Change of tumour characteristics and treatment over time in both arms of the European Randomized study of Screening for Prostate Cancer

Abstract

Objective: To evaluate a change in tumour characteristics and applied treatments over time in the control arm of all centres of the European Randomized study of Screening for Prostate Cancer (ERSPC) and to compare this with similar data of the screening arm.

Methods: Between 1993 and 2003, 182,160 men, aged 50-74 years, were randomised to the screening arm (N=82,816) and the control arm (N=99,184). Men in the screening arm were offered Prostate Specific Antigen (PSA) testing every 4 years whilst men in the control arm received usual care. Tumour characteristics and treatment were evaluated in all men diagnosed with prostate cancer up to December 2006 or the third screening round. Data on the control arm were divided into 3 periods: 1994-1998, 1999-2002 and 2003-2006.

Results: Tumour characteristics were more favourable over time in both the control and the screening arm, with especially increasing proportions of T1C tumours with 29% in 1994-1998 versus 50% in 2003-2006 and 48% at the initial screening round versus 75% at the third screening round, respectively. Tumour characteristics observed in the last period of the control arm were comparable to tumour characteristics in the initial screening round. In the control arm, treatment changed over time with surgery as the most common treatment in the entire observed period, but almost doubling of expectant management and the combination of hormone therapy and radiotherapy over time. In the initial screening round, surgery was the most common treatment (42%), changing over time to expectant management as the most frequently applied treatment in the third screening round (33%).

Conclusion: Tumour characteristics in the control arm became more favourable over time and show similarity with prostate cancer cases detected at the initial screening round. The most prominent change in treatment over time was an increase of application of expectant management in both arms of the ERSPC. These observations reflect an increasing rate of opportunistic testing over time in men randomised to the control arm.