"Pets provide comfort and relieve stress from cancer." I can agree with this.
Every day when I was in treatment I would hit the "wall" and need to rest and gaze at the crappy day time tv shows (this was before DVR) with glazed eyes, a cup of tea and the cat sitting next to me. He would very patiently snuggle when I wasn't feeling well and absorbed tears and commiserated with me on the state of the world (if his food dish was empty). He is no longer a spring chicken at the ripe old age of 17. He is slowing down.
In the vet's words at his annual check up a few weeks ago, his blood levels are mostly fine but he will probably sleep 97 percent of the time these days. He does.
He greets us at the door each day when we come home (provided he has finished his latest nap) as if the world is coming to an end because he is hungry and needs attention. He is the 5 a.m. cat—his definition of the proper breakfast time. He is adept at sneaking into the bed in the middle of the night and we wake up to find him with his head on the pillows, his body under the blanket, snoring away between us.
Occasionally he acts like 'psycho kitty' and runs around like a crazed kitten on catnip for a few moments but we know he won't be with us forever. We already plan on adopting two cats after he is gone—one for each of us.
Back at my first cancer diagnosis, I lived at home with my parents and we had three cats. One of them, BC, was mine; she stayed there long after I moved out, though I got her while I was in high school. She lived to be 24 and died about 2001. BC was also a comfort as I went through surgery and recovery.
Medical research is finally catching up to what is known by pet owners everywhere:
"... found that pet owners were more likely to survive at least a year after hospitalization for a heart attack or chest pain compared with non-pet owners. Among pet owners, 94 percent survived compared with 72 percent of those who didn’t own a pet."
My non-medical advice is if you are diagnosed with something yucky like cancer, adopt a pet if you don't have one.