Prostate Cancer Screening (PDQ®): Screening - Health Professional Information [NCI] - Evidence of Benefit
Summary of First Four Prostate, Lung, Colorectal, and Ovarian Screening Roundsa continued...
Another study adopted a change in the PSA cutoff to a level of 3.0 ng/mL to study the impact of this change in 243 men with PSA levels between 3.0 ng/mL and 4.0 ng/mL. Thirty-two of the men (13.2%) were ultimately found to have prostate cancer. An analysis of radical prostatectomy specimens from this series found a mean tumor volume of 1.8 cc (range, 0.6–4.4). The extent of disease was significant in a number of cases, with positive margins in five cases and pathologic pT3 disease in six cases.
Frequency of screening
The optimal frequency and age range for PSA (and DRE) testing are unknown.[68,76,77] Cancer detection rates have been reported to be similar for intervals of 1 to 4 years. With serial annual screening in the PLCO trial, 8% of men with baseline PSA lower than 1 ng/mL had a prostate cancer diagnosis within 2 years. In the same trial, 2-year intervals in screening produced average delays of 5.4 to 6.5 months, while 4-year screening intervals produced average delays of 15.6 months (baseline PSA < 1 ng/mL) to 20.9 months (baseline PSA 3–4 ng/mL). While the authors caution that an optimal prostate screening frequency cannot be determined from these data, they conclude that among men who choose to be screened, these data may provide a context for determining a PSA screening schedule.
A report from the ERSPC trials demonstrated that while more frequent screenings lead to more diagnosed cancers, the detection rates for aggressive interval cancers was very similar with the different screening intervals in place in the two countries reporting (0.11 with a 4-year interval in Rotterdam and 0.12 with a 2-year interval in Gothenburg). The report suggests that mortality outcomes from the ERSPC (2- and 4-year intervals) and PLCO (1-year interval) trials should facilitate a more reliable assessment of the benefits and costs of different screening intervals.
Types of Tumors Detected by Prostate Cancer Screening