Association of Cigarette Smoking and Smoking Cessation with Biochemical Recurrence of Prostate Cancer in Patients Treated with Radical Prostatectomy

BACKGROUND: Cigarette smoking seems to be associated with prostate cancer (PCa) incidence and mortality.

OBJECTIVE: To elucidate the association between pretreatment smoking status, cumulative smoking exposure, and time since smoking cessation and the risk of biochemical recurrence (BCR) of PCa in patients treated with radical prostatectomy (RP).

DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of 6538 patients with pathologically node-negative PCa treated with RP between 2000 and 2011. Clinicopathologic and smoking variables, including smoking status, number of cigarettes per day (CPD), duration in years, and time since smoking cessation were collected.

INTERVENTION: RP without neoadjuvant therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Univariable and multivariable Cox regression analyses assessed the association between smoking and risk of PCa BCR.

RESULTS AND LIMITATIONS: Of 6538 patients, 2238 (34%), 2086 (32%), and 2214 (34%) were never, former, and current smokers, respectively. Median follow-up for patients not experiencing BCR was 28 mo (interquartile range 14-42). RP Gleason score (p=0.3), extracapsular extension (p=0.2), seminal vesicle invasion (p=0.8), and positive surgical margins (p=0.9) were comparable among the three groups. In multivariable Cox regression analysis, former smokers (hazard ratio [HR] 1.63, 95% confidence interval [CI] 1.30-2.04; p<0.001) and current smokers (HR 1.80, 95% CI 1.45-2.24; p<0.001) had a higher risk of PCa BCR compared with non-smokers. Smoking cessation for ≥10 yr mitigated the risk of BCR in multivariable analyses (HR 0.96, 95% CI 0.68-1.37; p=0.84). In multivariable analysis, no significant association between cumulative smoking exposure and risk of BCR could be detected. Limitations of the study include the retrospective design and potential recall bias regarding smoking history.

CONCLUSION: Smoking seems to be associated with a higher risk of PCa BCR after RP. The effects of smoking appear to be mitigated by ≥10 yr of cessation. Smokers should be counseled regarding the detrimental effects of smoking on PCa prognosis.

PATIENT SUMMARY: We investigated the effect of smoking on the risk of prostate cancer recurrence in patients with treated with surgery. We found that former smokers and current smokers were at higher risk of cancer recurrence compared to patients who never smoked; the detrimental effect of smoking was mitigated after 10 yr or more of smoking cessation. We conclude that smokers should be counseled regarding the detrimental effects on prostate cancer outcomes.