During the past five years, oncologists have reported an uptick in cancer patients with brain metastases—and it’s not clear why. I explored the impact of this development in my feature story “Breaking the Blood-Brain Barrier” in the Fall 2015 issue of Cancer Today.

Here’s an excerpt:

As the calendar turned to September 2014, Leslie Falduto was feeling at the top of her game. The cancer survivor was running six miles, three days a week. Her oncologist had recently told her she was doing great. And at work, Falduto, a registered nurse, was returning to her favorite post, the neonatal intensive care unit.

Talking about her diagnosis of stage III breast cancer in September 2008 still made her feel anxious. But in the world of cancer, five-year survival is one of those measures that is supposed to make you think, OK, maybe now I can pop the champagne. And Falduto, a mother of two from St. Paul, Texas, has passed that marker the year before. 

But on Sept. 7, when she went to leave the neonatal unit, an odd thing happened. “I couldn’t remember how to open a door,” recalls Falduto, 38. After that, “I couldn’t remember how to walk.” Her right leg started shaking uncontrollably. Then, she passed out. When she awoke, Falduto was in the emergency room, where she was told she’d had a seizure. A neurosurgeon requested an MRI. The scan revealed a tumor the size of a pingpong ball—metastasized breast cancer–deep in her brain.

Read the full story.