Smoking is known to be a risk factor for many tumors, but it seems to be controversial in prostate cancer (PCa), and even some studies have shown that current smoking status reduces the risk of PCa occurrence. Also biochemical recurrence after radical PCa surgery is an important issue for PCa patients. So what is the relationship between smoking and biochemical recurrence? Recently, Rieken et al. from Weill Cornell Medical College explored the correlation between biochemical recurrence and preoperative smoking status, cumulative smoking exposure, and time to quit smoking in patients after radical PCa resection. The results found that smoking increased the risk of biochemical recurrence of PCa, although quitting for more than 10 years reduced this risk. The article was published in a recent issue of European Urology. The retrospective study included a total of 6538 patients from 2000 to 2011 who had undergone radical resection for PCa (negative for lymph node metastases) and were not treated with neoadjuvant chemotherapy. Study metrics included clinicopathological and smoking-related variables such as smoking status, number of cigarettes smoked per day (CPD), duration, and time to quit. The primary endpoint was the occurrence of biochemical relapse, i.e., PSA >0.2 ng/ml at two consecutive follow-up visits. The analysis showed that 2238 (34%), 2086 (32%) and 2214 (34%) of the 6538 patients were never, former and current smokers, respectively, and the patients were divided into three groups on this basis. The median follow-up time without biochemical relapse was 28 months. There were no significant differences in the Gleason score, extracapsular infiltration, seminal vesicle infiltration, and positive surgical margins among the three groups. Five-year biochemical recurrence-free survival rates were 90%, 84%, and 83% in the three groups, respectively. The risk of biochemical recurrence of PCa was higher in former and current smokers compared to non-smokers. However, quitting smoking for more than 10 years reduced the risk of biochemical recurrence. In addition, multivariate analysis found no significant correlation between cumulative smoking exposure and risk of biochemical recurrence. These results suggest that smoking status is strongly associated with biochemical recurrence after PCa radical surgery, with the risk of biochemical recurrence almost twice as high in former and current smokers as in nonsmokers. The adverse effect of smoking on biochemical recurrence appears to be mitigated when smoking cessation occurs for more than 10 years. This is a wake-up call for smoking patients that smokers need to be fully aware of the impact of smoking on PCa prognosis and for physicians to take a broader role in the health management of the smoking population.