Gansler T, et al. - Given previous evidence that smoking might be linked to higher prostate cancer-specific mortality (PCSM) after diagnosis with prostate cancer, researchers assessed the strength of this association and whether it endures after adjustment for stage and Gleason score. Current smoking both before and after diagnosis of prostate cancer was shown to be related to higher PCSM, even after accounting for stage and Gleason score.

Methods

• Men diagnosed with nonmetastatic prostate cancer between enrollment in the Cancer Prevention Study-II Nutrition Cohort in 1992-1993 and June 2013 were analyzed.
• At enrollment, cigarette smoking was self-reported and updated in 1997 and every 2 years thereafter.
• Analyses of pre-diagnosis and post-diagnosis smoking included 9,781 and 9,111 prostate cancer cases, respectively, with vital status follow-up through 2014.

Results

• In analyses of pre-diagnosis smoking and post-diagnosis smoking, 672 and 554 deaths from prostate cancer were reported, respectively.
• Both current smoking before diagnosis (hazard ratio [HR]=1.50; 95% confidence interval [CI]=1.06-2.13) and current smoking after diagnosis (HR=1.71; 95% CI=1.09-2.67) were related to higher PCSM vs never smoking, in multivariable-adjusted Cox proportional hazards regression models, including stage and Gleason score.
• Significantly higher risk of PCSM (HR=1.29; 95% CI=1.04-1.61) was seen in prostate cancer survivors who quit smoking <20 years before diagnosis.