Active Smoking Is Associated With Worse Prognosis in Metastatic Renal Cell Carcinoma Patients Treated With Targeted Therapies

Background

Smoking increases the risk of developing renal cell carcinoma (RCC) but the effect of tobacco consumption on survival outcome of patients with metastatic RCC (mRCC) treated with targeted therapies has not been well characterized.

Patients and Methods

The primary outcome was overall survival (OS) and secondary outcome was progression-free survival (PFS). Patients with mRCC were categorized as current, former, and nonsmokers at the time of starting targeted therapy. Smoking data from 1980 patients with mRCC treated with targeted therapy were collected through the International mRCC Database Consortium (IMDC) from 12 international cancer centers.

Results

Although former and nonsmokers had comparable OS times (23.8 vs. 23.4 months; P = .898), current smokers had significantly shorter OS (16.1 months; P < .001) than nonsmokers. Current but not former smoking status was an independent poor prognosis factor (hazard ratio HR], 1.3; P = .002) when adjusted for the IMDC risk criteria. Each pack-year increased the risk of death by 1% (HR, 1.01; P = .036). The duration of first-line therapy response was not different and was 7.7 months versus 7.5 months versus 6.4 months in never, former (P = .609), and current smokers (P = .839), respectively.

Conclusion

Active smoking is associated with diminished OS in mRCC patients treated with targeted therapy agents. However, patients who quit smoking returned to a similar risk of death from RCC compared with patients who never smoked. Smoking cessation should be a counseling priority among mRCC patients receiving targeted agents and smoking should be considered as a confounding factor in major clinical trials.