Living Well With Brain Metastases
Recently, I’ve talked to a few newly diagnosed patients with lung cancer who told me that although they were diagnosed at stage IV, they were relieved to learn that the cancer did not spread to their brain because that would have been “the end.” As someone who had 8 small brain lesions when diagnosed in 2013, I agreed that brain metastases are scary to learn about, but definitely not worth considering such a dismal prognosis! Current research estimates that up to 40% of people with lung cancer develop brain metastases at some point.1
First learning about my brain lesions
I remember when I first found out about my brain lesions, my oncologist sent me to consult with a radiation oncologist who told me that the brain can be treated, just like any other organ. This was very comforting for me to hear. By the way, it is important to understand that cancer that spreads to the brain is still considered lung cancer because that is where it originated. It is NOT considered brain cancer!
Since my brain metastases were asymptomatic, I didn’t end up having any form of brain radiation at diagnosis, and instead started targeted therapy treatment, which caused my brain metastases to shrink and disappear with time. Many of the newer types of treatment for lung cancer, such as the latest generations of targeted therapy and immunotherapy medications, can cross the blood-brain barrier and treat lung cancer cells that have spread to the brain.
What is the blood-brain barrier?
What is the blood-brain barrier, sometimes referred to as the BBB? According to the National Cancer Institute, the blood-brain barrier is defined as a “network of blood vessels and tissue that is made up of closely spaced cells and helps keep harmful substances from reaching the brain. The blood-brain barrier lets some substances, such as water, oxygen, carbon dioxide, and general anesthetics, pass into the brain. It also keeps out bacteria and other substances, such as many anticancer drugs.”2
Even if you are not eligible for one of these medications that can pass through the BBB or you develop more brain metastases while on treatment, there are other options. Individual brain metastases can be treated by using stereotactic radiosurgery (SRS) which can deliver high dose, targeted radiation to a brain met in a single session. This is a non-invasive procedure even though it is called “surgery.”
Treatments for brain metastasis
SRS, sometimes referred to as cyberknife or gamma knife, can be used to treat just one brain metastasis or many. There does not appear to be a universal maximum number of brain lesions that can be radiated through SRS; many radiation oncologists are comfortable treating 10 or more, depending on size and location. If I had been exhibiting symptoms from my brain lesions when I was first diagnosed, I would likely have had SRS before starting my targeted therapy, so any symptoms could have been alleviated quickly.
Sometimes brain lesions are large and might require surgery under general anesthesia to remove them. This type of surgery is called a craniotomy and in order to access the tumor, a surgeon will make a small hole in the scalp and the skull. Very small instruments are used called microinstruments so that the cancer can be removed without damaging surrounding tissue. I know quite a few people in the lung cancer community who have had craniotomies and are doing well a number of years later.
Other times, whole brain radiation (WBR) might be recommended. when there are many metastases to the brain. While many patients fear WBR due to concerns about developing memory or cognitive issues, a recent study has found that hippocampal avoidance can significantly reduce potential side effects of WBR. The hippocampus is a part of the brain that contains “stem cells [that] are essential for learning and other cognitive functions, and are especially vulnerable to radiation damage.”3 Radiation can be mapped to avoid this area and be just as effective.
New research is on the horizon
As people are living longer with lung cancer due to improvements in treatments and medications, advances are also occurring in how cancer that spreads to the brain can be treated. There is a lot of research currently going on in this area and lots of hope! It is definitely possible to live well with treated brain metastases.
Do you considered yourself to be a well-informed lung cancer patient?