Cancer Misdiagnoses Through Contamination Or Sample Switching

A biopsy is an unpleasant and frightening experience for most people. A recent study has brought to light one fear that many people probably do not associate with having a biopsy: the possibility of a laboratory error. In a surprising number of cases, two samples would be switched and each patient would receive the lab results of the other patient. Another common type of error analyzed in the report was the contamination of a patient’s tissue with the tissue of one or more different patients. A review of more than 13,000 samples was published in the online American Journal of Clinical Pathology recently.

The results were reported by 54 total laboratories nationwide. None of the facilities involved in the study had a perfect performance record. Some labs averaged an error rate over 3.5 percent, though the average of all the labs showed an error rate of less than 1 percent. All of the biopsies in the study were prostate specimens that were gathered in routine clinical practices.

While being told you have cancer only to later find out that you do not is traumatic, a patient with cancer who is given a clean slate may miss vital weeks or months of treatment. Cancer that can be successfully treated is given a chance to grow into a fatal condition. The authors of the study suggested that prospective DNA testing could be used to ensure that the prostate biopsies are identified with the proper patients. Clearly more needs to be done to prevent treatment errors caused by laboratory errors.

Source: Medpage Today, “Study Shows ID Errors in Prostate Biopsies,” by Charles Bankhead, 10 January 2013