An interesting new study released by Keele University’s School of Psychology show's that swearing may increase one's tolerance to pain. The research study was conducted by submerging the subjects hands into ice water and either swearing or not swearing. The test subjects who repeated bad words were able to tolerate their hand in the ice water longer than those who didn't swear.
Interesting but I must point out that a hand dipped in ice water is quite a bit different than the pain most palliative care patients endure. I remember holding an ice cube during my childbirth education classes while practicing lamaze breathing, the ice supposedly mimicking the pain I'd feel during labor. The ice in my hand was bad....actual labor trumped that pain a million times over. I'm pretty sure the same could be said for cancer pain.
That being said, saying a few choice words when you're really in pain can't hurt so why not give it a try?

Swearing may help in the moment…but I always feel worse after the pain subsides and I think about what I said.