Re: Is a Screening Interval of Every 4 Years for Prostate Cancer Acceptable?

Abstract

In an accompanying editorial, Crawford ( 1 ) critically reviewed our paper ( 2 ) “Interval cancers in prostate cancer screening: comparing 2- and 4-year screening intervals in the European Randomized Study of Screening for Prostate Cancer, Gothenburg and Rotterdam.” We would like to respond to some of his remarks. First, the analysis reported was not done with the intention to defend a 4-year screening interval. At the start of the European Randomized Study of Screening for Prostate Cancer (ERSPC) trial, a 4-year screening interval was chosen based on the current available knowledge on lead time. The only center, and not several centers, as is mentioned in the editorial, that chose differently was the Swedish center in Gothenburg. However, as mentioned previously in the complete overview of the ERSPC in 2003 ( 3 ), the group was awaiting data that would confi rm the correctness of the screening interval of 4 years. The fi rst data that were published with respect to this choice were reassuring ( 4 , 5 ). Our comparative and longer term observations are confi rmatory and will be helpful in developing future screening strategies. Second, we acknowledge that the com