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Unavailable Prior Comparison Mammograms:  A Huge Problem in Private Practice (not-so-much for Academicians)

Posted by Kathryn Pearson Peyton, MD | 04.25.2016

Kathryn Pearson Peyton, MD, is the founder, CEO and Chief Medical Officer for Mammosphere, now part of lifeIMAGE. Dr. Pearson leads the women’s health and imaging advisory committee at lifeIMAGE.

Approximately 1 in every 4 patients presents for a mammography exam without her prior mammogram available for comparison 1-4. This rate is even higher in the indigent population 5-7 with estimates of 30-40%. Despite diligent and costly efforts to retrieve those prior exams from outside imaging centers, 50% of those patient priors are not received within two weeks 4, so the current mammogram is interpreted without assessing for interval changes, or stability, compared to prior images. Numerous radiology research reports demonstrate that mammography interpretation with the prior comparison exam is clearly more accurate: decreased false-positive recalls by 40-60% and improved earlier breast cancer detection by 25% 3,8-16

The false-positive recall rate for screening mammograms varies tremendously on availability of prior comparison exams. This average recall rate for mammography screening in the United States is approximately 10% (9.7%, range 6-13%)17, whereas in some European countries that provide access to all prior mammograms through a national network, the recall rate is consistently between 1-3% 18,19 (in part also influenced by differences in medico-legal risk).

As we delve into this medical audit data further, we are recognizing that the same radiologists have extremely different performance measurements depending on WHERE they are reading exams. For example, at the Institute of Medicine (IOM) Workshop of 2015 on “Assessing & Improving the Interpretation of Breast Images” (NCBI) 20, Jennifer Harvey, MD, Chief of Breast Imaging at the University of Virginia School of Medicine in Charlottesville, reported that her same radiologists had extremely discrepant performance audit data between different breast centers – same medico-legal environment, similar geography, but different populations ranging from inner-city Baltimore to wealthy suburban to rural site on eastern shore. For example, at the site in the city serving an under-resourced population, the recall rate is 16 percent and the cancer detection rate is 8 per 1,000 women. But when the same group of radiologists read in the suburban site, the recall rate is 9 percent and the cancer detection rate is 3 per 1,000 women.

If Dr. Harvey’s statistical differences were just due to different patient populations with different cancer rates, then the cancer detection rates would be different while recall rates would be similar. Likely, the differences in recall rate performance are due to differences in screening consistency and resultant breast center availability of prior exams: more readily available comparisons with repeat patient customers, versus lack of available prior exams with under-resourced or more migratory patients. Analysis of the population differences are apparent in the cancer detection rates (8/1000 versus 3/1000), which reflect the standard reported differences in women who are not regularly screened (10/1000) versus women who are regularly screened (2/1000) 16,21.

Academicians in breast imaging are less affected by the widespread problem of access to prior mammograms – high percentage of repeat patient customers that seek Centers of Excellence, motivated patients with need for consultations or breast cancer treatment, and stronger minion force in procuring prior studies. Many academic centers do care for the indigent or under-resourced population who are less likely to recall place of prior imaging 5-7 - seeking free mammography care wherever it is offered -, and those centers demonstrate much higher recall rates (false-positives) for the same radiologists 22.

Radiologists reading mammograms outside of large academic centers are more susceptible to migratory patients who present without available prior mammograms. These radiologists are generally under more pressure to reduce report turnaround times to propagate their private practice value. The majority of mammograms in the United States are interpreted by general radiologists, who interpret mammograms as a small percentage of their overall caseload and hence depend even more on prior mammograms for confident interpretations 23. Anecdotal stories are rampant with radiologists complaining of lack of prior studies being “the biggest pain-point of their day,” increasingly pressured to interpret the exam – with difficulty and frustration – without available comparison studies. In Jonathan Bush’s book, Where Does It Hurt?: An Entrepreneur's Guide to Fixing Health Care 24, he notes that hospitals are even “holding hostage” the prior exams and medical records, making it exceedingly difficult to produce and send out prior comparison studies, hoping this will dissuade patients from seeking care elsewhere. These hospitals feel that even unhappy patients will stay put within their system due to the difficulties in transferring their own records.

So this is when the insurance payer gets involved. After all, the lack of available prior exams hits the payer with the biggest pain point: higher false-positive recalls mean more unnecessary imaging and biopsies; comparison exams allow for earlier detected cancers that require less costly treatments. Brian Loy, MD, MBA (Humana, Vice President, Oncology, Laboratory and Personalized Medicine) noted in the IOM Workshop of 2015 that we need to reduce barriers that impede access to prior exams 20. Perhaps the insurance companies will incentivize obtaining prior mammograms for the more accurate interpretation – a case for value-based incentive payments? Mammosphere is improving access to prior comparison mammograms by providing a technical solution for secure, electronic access and exchange of prior comparison exams. This will significantly improve radiologists’ mammography image interpretation, thereby improving patient care while reducing societal costs.

Soon the day will come when patients are empowered, or incentivized, to own and manage their own imaging studies, much as they already do with family photo albums in the cloud. As physicians and medical records staff are increasingly overworked in the EMR/PHR world, women need to take control of the future of their own health by demanding or supplying their own prior comparison studies electronically with the push of a button.



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