier, developing ways to dodge and escape a person’s immune system.

Life Expectancy and Survival Rates

There is currently no cure for metastatic lung cancer. However, advancements in research and cancer treatment continue to improve survival times and quality of life for people living with lung cancer that has metastasized to the brain.

Previously, lung cancer with multiple brain metastasis was considered a hopeless diagnosis, but new targeted therapies have changed that. For example, a decade ago, many people with lung cancer tumors containing a protein called ALK were expected to survive six to nine months. Research from 2019 found that for people with stage 4 ALK-positive non-small cell lung cancer (NSCLC) who received proper treatment, the median overall survival rate was around 6.8 years. This means half of all people with the diagnosis who receive the right treatment lived at least 6.8 years.

The prognosis for metastatic lung cancer that has spread to the brain varies based on a lot of factors. It’s important not to get discouraged by survival rates you might read online. They’re only averages of the millions of people around the world who have dealt with lung cancer and brain metastases — each of whom, like you, is in a unique scenario. Some people survive the “average” amount of time, but there are also many people who survive much longer.

It’s also important to remain hopeful as you or your loved one go through this journey. In fact, studies show that people who have high resiliency and greater social and emotional support report a higher quality of life during treatment than people who don’t. Having regular follow-ups with your doctor and health care team will also give you the best outcome for your specific situation.

Symptoms of Lung Cancer Spread to the Brain

Depending where in the brain they have spread, the resulting tumors can cause a variety of symptoms.

Headache

One of the main symptoms of brain metastases is headaches. About half of people with brain metastases will have headache as their first noticeable symptom, and most will have a headache at some point.

Your skull is a closed, tight space that houses the brain. Because of the skull’s fixed size, any tumors in the brain put additional pressure on the skull, causing headaches as a result. Cancer-related headaches are often morning headaches. They may be worse when lying down and get worse over time. They may come along with nausea and vomiting.

Members of MyLungCancerTeam often discuss headaches as a symptom of lung cancer spreading to the brain. After receiving treatment for brain metastases, one member asked, “When do the headaches go away?”

Another member, on their way to get test results wrote, “I am a little worried about the brain scan since I’ve been having more headaches lately.”

Seizures

If you experience a seizure for the first time and you’re living with lung cancer, it may be a warning sign of possible metastases to the brain.

Some members of my MyLungCancerTeam have experienced seizures related to lung cancer that has spread to the brain. One explained, “I had a seizure. … A few minutes after finishing breakfast my hand started to jerk, then my face turned up to the left. The whole incident lasted about 30 seconds.”

Another member shared that the first indication their lung cancer had spread was a seizure: “My lung cancer moved to my brain three-and-a-half years ago. I never knew anything was wrong until I had a seizure.”

Loss of Normal Functions

The brain governs a wide range of functions — including the ability to think clearly, speak, and move arms and legs. Any of these functions can be affected when a tumor invades the brain.

Common neurological symptoms that might be associated with a brain tumor include:

• Changes in mental function
• Changes in mood or personality
• Speech problems
• Loss of balance or coordination
• Changes in one’s ability to feel touch
• Weakness in one’s arms or legs

Members of MyLungCancerTeam have related a variety of these kinds of symptoms. “I’ve been struggling with lower back pain and major leg weakness,” one shared. “So the doctor ordered an MRI of my brain.”

Another added, “I just had an MRI due to balance. They found five small metastatic spots on my brain.”

Diagnosis of Lung Cancer That Has Spread to the Brain

If you have lung cancer and report potential symptoms of brain metastasis, your doctor may recommend imaging scans. This helps doctors see if there is a metastatic brain tumor and, if so, where it is and how far the lung cancer has spread to other parts of the body. These include positron emission tomography (PET) scans, computed tomography (CT) scans, and MRI scans of the brain and body.

The initial diagnosis of brain metastases from lung cancer may also involve a biopsy of any lesions found on brain scans. In a biopsy, a tiny piece of the tissue is removed and analyzed under a microscope for diagnosis. A biopsy can tell your oncologist if your lesion is metastatic cancer that spread from the lungs (or elsewhere) or if it started in the brain itself.

Scans may also be taken of the rest of the body to gauge the cancer’s spread. This will help your doctor determine the right treatment options for you and provide a realistic outlook for your treatment.

Treatment and Decision-Making for Brain Metastases

Treatment of brain metastases usually involves a combination of:

• Medication — Pain relievers and other medications to help control epilepsy and reduce swelling related to the tumor
• Radiation — Either whole-brain radiation therapy or stereotactic radiosurgery, which uses targeted “beams” of radiation
• Neurosurgery — Surgical removal of the tumor, used in certain situations

Your type of treatment or combination of treatments depends on several factors:

• Your overall health
• The specific type of lung cancer you have
• How well your lung cancer is controlled overall
• The number and locations of your brain tumor or tumors.

Some people wonder about prophylactic (preventive) brain radiation for lung cancer. However, this is not usually recommended.

Overall Health and Function

How well you’re doing overall is important in deciding what treatment plan will work best for you. Doctors use many scales to assess your overall function and health. Going through treatment is difficult and takes a toll on the body, especially with the side effects of medications, radiation, and surgery. While giving everyone the greatest number of years possible is important, so is making sure that those years are comfortable and free of pain and suffering.

Type of Lung Cancer

Treatment will differ by the exact type of lung cancer involved. There are two broad categories of lung cancer: small cell lung cancer (SCLC) and non-small cell lung cancer.

Standard treatment for SCLC cell lung cancer doesn’t always include surgery. This type of lung cancer often responds well to radiation or chemotherapy. NSCLCs, such as adenocarcinoma, respond less favorably to chemotherapy or radiation.

Biopsy results can also reveal which genes and targets are tagged to your specific type of cancer. Many chemotherapy drugs have been designed to target specific proteins that cancer cells might have, like EGFR or ALK. These are called targeted therapies.

Treatments called immunotherapies can train your immune system to better eliminate cancer cells from your body. Many newer research studies and clinical trials are focused on immunotherapy.

Number and Location of Brain Metastases

If a person has only one large tumor, surgery may help. However, if there are multiple tumors or the tumors are very small, surgery is generally avoided. In this case, whole-brain radiation therapy or stereotactic radiosurgery may be better choices.

Some parts of the brain directly control vital functions like breathing, consciousness, or our ability to speak and see. Because open surgery in these areas may damage these key functions, your oncology team may want to avoid surgery in these areas of the brain when possible.

Talk With Others Who Understand

On MyLungCancerTeam — the social network for people with lung cancer and their loved ones — more than 12,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Have you been diagnosed with lung cancer metastases in your brain? Have you had treatments for them? Share your experience in the comments below, or start a conversation by posting on your Activities page.