Masturbating.
From the idea that frequent fapping lessens the risk of prostate cancer in males.
"I was gonna go out last night, but decided to stay at home and fight cancer instead"

"Every time you fight cancer God kills a kitten. What's worse? Cancer or a dead kitten?"
by Kaleidoscope July 2, 2005
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A organization put together by a high school girl and her wonderful mom. The organization makes pillowcases for cancer patients going through chemotherapy.
"Were did you get that sweet pillow case?"
"Pillow Fight 4 Cancer"
by RJ & AH April 20, 2007
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