SCLC

Lung cancer is one of the most common cancers in the United States, with small cell lung cancer (SCLC) making up about 15 out of every 100 (15%) cases. Like many other types of cancer, lung cancer can spread to the brain and start growing there. This is especially common for SCLC. When this happens, it’s called brain metastases or brain mets. It’s not brain cancer; it’s lung cancer that has spread to the brain.

If you have a diagnosis of SCLC, your healthcare team may discuss the risk of brain metastases, ways to manage that risk, and your treatment options if brain mets occur. It’s important to understand all your choices and openly discuss any questions you have with your healthcare team. This helps you gain the information needed to make informed decisions about your care.

Managing your risk of SCLC brain metastases

There are ways you and your healthcare team can manage your risk of developing SCLC brain mets, including:

• Magnetic resonance imaging (MRI) scans
  Regularly scheduled MRI scans are the best way to detect brain metastases early, when they are easier to treat. MRI scans use strong magnets to create highly detailed images of the brain. These scans can detect very small changes and are usually scheduled every 3 months. If brain mets are seen on your MRI, your healthcare team will discuss treatment options with you.
• MRI scans and prophylactic cranial irradiation (PCI)
  Depending on the stage of SCLC you are diagnosed with, your healthcare team may discuss PCI as an option. PCI is a low-dose radiation treatment given to the whole brain to lower the future risk of brain mets. Its goal is to destroy SCLC cells that may be present in the brain, which are too small to detect on MRI scans. PCI is only an option when your brain MRI shows no signs of cancer. 
  
  Brain mets can still develop even after PCI treatment, and there are risks of long-term side effects with PCI that can impact memory and other thinking skills. Talk to your healthcare team about the benefits and risks of PCI.

Managing SCLC brain metastases

If your MRI shows brain mets, your healthcare team will discuss your treatment options with you. These options depend on the location and number of metastases, when they are found, your previous treatments, and your overall health and personal goals. Treatment for brain mets can include:

• Whole-brain radiation (WBR) delivers radiation to the whole brain. Typically used when there are many brain metastases.
• Stereotactic radiosurgery (SRS) delivers focused beams of radiation to a specific area of the brain. Used when there is a limited number of brain metastases.
• Immunotherapy helps your immune system to find and destroy cancer cells. Some types of immunotherapy drugs can cross into the brain and destroy cancer cells located there.  
• Surgery to remove brain mets may be an option, depending on the location and the number of metastases.
• Clinical trials are research studies done to determine whether a new treatment or combination of treatments is safe and effective. It’s always good to explore clinical trials and discuss your options with your healthcare team. For help finding clinical trials, contact our navigators through our free HelpLine 1-800-298-2436 or email support@go2.org.  

Whole brain radiation (WBR) versus prophylactic cranial radiation (PCI)

Sometimes there is confusion between WBR and PCI. While they may sound similar, they are very different and are used for different reasons. Here’s a breakdown in simple terms.

WBR

• When
  WBR is given when SCLC has already spread to the brain.
• Why
  The goal is to treat cancer that is already there. Radiation covers the entire brain to target both visible tumors and cancer cells that may not show up on scans.
• What to expect
  WBR usually occurs over several treatments, spaced over days or weeks. Common side effects can include fatigue, hair loss, memory or thinking changes, and skin irritation.

PCI

• When
  PCI is given when scans do not detect cancer in the brain. It aims to prevent lung cancer from spreading there. PCI’s goal is to destroy SCLC cells that are too small to be seen on an MRI. 
• Why
  The goal is prevention. By treating the whole brain early, PCI can lower the risk of lung cancer spreading to the brain.
• What to expect
  PCI is usually given in smaller total doses than WBR. Common side effects can be similar, such as fatigue and changes in memory and thinking skills.  

The key difference

• WBR = treatment for brain metastases that already exist
• PCI = prevention, used before metastases appear, low-dose radiation

Summary

Understanding how SCLC can affect the brain and the ways to manage your brain health can help you feel more prepared and confident in your care. Having regular MRI scans and thoughtful discussions with your healthcare team about what is important to you in your care can result in an approach to managing SCLC that is just right for you.

If you’d like to learn more about SCLC, have questions, or need support, please contact our free HelpLine at 1-800-298-2436 or email support@go2.org.

For Sean, running wasn’t just a hobby, it was a way of life. His passion for running connected him with a community, gave him purpose, and helped shape his identity. A 9-time London Marathon finisher and dedicated fundraiser for the UK Teenage Cancer Trust, he has always used running as a way to give back and connect with others. In October 2024, Sean again completed the London Marathon, placing 6th in the male over-55 category with an impressive time of 2 hours, 48 minutes, and 34 seconds. He immediately started training for another race—a 10-miler where he hoped to finish in the UK top 5. True to form, Sean trained very hard. He loves a challenge and never does anything halfway. But during his training runs, he noticed something was off. His energy lagged, and he was struggling to breathe. On race day, he pushed through despite feeling breathless just a mile and a half in. Sean believes “you don’t achieve much in life if you don’t push yourself.” He finished the race in 60 minutes and 23 seconds—a very respectable time by most standards, but far below his usual performance. He was disappointed and blamed overtraining.

When breathing got hard

By New Year’s Eve 2024, Sean was struggling to catch his breath even during short runs and felt unusually weak during light activities like walking his dogs. Believing it might be asthma, he called his doctor and then went to the emergency department, where he had a chest X-ray that revealed an unusual area on his lung. Sean was sent home to wait for the scheduling of a CT scan that would provide more answers. In February 2025, after having the chest CT, Sean learned that he had extensive-stage small cell lung cancer (SCLC) and that it was terminal. The cancer originated in his lungs and had spread to his lymph nodes and pelvic bones. Later, he learned it had also reached his brain. This news devastated Sean, his wife Julie, their children, family, and friends. He had been healthy, fit, and active. Lung cancer had never crossed his mind. The news hit hard. “It felt like all of my dreams had been taken from me,” he said. “Not just running, but the lifestyle, the friendships, the mentoring, the fundraising...” Sean felt like he had lost what made him feel alive and connected. But Sean wasn’t ready to give up.

A powerful send-off—and a new challenge ahead

Before starting treatment, Sean wanted to do one last Park Run—a weekly, community 5K designed to promote health and well-being in the United Kingdom. He wore his England uniform (known as a kit in the UK) and showed up for what would be an unforgettable send-off. An extra 160 people came out to the Park Run that day to support Sean and to run behind him, cheering him on to the finish line. Julie waited at the finish line. Seeing her there meant the world to Sean. At the end of February, Sean began treatment—chemotherapy and immunotherapy, with plans for radiation therapy to his lungs and brain. Unfortunately, he stopped immunotherapy due to side effects, but still, he pressed on.

Finding new purpose

Running had given Sean’s life determination and value for a long time. Without it, he felt lost. Reinventing himself after a cancer diagnosis was frightening, but that began to change in April 2025 when he connected with the Roy Castle Lung Cancer Foundation in the UK. He joined their 30-day walk-a-mile-a-day challenge, and—true to form—he completed it in half the time. Sean’s connection to the Foundation deepened, and he found more ways to be involved, which renewed his sense of purpose and gave him a new path forward. “Having purpose is important,” he said. “It gets me through the hard days, because I know they won’t last forever.” Sean also credits his palliative care team for their support through the Inspire Program, which helps people create new physical or mental challenges to regain control of their lives after a cancer diagnosis. Through this program, Sean has discovered new goals to pursue, including looking forward to seeing the summer solstice sunrise and taking on the challenge of off-road walking.

What keeps him going

To Sean, lung cancer is like running a marathon—there are unexpected obstacles, but the key is to take it a mile at a time. “You can’t think about mile 26 when you’re at mile 1,” he explained. “If you focus on the end, it can break you.” He compares the unpredictability of cancer to the unpredictability of a race and things like rain, cramps, and fatigue. “You don’t know exactly what you’re preparing for, but you prepare anyway. You face it, you fight, and you carry on.” Sean will continue to push himself and challenge his limits, especially on tough days. On good days, he can look back on all he has accomplished and see evidence that cancer hasn’t defeated him.

Advice and reflections after a lung cancer diagnosis

Sean offers some wisdom to others diagnosed with lung cancer:

• Surround yourself with the kind of people who are good for you to be around.

• Stay true to who you are and put your energy into getting better.

• Get out of the house, go for a walk, and change the scenery. Even when it’s difficult.

Sean says, “I’m happy being me,” and feels like he “won at life” because he is making the most of each day and doing his best. When reflecting on what he is grateful for, Sean says he’s especially grateful for his family and how they are all pulling together with the same mindset. One of Sean’s favorite memories is when he received a text from his son after they attended an uphill running group together that read, “I didn’t know you were such a beast, Dad!” And so, Sean continues—1 mile at a time.