Prostate cancer screening interval of 4 years misses few cancers

Screening for prostate cancer every 4 years using prostate-specific antigen (PSA) testing, digital rectal exam (DRE), and transrectal ultrasound (TRUS) will adequately detect most cancers, suggest data from the ongoing European Randomized Study of Screening for Prostate Cancer (ERSPC-Rotterdam).

The rate of interval cancers – those detected between screening visits – is an “important parameter for determining the sensitivity of the screening procedure and the proper screening interval,” Dr. Ingrid W. van der Cruijsen-Koeter and colleagues note in the October 1st in The Journal of the National Cancer Institute.They determined the rate of interval carcinomas in a cohort of 17,226 men ages 55 to 74 enrolled in the ERSPC-Rotterdam trial. The 8350 men in the intervention arm underwent screening on two scheduled occasions 4 years apart. The 8876 men in the control arm did not receive scheduled screening. The team checked the Dutch national cancer registry annually for cases of prostate cancer among all participants.The rate of interval cancers was “exceedingly low,” the investigators from Erasmus MC, University Medical Center in Rotterdam, the Netherlands report.During the 4-year-period, 135 cancers were diagnosed in the control arm compared with just 25 in the screened arm. Seven of the 25 cancers in the screened arm occurred in men who had refused a recommended biopsy at their initial screen, leaving 18 “true” interval cancers.When considering these 18 cancers, the 4-year screening interval has a “high sensitivity” of 85.5%, the authors say.All of the interval tumors were locally confined (stages T1A-C or T2A), suggesting to the team that “very few, if any, aggressive prostate cancers escape screening with the procedures used within the ERSPC.”(Source: J Natl Cancer Inst 2003;95:1462-1466: Reuters Health: September 30, 2003: Oncolink)