The initial study looked at 15 dogs, giving three groups of five dogs different dosages. "We looked to see how long the tumor would take to spread as well as how long the dog lived," said Brown.
Typically, a dog with the disease survives "anywhere from three weeks to three months" without removing the spleen, according to Brown. But in the study, the dogs that received the highest doses "doubled" the survival time, she said.
So far, the mushroom therapy, looking at blood counts and chemical screens, has shown no side effects. "We follow their baseline every month until they died and we didn't see any abnormalities," Brown said.
The way these dog tumors spread is comparable to how they metastasize in humans, according to Brown.
"We believe if we can definitely show this can decrease the spread of tumors, it will be applicable in other kinds of tumors, not just hemangiosarcomas in dogs, cats and people," she said.
Meanwhile, Gillman said he is thrilled Reuben, though slowed down, is doing well.
"We go to the beach and he runs in to the ocean and we give him ice cream sundaes," he said. "We go to the dog park and he gets chased around by his friends."
"He's doing well and has put on weight," he said. "He looks like the handsome good-looking boy again."
Knowing that Reuben's participation may help other dogs and people, "makes me feel great," said Gillman.
"I am proud to be involved," he said. "Reuben's always been a giver. We call him the Buddha of dogs."