Purpose

Guidelines on mammographic surveillance after breast cancer treatment have been disseminated internationally and incorporated into Choosing Wisely recommendations to reduce low-value care. However, adherence within different countries before their publication is unknown.

Methods and Materials

Low-value mammography, defined as “short-interval” (within 6 months of radiation) or “high-frequency” (>1 within 12 months of radiation), was compared in Medicare fee-for-service in the United States and Ontario, Canada. Women ≥65 years diagnosed with breast cancer who underwent breast-conserving therapy with a minimum of 24 months of follow-up were included (n = 19,715 United States; 6479 Ontario). Secondary outcomes were patient and physician characteristics associated with discordance.

Results

Short-interval mammography was higher in the United States than in Ontario (55.9% vs 38.0%, P < .001), as was high-frequency (39.6% vs 7.9%, P < .001). In Ontario, younger age (42% ≥85 vs 58% <74 years, P < .001) and chemotherapy (69% vs 51%, P < .001) were associated with short-interval mammography; in the United States, age, earlier diagnosis year, stage, chemotherapy, rurality, and academic center treatment were associated with greater use. Chemotherapy was associated with high-frequency mammography in both countries (13% vs 7% in Ontario, P < .001; 69% vs 51% in United States, P = .02); younger age, earlier diagnosis year, stage, and nonacademic center treatment were associated in the United States. In both countries, radiation oncologists had the highest proportion of providers ordering low-value mammograms.

Conclusions

Despite significant evidence guiding surveillance mammography recommendations, there are high rates of short-interval mammography in both the United States and Ontario, and high rates of high-frequency mammography in the United States. Further international efforts, such as Choosing Wisely, are needed to reduce low-value mammography.

中文翻译：

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加拿大和美国老年乳腺癌患者的乳房 X 光检查：我们的选择是否明智？

目的

乳腺癌治疗后乳房 X 线摄影监测指南已在国际上传播，并纳入了“明智选择”的建议，以减少低价值护理。然而，在出版之前不同国家的遵守情况尚不清楚。

方法和材料

低值乳房 X 光检查，定义为“短间隔”（辐射 6 个月内）或“高频”（辐射 12 个月内 >1），在美国和安大略的 Medicare 按服务收费中进行了比较， 加拿大。包括接受保乳治疗且至少随访 24 个月的 65 岁以上诊断为乳腺癌的女性（n = 19,715 美国；6479 安大略）。次要结果是与不一致相关的患者和医生特征。

结果

美国的短间隔乳房 X 光检查率高于安大略省（55.9% 对 38.0%，P < .001），高频（39.6% 对 7.9%，P < .001）也是如此。在安大略省，较年轻的年龄（42% ≥ 85 岁 vs 58% < 74 岁，P < .001）和化疗（69% 对 51%，P < .001）与短间隔乳房 X 光检查有关；在美国，年龄、早期诊断年份、分期、化疗、农村和学术中心治疗与更多使用有关。在这两个国家，化疗与高频乳房 X 光检查相关（安大略省 13% 对 7%，P < .001；美国 69% 对 51%，P = .02); 在美国，年龄较小、诊断年份较早、分期和非学术中心治疗与此相关。在这两个国家，放射肿瘤学家订购低价值乳房 X 光检查的提供者比例最高。

结论

尽管有大量证据指导监测乳房 X 线照相术的建议，但美国和安大略省的短间隔乳房 X 光检查率很高，美国的高频乳房 X 光检查率也很高。需要进一步的国际努力，例如明智选择，以减少低价值的乳房 X 光检查。