Actress Kate Walsh is well known for her role as a Doctor Addison Montgomery on the long running television series Grey’s Anatomy. However, Walsh recently went from being a fictional doctor to a real life patient with a medical issue of her own. On September 18, she announced publicly that she had a brain tumor removed in 2015. She had a brain tumor known as a meningioma, is a tumor arising from the lining that surrounds the brain and spinal cord. She had it removed three days after she was first diagnosed. Fortunately, the tumor was benign.

Walsh first thought she was suffering from exhaustion, because she was always tired. When she started having other symptoms, such as lack of concentration, problems with balance, and headaches, she decided to go to a neurologist for tests.

“I would reach for words or thoughts, and I just couldn’t finish them,” Walsh said in an interview with CNN.

The doctor noticed that the right side of her face was drooping.

“I had to really advocate, because they don’t hand out MRIs so easily, but I got an MRI and thank God I did, because it turned out I had a very sizable brain tumor in my left frontal lobe,” Walsh said. “And three days later I was in surgery having it removed.”

A meningioma tumor is more common in women, and is usually benign and slow growing.  Walsh said that her tumor could have been in her brain for anywhere from two to 10 years.  There are about 27,000 reported cases of meningioma per year, according to data from the Central Brain Tumor Registry in the United States. The tumors can cause seizures, but Walsh was lucky not to have had any. These tumors are not as aggressive as other brain cancers, which can double in size every couple of weeks. U.S. Senator John McCain was recently diagnosed with one of these more aggressive cancers.

Depending on the size of the tumor, most meningiomas are removed surgically and no further treatment is necessary. However, if the tumor is small, a doctor may recommend watching and waiting to see if it grows. In rare cases where malignant cells are found, or if the tumor is close to something like the brain stem, radiation can be used to treat the tumor.

Other celebrities such as Sheryl Crow, Mary Tyler Moore and Maria Menounos have gone public with their own stories of having a meningioma tumor. Walsh says that she decided to go public with her story in order to raise awareness of this tumor, which affects mostly women. She has teamed up with her former Grey’s Anatomy co-star Patrick Dempsey for an ad campaign that encourages people to get annual checkups.

“I was so relieved to know that it was something [that I could fix],” said Walsh. “Trust your instincts. Trust your body.”