Singer-songwriter Sheryl Crow announced Tuesday that she has a meningioma – a type of brain tumor that is usually noncancerous.
The breast cancer survivor told CNN the tumor is benign and described it as a "bump in the road."
As word spread about the announcement, Dr. Daniel Pieper, director of neuro-oncology at , offered some insight into this type of tumor. Here's what he had to say:
How common is it?
"They are one of the most common of the intracranial tumors. If you look at studies on cadavers, probably 3 percent of all autopsies will show meningioma," Pieper said. "Meningioma, in and of themselves, account for almost 20 percent of all the brain tumors that we see."
How are they diagnosed?
Meningioma have a "very specific appearance" on an MRI, Pieper said. About 40 percent of the time these tumors are just picked up incidentally and weren't causing any symptoms, and in other cases, patients can experience headaches, seizures or other symptoms that lead them to get an MRI, he said.
What is the process after one is found?
It depends on whether they found it because of symptoms or incidentally, Pieper said. If the patient had a seizure or other event that could be related to the meningioma, doctors may choose to remove the tumor. Oftentimes they are not causing symptoms and a "wait and see" approach is taken. "These are benign in more than 95 percent of cases, rarely are these types of tumors aggressive," he said. "If they see a meningioma but it's not related to her symptoms then the more common scenario is you just wait and see." Regular MRIs would be scheduled to watch for growth and patients would be monitored for new symptoms. "It may take four to five years, even a decade to see any appreciable growth in one of these tumors," he said.
What is the outlook?
"The outlook for meningioma is very good. When we're watching and waiting, a large portion of patients will never even require any intervention," Pieper said. "But those that do, if you completely remove these tumors - and usually there is no reason you cannot - probably between 97 to 98 percent of the time, it's curative - that's it. It's a very gratifying surgery, the patients do extremely well and the long-term results are very good."
What are the symptoms?
There could be no symptoms. In cases that do present with symptoms, the type and severity depends on where the tumor is located. "It's very location-specific," Pieper said. "We hesitate to use the word brain tumor because these are not tumors in the brain. They arise from the covering around the brain. So the symptoms are always due to the location of the tumor." A meningioma near the vision nerve could potentially cause vision loss, or one near the parts of the brain that move the body could cause weakness or seizures, he said.
Why not remove it?
There's no such thing as no-risk brain surgery, Pieper said, and certain places of the brain are more risky than others. "If it's a small tumor, if it's not causing any symptoms, then it's difficult to justify to a patient to take any risk of surgery. If it's growing or symptomatic then the risk is justified."
What are the risk factors?
Cell phones, trauma and other possible risk factors have all been ruled out, Pieper said. Although Crow is a breast cancer survivor, cancer does not increase the risk of developing a meningioma. The only known risk factor is extremely high rates of radiation - like the nuclear power disaster in Chernobyl. "Other than that we've never found an environmental cause," he said.
What signs should people watch out for?
"All of us at one point or another will have a headache, but if somebody starts experiencing chronic headaches, they're not going away, they're lasting for days or they start noticing other symptoms - vision changes, their hearing changes precipitously ... they lose their ability to speak, those are patients that probably do need to undergo testing," Pieper said. "The vast majority of patients that present with such symptoms are never found to have any structural reason behind them," but it's still important to get it checked out, he said.