Patients with early-stage breast cancer still undergo imaging for distant metastases despite evidence-based local, national, and international guidelines—and a recommendation from ASCO—to avoid such imaging, according to a retrospective review of staging imaging for distant metastases in patients with primary early-stage breast cancer treated at a large Canadian academic cancer center.
Demetrios Simos, MD, of Ottawa Hospital Cancer Center, and colleagues reviewed 200 patient medical records, 100 from patients treated before and 100 from patients treated after publication of ASCO’s Top Five Recommendations for Choosing Wisely in Oncology in 2012. One of the recommendations was to avoid routine use of staging imaging in patients with early-stage breast cancer and no clinical findings to suggest metastatic disease.
“ASCO recommended against the routine use of staging imaging in asymptomatic patients with early-stage disease, arguing that this practice has never been shown to extend survival, is costly, and in some cases may lead to harm, because false-positive results from such tests may necessitate invasive procedures and overtreatment, all of which can impair quality of life,” the authors wrote in the Journal of Oncology Practice. They also noted that the ASCO recommendation “is in keeping with the spirit of the published guidelines.”
The mean age of patients was 60 years; 57% of tumors were self-detected; 89% were pathologic stage I or II disease, and 11% were stage III. Overall, 169 patients (84.5%) had at least one imaging test (mean, 3.6 tests per imaged patient). Of the 608 total imaging tests, 500 (82.2%) “were initial imaging tests assessing the most common metastatic sites for breast cancer (ie, skeleton, thorax, and abdomen), whereas the remaining 108 tests (17.8%) were confirmatory imaging tests,” the investigators stated.
Confirmatory imaging to clarify indeterminate initial imaging was performed in 51 (30.2%) of the 169 women undergoing imaging. None of the patients with stage I or II disease had metastatic disease detected by imaging. Metastatic disease was ultimately detected by imaging in two women, both with pathologic N3 (stage IIIC) disease detected by postoperative computed tomography (one with lung metastases and the other with liver metastases).
“Overall, 77% (154 of 200) and 75% (150 of 200) of the patients reviewed in our study underwent imaging for distant metastases, [which was] not in keeping with the spirit of the provincial guidelines and ASCO recommendations, respectively,” the researchers reported. The frequency of imaging did not change after the ASCO recommendations were published.
“Generally, the majority of patients with stage I or II disease underwent excessive imaging relative to these recommendations, and almost all patients with stage III disease underwent imaging of the skeleton, abdomen, and thorax, as recommended,” the investigators observed. Factors associated with undergoing more staging imaging than recommended included ductal histology, lower-stage disease, and a community vs academic hospital.
The lack of demonstrated benefit and the potential for harm from imaging for metastatic disease in asymptomatic patients mean that such imaging “should be avoided,” the authors concluded. “If guideline recommendations are to be implemented in practice, clearly additional knowledge translation strategies are needed beyond the simple publication of guideline documents.” ■
Simos D, et al: J Oncol Pract. November 12, 2014 (early release online).