Journal of the National Cancer Institute Advance Access originally published online on January 29, 2008
JNCI Journal of the National Cancer Institute 2008 100(3):222; doi:10.1093/jnci/djm293
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
© The Author 2008. Published by Oxford University Press.
CORRESPONDENCE |
Re: Is a Screening Interval of Every 4 Years for Prostate Cancer Acceptable?
Affiliation of authors: Department of Urology, Erasmus Medical Centre, Rotterdam, The Netherlands
Correspondence to: Monique J. Roobol, PhD, Department of Urology, Erasmus Medical Centre, Rm NH 224, PO Box 2040, 3000 CA Rotterdam, The Netherlands (e-mail: m.roobol{at}erasmusmc.nl).
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 confirm the correctness of the screening interval of 4 years. The first data that were published with respect to this choice were reassuring (4,5). Our comparative and longer term observations are confirmatory and will be helpful in developing future screening strategies.
Second, we acknowledge that the comparison was not made in a randomized setting. However, statements in the editorial addressing age and follow-up time are not correct. To achieve a similar age distribution, only men who were 55–65 years of age at the time of first screening were included. Follow-up data in both centers were complete through December 31, 2005, with a comparable mean follow-up time of 7.16 years in Rotterdam and 7.38 years in Gothenburg.
Third, contrary to the editorial, the paper does address the issue relating the screening interval to the initial prostate-specific antigen (PSA) level. Several studies on this subject are referred to in the paper. Moreover, it is mentioned in the discussion that only five of the men with interval cancers that were detected in both centers (N = 88) had a PSA level of 1.0 ng/mL or less at their first screening. In addition to the analysis of the number and characteristics of the interval cancers, the appropriateness of the length of the screening interval was also related to the tumor characteristics of the cancers detected at repeat screenings. In both centers, the rate of non–organ-confined and/or metastatic cancers was extremely low. These data provide another strong indication that the length of either a 2-year or a 4-year interval is not too long.
Finally, the suggestion to biopsy every man at the age of 50 years is, at the least, unwise. First, a prostate biopsy is not a 100% sensitive test and, without doubt, prostate cancer will be missed. But second, and most important, the amount of overdiagnosis that would occur using such a policy would be unacceptable. In this context, we would like to refer to the positive predictive value of the end-of-study biopsies in the Prostate Cancer Prevention Trial of 24.4% (6). Thus, biopsying every man regardless of PSA level would, without doubt, lead to the detection of at least half of the prostate cancers found at autopsy (the prevalence of detection at autopsy is 40%–50%). Is this really what we want to achieve?
REFERENCES
1. Crawford ED. Is a screening interval of every 4 years for prostate cancer acceptable? J Natl Cancer Inst (2007) 99(17):1280–1281.
2. Roobol MJ, Grenabo A, Schröder FH, Hugosson J. Interval cancers in prostate cancer screening: comparing a 2- and 4-year screening intervals in the European Randomized Study of Screening for Prostate Cancer, Gothenburg and Rotterdam. In: J Natl Cancer Inst (2007) 99(17):1296–1303.
3. The European Randomized Study of Screening for Prostate Cancer (ERSPC): rationale, structure and preliminary results 1994–2003. BJU Int—Roobol MJ, Schröder FH. guest, eds. (2003) 92(suppl_2):1–123.[Web of Science][Medline]
4. van der Cruisen-Koeter IW, van der Kwast ThH, Schröder FH. Interval carcinomas in the European Randomized Study of Screening for Prostate Cancer (ERSPC)—Rotterdam. J Natl Cancer Inst (2003) 95(19):1462–1466.
5. Postma R, Schröder FH, van Leenders GJLH, et al. Cancer detection and cancer characteristics in the European Randomized Study of Screening for Prostate Cancer (ERSPC)—section Rotterdam. A comparison of two rounds of screening. Eur Urol (2007) 52(1):89–97.[CrossRef][Web of Science][Medline]
6. Thompson IM, Goodman PJ, Tangen CM, et al. The influence of finasteride on the development of prostate cancer. N Engl J Med (2003) 349(3):215–224.
Related Article in JNCI
Response to this Correspondence
CiteULike 
Connotea 
Del.icio.us What's this?
J Natl Cancer Inst 2007 99: 1279-1280.
J Natl Cancer Inst 2008 100: 222-223.
J Natl Cancer Inst 2008 100: 223-224.
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||