This Tuesday researchers reported that the accuracy of a diagnostic in reading a mammogram depends on the radiologists’ ability to detect cancer. The study appears in this week’s Journal of the National Cancer Institute. They found out that per average 2 of 10 cases of breast cancer are missed when reading X-rays mammographies. They also found wide variations among radiologists’ ability to detect cancer when reading mammograms. In some of the cases there were missed 7 in 10 cancer diagnoses, meaning that detecting cancer through this test is strongly dependent on who is reading it.
As a mammography per year is recommended, after receiving a negative result, women think they’re safe for at least one year. In this regard, Dr. Leonard Berlin, chief of radiology at Rush North Shore Medical Center in north suburban Skokie, who was not involved in the study, said that "you can have cancer and still have a normal mammogram. If you have any sign or symptom, you need to pursue it. That's the bottom line."
There was a common knowledge among doctors that two radiologists looking at the same X-ray image they will often come up with different results. Also, previous studies were conducted with screening mammograms and routine tests performed on women who were assumed to be healthy.
Researchers examined the performance of 123 radiologists who interpreted 36,000 diagnostic mammograms between 1996 and 2003 at 72 U.S. health facilities. The mammograms were ordered by women who found themselves a lump in their breast or whose doctors discovered something of concern. The accuracy of detecting cancer ranged from 27 percent to 100 percent and the false-positive rate ranged from zero to 16 percent. The most accurate radiologists were ones from academic medical centers.