Selection Effects May Explain Smoking-related Outcome Differences After Radical Cystectomy

Area of Science:

• Oncology
• Urology
• Public Health

Background:

• The relationship between smoking and mortality in bladder cancer patients post-radical cystectomy remains debated.
• Understanding these outcomes is crucial for patient counseling and treatment strategies.

Purpose of the Study:

• To investigate the impact of current smoking on mortality outcomes in patients who underwent radical cystectomy for bladder cancer.
• To differentiate between bladder cancer-specific mortality and competing mortality in smokers versus nonsmokers.

Main Methods:

• A cohort of 1000 patients undergoing radical cystectomy between 1993 and 2013 was analyzed.
• Proportional hazards models for competing risks were employed to assess mortality predictors.
• Patient characteristics, including smoking status, were compared between groups.

Main Results:

• Current smokers were younger, more frequently male, and had lower BMI and cardiac insufficiency compared to nonsmokers.
• Multivariable analysis indicated current smoking was not a predictor of bladder cancer mortality (HR 0.76, p=0.0687).
• Current smoking was, however, a significant predictor of competing mortality (HR 1.62, p=0.0044).

Conclusions:

• This study did not find evidence of increased bladder cancer mortality among current smokers after radical cystectomy.
• A trend towards lower bladder cancer mortality in smokers was offset by significantly higher competing mortality.
• Selection effects, such as younger age and male predominance in smokers, may explain observed outcome differences.