The Effect of Age on Prostate Cancer Survival

SIMPLE SUMMARY: It is a commonly held belief that elderly men with prostate cancer are less likely to die of their cancer than are younger men because they have a higher risk of dying of another cause. This has impact on prostate screening policies and the decision to offer aggressive treatment. It is not clear to what extent the age of diagnosis and the current age impact on prostate cancer survival. We estimated prostate cancer survival rates and annual mortality rates according to age of diagnosis using data from the SEER program. We identified 116,796 prostate cancer patients diagnosed between 1992 and 1997 and followed them for 20 years. Among men diagnosed before age 70, 17% died of prostate cancer. Among men diagnosed after age 70, 21% died of prostate cancer. For men with low-grade cancers, the annual risk of dying of cancer rose continuously with time since diagnosis and peaked in men 85 years and older. ABSTRACT: It is not clear to what extent the age of diagnosis and the attained age impact on cancer mortality rates in men with newly diagnosed prostate cancer. We estimated annual prostate cancer mortality rates and 20-year survival rates according to the age of diagnosis, race, grade and time since diagnosis using data from the Surveillance, Epidemiology and End-Results (SEER) program. We identified 116,796 prostate cancer patients diagnosed between 1992 and 1997 and followed them for 20 years. There were 21,896 deaths from prostate cancer. We calculated actuarial survival rates and annual prostate cancer mortality rates by age of diagnosis and by tumor grade. The risk of a man dying of prostate cancer was 17% for men diagnosed before age 70 and was 21% for those diagnosed after age 70. The mean annual prostate cancer mortality rate calculated over the 20-year period post-diagnosis was 1.5%. The annual rate increased from 0.9% for those diagnosed below age 60 to 2.1% for those diagnosed above age 70. For men with Gleason score ≥ 7 prostate cancer, the annual prostate cancer mortality rate peaked 2–3 years after diagnosis and then declined. For men diagnosed with Gleason score ≤ 6 prostate cancer, the annual prostate cancer mortality rate continued to rise 20 years after diagnosis and peaked after age 85. This suggests that high-grade prostate cancers are aggressive from the outset, but that low-grade prostate cancers may enter a state of dormancy and reactivate as the patient ages.