Fifteen-year Outcomes Following Conservative Management Among Men Aged 65 Years or Older with Localized Prostate Cancer

Abstract

Background: To understand the threat posed by localized prostate cancer and the potential impact of surgery or radiation, patients and healthcare providers require information on long-term outcomes following conservative management.

Objective: To describe 15-yr survival outcomes and cancer therapy utilization among men 65 years and older managed conservatively for newly diagnosed localized prostate cancer.

Design, settings, and participants: This is a population-based cohort study with participants living in predefined geographic areas covered by the Surveillance, Epidemiology, and End Results program. The study includes 31 137 Medicare patients aged ≥65 yr diagnosed with localized prostate cancer in 1992-2009 who initially received conservative management (no surgery, radiotherapy, cryotherapy, or androgen deprivation therapy [ADT]). All patients were followed until death or December 31, 2009 (for prostate cancer-specific mortality [PCSM]) and December 31, 2011 (for overall mortality).

Outcome measurements and statistical analysis: Competing-risk analyses were used to examine PCSM, overall mortality, and utilization of cancer therapies.

Results and limitations: The 15-yr risk of PCSM for men aged 65-74 yr diagnosed with screening-detected prostate cancer was 5.7% (95% confidence interval [CI] 3.7-8.0%) for T1c Gleason 5-7 and 22% (95% CI 16-35%) for Gleason 8-10 disease. After 15 yr of follow-up, 24% (95% CI 21-27%) of men aged 65-74 yr with screening-detected Gleason 5-7 cancer received ADT. The corresponding result for men with Gleason 8-10 cancer was 38% (95% CI 32-44%). The major study limitations are the lack of data for men aged <65 yr and detailed clinical information associated with secondary cancer therapy.

Conclusions: The 15-yr outcomes following conservative management of newly diagnosed Gleason 5-7 prostate cancer among men aged ≥65 yr are excellent. Men with Gleason 8-10 disease managed conservatively face a significant risk of PCSM.

Patient summary: We examined the long-term survival outcomes for a large group of patients diagnosed with localized prostate cancer who did not have surgery, radiotherapy, cryotherapy, or androgen deprivation therapy in the first 6 mo after cancer diagnosis. We found that the 15-yr disease-specific survival is excellent for men diagnosed with Gleason 5-7 disease. The data support conservative management as a reasonable choice for elderly patients with low-grade localized prostate cancer.

Keywords: Population-based study; Prostatic neoplasm; Survival.

Fig. 1

Competing risks of death by age at diagnosis, cancer stage, and grade. Dark shading indicates prostate cancer–specific mortality and light shading mortality due to competing causes; nonshaded areas represent the probability of being alive. Results for well-differentiated disease are not shown because estimates were unstable due to limited sample sizes.