After adjustment , among men without a known family history of prostate cancer , increased body mass index was not associated with a higher risk of prostate cancer ( per one-unit increase in logBMI OR 0.83 , p = 0.54 ) but was significantly associated with a higher risk of high grade prostate cancer ( ieGleason score 7 or greater prostate cancer ) ( OR 2.31 , p = 0.03 ) .