Bill Hobbs, a 69-year-old business operator and sailor from Dartmouth, Mass., had just strapped on a virtual reality headset to get an immersive look at his insides. And what he saw made him holler.

“Is that my kidney?” he said. “I’m going 3D, boys!”

Last May, Hobbs was diagnosed with mesothelioma, a rare and aggressive form of cancer, commonly caused by exposure to asbestos. The headset allowed him see how radiation is very precisely applied to the lining of his lungs. Mesothelioma patients often have a life expectancy of about one year.

“I consider myself an optimist,” Hobbs recounted, with a smile on his face. “My wife keeps wanting to know, ‘Where’d I get it? Where’d I get it?’ I’ve got no idea, and, frankly, I really just don’t care. I’ve got what I’ve got, let’s get on with it.”

Oncologist Dr. Ray Mak and researcher Christopher Williams, of Brigham and Women’s Hospital and the Dana-Farber Cancer Institute in Boston, recently invited Hobbs to take part in an early trial of the virtual reality technology. Physicians can use it to better visualize scans than that offered by traditional imaging techniques, and it may also give patients greater insight into their treatment plan.

Hobbs said he jumped at the chance to “walk through your own body.”

“It doesn’t change anything in the sense of, am I going to get better quicker because now I know something I didn’t know? Not particularly,” he said. “But what it does do is show you what they’re doing and they can tell you why they’re doing it, and that’s a good feeling to have.”