According to http://www.cancer.org/docroot/RES/content/RES_7_4_Major_Developments_in_Cancer_Research.asp?sitearea=RES :
"...repetitive injury and repair over time may actually influence the pathogenesis of many human cancers. The processes and signals that trigger inflammation needed for the healing and regeneration of injured tissues include angiogenesis (the growth of new blood vessels), cell proliferation, and blocked apoptosis. (Apoptosis, or programmed cell death, is the way the body normally rids itself of damaged cells.) Malignant cells use these same processes and signals to form tumors. So far, these appear to include cancers affecting the liver, esophagus, stomach, large intestine, colon, prostate, pancreas, ovaries, and urinary bladder."
I heard of man who got fatty tumors on several occasions after injuries to the same location, and I heard of a girl who died from a tumor after getting repeatedly beaten by a nun in the location where she got the tumor.
I had a (gonna be honest here) one night stand with an old boyfriend that was rough with my breasts way back in 1976.....Not too long after that I had a lump removed from my right breast. It was like a calcium lump or something like that. (benign) Dr. said it "could" be attributed to the roughness.
Sounds like you could be in danger of being hurt...maybe you should rethink your "play".
Dear sherrilyn, This type of behavior certainly can cause injury to the breast but there is no evidence that such injury would increase the risk of beast cancer. If your husband is causing you unwanted pain, you need to let him know that this is a problem for you.