Prostate cancer test interpretation flawed
A computer programming error caused West Penn Allegheny Health System's laboratory to send physicians incorrect interpretations of prostate cancer tests for 288 patients over 15 months.
Hospital officials say physicians who ordered the tests were advised about the errors in recent weeks. They were sent revised, corrected interpretations, said Dr. Jan F. Silverman, chairman of the Department of Pathology and Laboratory Medicine.
Silverman said actual test results were correct, and most physicians would rely on those and not interpretations. He said hospital officials found no evidence that incorrect test interpretations resulted in delayed or improper care.
The health system was following up with phone calls to physicians, who include primary care doctors and urologists, he said.
The erroneous interpretations were provided on a test physicians use to assess whether patients need biopsies of their prostates. The test provides a comparison of total prostate specific antigen, or PSA, versus free or non-attached PSA.
Dr. Ralph Miller, head of the Allegheny Prostate Cancer Center, said it was "theoretically possible, but very, very unlikely" that erroneous interpretations resulted in delayed or improper care.
Silverman said those interpretations were sent between Oct. 1, 2008 and January. Of 818 PSA tests the West Penn Allegheny Core Laboratory performed during that period, 412 included comparisons of the two PSA figures. Of those, 288 included incorrect interpretations of that ratio, Silverman said.
Miller said he does not use the comparison in his practice, although some urologists and primary care physicians do. He said some doctors find it useful for determining whether a higher than normal PSA reading warrants a biopsy to test for prostate cancer.
The comparison is one of several tests available to determine whether to perform a biopsy, Miller said. The PSA blood test and a digital exam are primary baseline tests to detect prostate cancer, he said.
The programming error was discovered recently when a physician questioned an interpretation, Silverman said.