Rate of inappropriate cancer scans for low-risk prostate cancer patients reduces in Sweden

Jul 25 2013

The rate of inappropriate cancer scans for low-risk prostate cancer patients in Sweden plummeted in the decade following a joint campaign to curtail such tests by Swedish County Councils and the National Prostate Cancer Register (NPCR) of Sweden, a professional association of Swedish urologists. The results, published today online in the Journal of the National Cancer Institute, suggest that curtailing unneeded medical tests, an urgent healthcare policy goal in the United States highlighted in the Choosing Wisely Campaign, among other initiatives, is achievable, says Danil V. Makarov, MD, assistant professor of urology and population health at NYU Langone Medical Center and lead author of the study.

According to Dr. Makarov, extensive cancer scans checking for metastases are discouraged for patients who have low-grade, slow-growing prostate tumors, which have almost no risk of metastasis. Though quality measures and clinical guidelines by policy organizations and professional societies to limit the use of such scans have been around for almost two decades, for various reasons many physicians have been slow to adopt them.

"In the United States we have guidelines about the overuse of imaging tests, but lack a roadmap for their implementation," says Dr. Makarov. "We could learn a lot from what the Swedes have done."

Stacy Loeb, MD, assistant professor of urology and population health and a co-author of the study says, "Imaging is very important for men with high risk prostate cancer to find out whether it has spread and guide how they are treated. However, due to prostate cancer screening, most prostate cancer is now diagnosed at an early stage. Low-risk prostate cancer is very unlikely to have spread, so imaging is not necessary, causing undue burden for the patients and costs for the healthcare system."

In the study, Drs. Makarov and Loeb at NYU Langone collaborated with Swedish colleagues at Umeå University, Regional Cancer Center Uppsala University Hospital and Karolinska Institute, as well as at New York's Memorial Sloan-Kettering Cancer Center to examine the records of approximately 100,000 Swedish men diagnosed with prostate cancer from 1998 until 2009. In 2000, the NPCR began a campaign to reduce inappropriate diagnostic imaging among men with low-risk prostate cancer. The campaign involved openly and publicly presenting local statistics on inappropriate imaging at urology meetings, along with reminders about imaging guidelines. Urologists in Sweden could then see imaging rates at their own institution compared to best practices and had an incentive not to be listed as a provider of unnecessary testing. "I think you could consider the tactic a way of "gentle shaming" of the health care providers who did not follow the guidelines" says Dr. Makarov.

The result: During the study period, the percentage of scans deemed inappropriate plummeted from 45% to 3% among patients with low-risk prostate cancer.

"It's recognized that the chance of finding metastases in these patients is very small, and the downsides of the scans include unnecessary costs, a lengthy diagnostic procedure including injection of a radioactive isotope, treatment delays, and, of course, unnecessary worries about advanced disease before the test results are available or after a falsely positive examination," said Dr. Makarov.

However, Dr. Makarov and his colleagues noted that the campaign brought an unwanted side effect: the rate of appropriate scans in patients with high-risk tumors also fell, to 47% from 63%.

"The caveat here is that when guidelines are implemented to limit the inappropriate use of a healthcare resource, the appropriate use of that resource should be simultaneously encouraged—otherwise those patients who most need the resource may no longer have access to it," said Dr. Makarov. "But the true lesson from this study is that inappropriate utilization of healthcare resources can be reduced by giving feedback to practitioners."

In research published last year, Dr. Makarov found that the use of inappropriate prostate cancer imaging in the United States tends to vary greatly from one part of the country to the next—from 62% among New Jersey patients to just 22% for those in Utah. "Whether or not you are imaged in the United States seems to depend as much on where you live as on the characteristics of your disease," he said.

Instituting a Swedish-style awareness-raising campaign at urological conferences could result in more uniform and appropriate imaging rates in the United States, suggests Dr. Makarov. He also notes that The NPCR collaborates with county-level authorities to set the policy agenda and implement best practices. "Encouraging medical professional societies in the United States to collaborate with the government is another possible strategy to explore," he suggests.