Treatment options for localized prostate cancer: quality-adjusted life years and the effects of lead-time

Abstract

Objectives: The purposes of this study were to estimate the difference in quality-adjusted life-years between conservative management and prostatectomy or radiotherapy (RT) by clinical Gleason score (2 to 4, 5 to 6, 7, and 8 to 10) for patients aged 55 years and older with clinically localized prostate cancer and to adjust for and explore the effects of lead-time. For localized prostate cancer, it is not known whether treatment (prostatectomy or RT) results in longer quality-adjusted survival than conservative management. Observed survival benefits after treatment may be biased by the lead-time resulting from early diagnosis with prostate-specific antigen screening.

Methods: A Markov simulation was developed, and transition probabilities were derived from a review of published studies. Utility weights were measured in male volunteers older than 60 years. Estimates of disease progression during conservative management were adjusted for lead-time. Sensitivity analyses were performed on all parameters (including estimates for lead-time).

Results: For Gleason score 2 to 4 cancer, conservative management yielded the greatest number of quality-adjusted life-years. For Gleason score 5 to 6 cancer, any of the options appeared beneficial, depending on the estimates for disease progression. For Gleason score 7 to 10 cancer, prostatectomy and RT resulted in more quality-adjusted life-years than conservative management; with a lead-time adjustment of greater than 10 years, the outcomes with conservative management and prostatectomy were similar. The choice between prostatectomy and RT was sensitive to estimates of disease progression after treatment.

Conclusions: Conservative management is a reasonable option for Gleason score 2 to 4 cancer and for some patients with Gleason score 5 to 6 cancer. Prostatectomy or RT is recommended for Gleason score 7 to 10 cancer. The survival benefits after treatment were not explained by the lead-time alone.