Treatment and Mortality in Men with Localized Prostate Cancer: A Population-Based Study in California.

Purpose: To provide patients and physicians with population-based estimates of mortality from prostate cancer or other causes depending upon the primary treatment modality, stratified by patient age, tumor stage and grade.

Methods: We conducted a 10-year competing-risk analysis of 45,440 men diagnosed with clinically localized (T1 or T2) prostate cancer in California during 1995-1998. Information on patient characteristics, primary treatment and cause of death was obtained from the California Cancer Registry.

Results: In this population-based cohort, the most common primary treatment was surgery (40.4%), followed by radiotherapy (29.1%), conservative management (20.8%), and androgen deprivation therapy (ADT) monotherapy (9.8%). Prostate cancer mortality differed significantly (p < 0.0001) across treatment groups among patients <80 years at diagnosis with moderately or poorly differentiated disease; the 10-year disease-specific mortality rates were generally highest for men treated with ADT monotherapy [range: 3.3% (95% CI=0.8-12.5%) to 53.8% (95% CI=34.4-72.2%)], intermediate for men treated with conservative management [range: 1.7% (95% CI=0.7-4.6%) to 30.0% (95% CI=16.2-48.8%] or radiotherapy [range: 3.2% (95% CI=1.8-5.5%) to 18.3% (95% CI=15.1-22.0%)], and lowest for men treated with surgery [range: 1.2% (95% CI=0.8-1.7%) to 11.0% (95% CI=8.4-14.2%)].

Conclusion: The cause-specific mortality estimates provided by this observational study can help patients and physicians better understand the expected long-term outcomes of localized prostate cancer given the initial treatment choice and practice patterns in the general population.