Trade-Off between Treatment of Early Prostate Cancer and Incidence of Advanced Prostate Cancer in the Prostate Screening Era

Abstract

Purpose: Prostate specific antigen screening has led to the early detection of prostate cancer. However, there has also been concern about the over diagnosis and overtreatment of patients with indolent cancers. We performed a population based analysis to evaluate the trade-off between excess treatment and prevention.

Materials and methods: We used the CDC (Centers for Disease Control and Prevention) Behavioral Risk Factor Surveillance System survey from 2001 to 2010 to determine rates of prostate specific antigen screening. We used the SEER database to identify all patients diagnosed with prostate cancer from 1988 (pre-prostate specific antigen screening) to 2010. Demographic, staging and treatment data were collected. Cases were classified as early (low/intermediate risk), high risk, node positive or metastatic disease.

Results: Prostate specific antigen screening rates in the last 2 years were 54% for men older than 40 years, including 71% for those older than 60, and did not vary during 2001 to 2010. Comparing 1988 and 2000 to 2010, per 100,000 men the incidence of early prostate cancer increased (61.7 to 113.7), while high risk cancer increased (20.7 to 28.2), node positive cancer decreased (3.7 to 1.8) and metastatic cancer decreased (13.6 to 6.2). The rate of definitive primary treatment (radical prostatectomy or radiation therapy) for men with early cancer increased from 47% to 67% (p <0.001).

Conclusions: Prostate specific antigen screening has led to an additional diagnosis of 5.8 cases of early stage cancer and 3.9 cases receiving treatment for early cancer for every 1 less case of stage IV disease at initial diagnosis. This ratio represents the worst-case scenario for overtreatment and provides a quantitative basis for studying the effect of prostate specific antigen screening.

Keywords: early detection of cancer; medical overuse; prostatic neoplasms.