Many Men May Not Need Yearly Prostate Testing

Men who show no suspicious signs of prostate cancer on rectal examinationsand who also have a prostate specific antigen (PSA) level below 2.0 apparentlycould safely wait two years before their next PSA test, according to anarticle in a recent cancer theme issue of The Journal of the AmericanMedical Association (JAMA).

H. Ballentine Carter, MD, from The Johns Hopkins University School ofMedicine, Baltimore, and colleagues examined PSA measurements of 312 menwho took part in the Baltimore Longitudinal Study of Aging. Forty of thosemen eventually developed prostate cancer; the other 272 men did not haveprostate cancer. Frozen sera from the men enrolled in the study were measuredat two- and four-year intervals.

The researchers compared these measurements with case studies of 389men who were treated surgically for non-palpable prostate cancer.

In an interview, Dr. Carter said: "We were able to establish, numberone, what is the appropriate PSA level that would increase the detectionof both curable and significant cancers-and the answer to that part ofthe study was a PSA between 4.0 and 5.0.

"It turned out that prostate cancers detected at PSA levels lessthan 4.0 are almost always curable cancers-but over half of them are cancersthat are so small that treatment may not be necessary." The alternative,he says, is "watchful waiting or expectant management."

Dr. Carter says when the pre-treatment PSA level was greater than 5.0,the vast majority of tumors were significant (87%)-and 30% of them wereno longer curable.

"Large Health Care Cost Savings"

Dr. Carter says the study also found that when PSA levels are less than2.0-"rarely will the PSA level exceed 4.0 or 5.0" after two years.In other words, a two-year testing interval is apparently sufficient tosafely detect curable prostate cancer in men whose PSA levels measure lessthan 2.0.

Since 70% of a screened population of men aged 50 to 70 have PSA levelsbelow 2.0, Dr. Carter and his colleagues write: "Elimination of annualPSA testing for these men would result in large health care cost savings."

Dr. Carter emphasizes that any recommendation for PSA testing everyother year would apply only to men with PSA levels under 2.0 and no suspicionof prostate cancer found on rectal examinations. For men whose PSA levelsare above 2.0, "it would appear that yearly testing is probably necessary."