It’s normal for the diagnosis of a brain tumor to inspire of fear, anger and confusion. And it will for the estimated
70,000 people who will be diagnosed with a primary brain tumor—a tumor that begins in the brain—and the countless more who will be diagnosed with a
metastatic brain tumor—a tumor that begins as cancer in another part of the body and spreads to the brain—each year. Acquiring the correct information both from your doctor and your own research is the key to finding a way through those initial
feelings and deciding on a course of treatment.
As a part of National Brain Tumor Awareness Month,
Ryan Merrell, MD, Neuro-Oncologist at NorthShore, answers our questions on brain tumors, both primary and metastatic, from current treatment options and on-going clinical trials at NorthShore, to potential causes of brain cancer and more:
Often the first question after a brain cancer diagnosis is what the chances of survival are. What would be your answer to that question for patients with a metastatic brain tumor?
Survival in metastatic tumors depends heavily on the type of tumor. For example, many patients with metastases, which are tumors that spread from other areas of the body, from breast cancer have better survival than patients with metastases from melanoma.
Also, within a particular tumor type, some subtypes do better than others. For example, certain mutations associated with non-small cell lung cancer often have better outcomes. Also, the extent of disease in the body is very important. If a patient has a
cancer that has not spread to multiple organs, survival odds are better. We see some patients with metastatic brain tumors with long-term survival.
If you are diagnosed with brain cancer, would it be better to see a neuro-oncologist than an oncologist?
Most neuro-oncologists train in neurology first and then specialize in neuro-oncology. They are often better trained to tackle the specific neurologic challenges of brain tumors. That doesn’t mean that a medical oncologist (oncologist) is not capable. In fact,
many medical oncologists at top centers specialize in taking care of brain tumors. I would make your decision more on how many brain tumor patients the physician sees per year and if that is a substantial portion of their practice.
Are there minimally invasive surgery options available for brain tumors or is a craniotomy still the only way to remove a tumor?
This is a provocative question. My sense is that the future of brain tumor surgery is moving towards less invasive procedures. For now, open craniotomies (big surgeries) are the gold standard. However, neurosurgical techniques are becoming more and
more refined. For example, we are now using an endoscopic technique that allows the surgeon to make a smaller incision and disrupt less of the normal brain during surgery. The idea is that this will lead to shorter recovery times and better long-term outcomes.
We also have a minimally invasive thermal laser ablation technique that we are currently using to treat metastatic tumors that develop delayed swelling after radiation (radiation necrosis). This technique allows a patient to go home the day after the procedure.
We are looking to expand this procedure to the direct treatment of tumors as well.
What makes a brain tumor inoperable? If you are told you have an inoperable tumor, what can be done?
The location of the tumor in the brain is important. For example, tumors in the brainstem, motor cortex and deep brain structures (basal ganglia, thalamus) cannot be removed safely without harming the patient. These areas can be biopsied.
Other brain locations are difficult but can be operated on by skilled neurosurgeons. I highly recommend getting a second opinion if you are told that a tumor is inoperable because it may be that the neurosurgeon you are seeing is not comfortable doing that
surgery. At NorthShore, we are aggressive at operating on any tumor location, but are also very cautious not to undertake a surgery that would cause permanent neurologic harm to a patient.
Is rehab always necessary after brain surgery?
Not always. This depends a lot on the age of the patient, the presence of other medical problems and the location of the tumor. For example, an 80-year-old patient is more likely need rehab than a 40-year-old patient. A tumor that is near the motor
cortex, which could cause weakness on one side of the body, would also likely require the patient to undergo rehab after surgery. We do, however, have many patients that go directly home after surgery. We have an outstanding inpatient rehab unit at Evanston
that allows us to directly transfer patients to the unit a few days after surgery if necessary.
After surgery to remove a tumor, what is the typical treatment that follows?
This depends highly on the type of tumor, metastatic or primary, and covers a wide spectrum. Most tumors will require either radiation and/or chemotherapy after surgery. There are some malignant tumors—low-grade gliomas, for example—that can be watched after
surgery. At a minimum, all malignant tumors require close follow-up with serial MRI scans after surgery.
What factors should be considered in deciding when to discontinue chemotherapy?
That depends a lot on the context. Stopping chemotherapy when the tumor is not growing or when it’s growing. For example, in glioblastoma, there is no evidence that giving more than 12 cycles of the chemotherapy drug temozolomide leads to better outcomes when
the tumor is not growing. When a tumor is growing and we have exhausted all treatment options and the patient can no longer tolerate treatment, we have to make the difficult decision to stop the chemotherapy. Of course, the patient's decision is the most important.
The patient has the right to stop chemotherapy at any time.
What percentage of malignant brain tumors in the US are caused by environmental factors vs. genetic factors or both?
The simple answer is that this is unknown. There are no known environmental risk factors for malignant brain tumors. The cell phone studies have not been revealing. It’s rare that malignant brain tumors occur in families. Even having a first-degree relative
(sibling, child or parent) with a brain tumor doesn’t put a patient at increased risk. There are rare tumor syndromes associated with brain tumors. At NorthShore, we’re involved with an international study that studies both genetic and environmental risk factors
for brain tumors. We hope to uncover some answers in the next few years.
So do cell phones cause brain tumors?
The answer is probably not. There have been several cell phone studies but none have shown definitively one way or another if cell phones are a risk factor. Many of my colleagues and I believe that the exposure a cell phone emits is theoretically too small
to cause the development of a brain tumor, but, like many things in the brain tumor world, the jury is still out. It’s most likely fine to talk on cell phones with regard to brain tumor risk.
What are some of the best clinical trials for brain tumors? Are there any at NorthShore?
Unfortunately, there is no “best” clinical trial. Nobody in the world can make that claim. That is why they are trials. We participate in several clinical trials, the majority of which are for glioblastoma. Current clinical trials for glioblastoma involve targeted
therapies and immunotherapies. We have both and have phase I, II and III trials.
Find out more information on clinical trials at NorthShore
How do you decide which clinical trial is the best one for you?
This is a tough question. There is no way for anyone to know which trial is better than another. If a particular trial appeared to be producing home run results, we all would steer patients to that trial. That has not happened yet.
I tell patients to choose trials based on the science behind them. Does a trial seem scientifically more interesting than another? Also, what does the trial require in terms of time commitment? Does the trial require weekly visits and a lot of travel time?
Some patients prefer open label trials over randomized trials. Some patients prefer trials that allow crossover at the end, meaning that they can get the study drug if they were in the placebo group initially.
What is the brain tumor vaccine? Who does this work for?
Most vaccine therapies are designed for high-grade gliomas, and usually for glioblastoma (the highest grade glioma). We currently have three trials involving vaccines therapies for glioblastoma with two different types of vaccines.
On a national level, there are many different types of vaccine trials. A vaccine is just a term that implies immunotherapy, meaning that you are trying to engineer the immune system to mount a response against the brain tumor in a specific way.
What are your thoughts on the use of medical marijuana to help treat the symptoms that arise from having a brain tumor?
Like many physicians, I’m on the fence here. I think there are some symptoms—pain and nausea—that would clearly could benefit from medical marijuana; however, often, we are able to treat those symptoms by more traditional methods. I am open to the idea of using
medical marijuana in select patients. We are waiting to hear from the state of Illinois and NorthShore regarding the logistics of how we will be able to prescribe it.
Dr. Merrell will be speaking on the subject of Malignant/High Grade Tumors: Update in Treatment and Care at American Brain Tumor Association’s Patient & Family Conference on Saturday, July 26th in Chicago. More information