Preliminary tests suggested that the mass was benign or non-cancerous, Sandra recalled; but after Dr. Steven Schneider, a neurosurgeon from North Shore-LIJ Cohen Children’s Medical Center, removed it, doctors found that that wasn’t the case.

Dean was in surgery for more than four hours on Dec. 15, 2011, while his parents waited for him to come out. When Schneider told his mother that the tumor was cancerous, she sank down in her chair in shock and sadness.

“The doctor came out and he had a little smile on his face, but not a big one,” she said. “That’s when he said he had good news and bad news. I just remember sliding down the chair.”

Dean was diagnosed with medulloblastoma, which Sandra explained is a fast-growing cancer that usually affects children younger than her son. She credits the efforts of doctors like Grossman, Schneider and Mark Atlas, of Cohen Children’s Medical Center, for detecting it early and saving Dean’s life.

Although the tumor was gone, Dean still needed treatment to be sure that the cancer hadn’t spread and that it wouldn’t come back.

“You don’t know where the cells are,” Sandra said of the disease. “It’s kind of like a tree that has roots. Even during surgery, if one cell is left or flicks off … you just don’t know.”

The Brownworths decided to give Dean proton radiation treatment, which Sandra said is less invasive than the standard photon treatments. But this form of radiation is used in only a few hospitals around the country, Dean explained, so the family moved into a hotel close to the Massachusetts hospital where he was treated from January to March 2012.

Dean said he was in treatment from Monday through Friday for six weeks, and experienced awful side effects. He was exhausted, vomited constantly and sensed strange smells and tastes that he said he’d rather not remember.

“Whenever they did the radiation, I had this weird taste in my mouth that made me nauseous,” he said. “Even when I think about it today it makes me nauseous.”