October 15, 2015 – Meningiomas

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Meningiomas are a common type of brain tumor that may be related to obesity, a recent study discussed in the inaugural production of Brain Matters, a monthly podcast series with Jon Weingart, a neurosurgeon at Johns Hopkins, concludes.

Program Notes

0:22 The risk of meningioma
1:23 Biological plausibility
2:25 It’s just not a number that you’re shooting for
3:26 Patient having symptoms needs more rapid evaluation
4:25 Hurdle to proposed intervention
5:25 In general no radiation given
6:25 Three grades of meningioma
7:25 Clear association with radiation
8:25 Multidisciplinary approach valuable
9:35 End

Transcript

John Weingart: Hi, I'm John Weingart. I'm a professor of neurosurgery at Johns Hopkins, and we're going to be talking today about issues related to the brain.

Ellizabeth Tracey: I'm Elizabeth. Tracey, welcome to Brain Matters, your look at neurosurgery headlines for the month. This is our first one. This month we're going to start with something that was published about meningiomas.

John Weingart: Today we're going to start out with an article that was published recently talking about the risk of meningioma occurrence in association with weight and physical And this was an article reporting several observational studies, which means they looked at a large population of people, looked at the incidence of certain problems, and one of the problems that they looked at was meningioma. What they found was that in people who had higher weight, and the way they divided that up was BMI, and if they had a BMI of 25 to 29, they had a 20% higher risk for meningioma, and those who were obese, which is defined as a BMI of greater than 30, had about a 50% higher risk of meningioma. They also found that high physical activity levels conferred about a 25% lower risk for meningioma. The physiology behind why this might be isn't clear, and they postulated some issues related to insulin, but there's no clear explanation why this might be the case, but it's an interesting observation and certainly could be motivation for someone to get out and exercise several times a week.

Ellizabeth Tracey: That's in the Journal of Neurology. Help me to understand, you know, we talk an awful lot about this idea of biological plausibility. we look at what people speculate as mechanisms. So how biologically plausible do you find this explanation for an association between higher BMI and a greater likelihood of developing a meningioma?

John Weingart: Well, these things are always multifactorial. Sometimes a higher weight can reflect other health problems, which may play more of a role in the development of certain illnesses or tumors than just the weight itself. So it's a reflection of overall health, and certainly if you're physically active, and you keep your weight down. All health problems seem to be less in that circumstance.

Ellizabeth Tracey: I find it really interesting and tantalizing, and I know you're familiar with this also, this idea of fitness versus fatness and whether one can be overweight and very physically active and still ameliorate many of the deleterious factors relative to obesity. What are your thoughts on that? In this study, of course, they don't talk about that.

John Weingart: I would say that it's just not a number that you're shooting for. So one wouldn't want to starve oneself to get to a lower weight. One would be much better to do regular physical exercise, eat healthy, and then find whatever your natural weight would be.

Ellizabeth Tracey: Let's return then to meningiomas. In your experience, increasing, decreasing, staying the same?

John Weingart: Meningiomas are a problem that are more frequent in older decades of life, so that as people live longer, there will be a higher incidence of meningioma. There are more people alive who are older that could present with one.

Ellizabeth Tracey: Let's talk about presentation. How are most of these found? Are they incidentalomas?

John Weingart: They present in a variety of different ways. Certainly a lot of people get MRI scans for a headache, sinus disease. Oftentimes one will find a small meningioma on an MRI scan. Then there are people who have symptoms, headaches, seizure, weakness, numbness, that leads to them getting an MRI scan where something is found and can be a meningioma at times. Both people need to be evaluated. The patient that's having symptoms needs more rapid evaluation, and a decision needs to be made about intervention and what to do. For somebody that has a meningioma picked up by accident, say, there they need to be seen, but they have time to get information, be educated about what the problem is, think about the decision about whether to have treatment and the timing of that treatment. And that decision depends on size, location. Usually things that are asymptomatic are just monitored with regular MRI scans. The age of the person plays a role. A small meningioma, you're 30 years old, it starts to grow, probably best to have that addressed because the time period over which you're at risk for it to grow is very long. If you're 70 and you have a small meningioma picked up, one can tolerate a little bit of growth, really looking to control the problem for 15, 20 years. There, the hurdle, say, to propose intervention is higher than for the younger person where the risk of growth a much longer period of time.

Ellizabeth Tracey: The meninges, of course, are really kind of interesting in lots of ways. When these tumors arise, which type of tissue do they normally arise from?

John Weingart: Well, they arise from a cell that's normally in the dura. They grow from the lining of the skull, so they're outside the brain, and then they grow and push into the brain and cause symptoms in that way. And they occur everywhere. anywhere in the skull, anywhere where there's dura, they even occur in the spine. And the symptoms they cause are based on the location of the meningioma, and the issues associated for people in terms of treatment are different. So a meningioma on one area of the skull is much different than a meningioma in another area, even though the pathological diagnosis may be exactly the same. But located in the wrong spot, it can be troublesome.

Ellizabeth Tracey: When you're talking about treatment, then, treatment is largely surgical.

John Weingart: Primary treatment is surgery. Surgery to remove the tumor, remove the dural lining that it's growing from.

Ellizabeth Tracey: And not followed up with anything else. No radiation or.

John Weingart: In general, there's no radiation given as part of the standard first-line treatment. People do get radiation for meningiomas. The type of radiation given depends on location, size, and various other factors. As an initial therapy, however, we do favor removal of the tumor. Because it does completely take care of the problem, it also does establish diagnosis. There are different varieties of meningioma there's a Grade One, a Grade Two, and a Grade Three. The Grade One meningioma is the most innocuous, slowest-growing meningioma, and it represents about ninety-five percent of meningiomas. Grade 2 meningioma, what's called an atypical meningioma, represents about 4% of meningiomas. They have a higher incidence of regrowth and recurrence. Sometimes those get radiated after surgery or get radiated sometime in the course of caring for that problem. And then the final meningioma is a grade 3 meningioma, which is a malignant meningioma. It represents 1% or less than 1% of meningiomas. It is not that grade 1 meningiomas become grade 3 meningiomas. Typically, it's a grade 3 meningioma essentially from the start. So people shouldn't be worried that if it's monitored, that it could evolve into a more aggressive tumor. That is not what happens.

Ellizabeth Tracey: What do we know about the etiology of these things?

John Weingart: There's not a lot in terms of the mechanism of why they form understood. They're a little more common in women than in men. They do have estrogen and progesterone receptors on their surface. However, treatments that are aimed at blocking those receptors or interacting with those receptors have not really led to an effective treatment for the problem. There is an association with radiation in meningiomas. So years ago, people who had ringworm were treated with scalp radiation, and they have a much higher incidence of meningioma recurrence. In children that had radiation for leukemia or other childhood cancers, they have a higher incidence of meningiomas developing. So there is a clear association with radiation and meningioma development on a delayed basis. Doesn't mean people should stop getting CT scans or x-rays, but it's something to be aware of.

Ellizabeth Tracey: How many of these things do we see in a year?

John Weingart: They're one of the more frequent brain tumors, certainly here at Hopkins, several hundred a year that have surgery for this problem. It's a problem that needs to be managed to minimize the impact on the person in terms of their quality of life and length of life, but also to not impact their current life unnecessarily. Even when they're small, there should be a good reason to have surgery. So that's why people who have meningioma picked up that's not causing symptoms or the symptoms are not severe, they do have time They get opinions from different people and plan an intervention, a surgery, if it's appropriate, based on their life.

Ellizabeth Tracey: What else would you like to add?

John Weingart: In terms of resecting a meningioma and managing the problem, that a multidisciplinary approach is valuable. Although surgery is the main initial tool, there are a lot of other factors to come into play. And I think there's an advantage to being cared for at a center that does many of these types of surgeries, that has all the resources available to support the patient during their hospital stay and to manage the problem effectively after surgery. We have a multidisciplinary brain tumor group here. We have a meningioma center. These are problems that people are expected to blend right back into their normal life. So they have an operation, three, four weeks later, ideally they're back to work, exercising, doing all their normal things, almost like nothing happened. Since meningiomas generally are not such that you have to drop everything and have surgery tomorrow, there is the opportunity to get second opinions, to travel to a center where it's a frequent problem that they take care of so that you can get thoughts about management, and then the person can make the best decision for themselves about where they want to get their care.

Ellizabeth Tracey: But in general, you would say that the outlook is really quite good.

John Weingart: Oh, absolutely.

Ellizabeth Tracey: Thank you so very much.

John Weingart: Oh, you're very welcome. Look forward to the next month.