SS 23 - Breast 3?- General
164 - Using Clinical Pathways to Standardize Adoption of Hypofractionated Whole-breast Irradiation for Women Younger Than 50
Tuesday, October 23
2:00 PM - 2:10 PM
Location: Room 303
Using Clinical Pathways to Standardize Adoption of Hypofractionated Whole-breast Irradiation for Women Younger Than 50
J. L. Rodriguez-Lopez1, D. C. Ling1, D. E. Heron2, and S. Beriwal2; 1Department of Radiation Oncology, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, 2UPMC Hillman Cancer Center, Pittsburgh, PA
Purpose/Objective(s): Current ASTRO guidelines recommend the use of hypofractionated whole-breast irradiation (HF-WBI) for women age ≥50 with breast cancer, although this age cut-off is currently being revised based on long-term follow-up of several randomized trials showing no difference in outcome between hypofractionation and conventional fractionation by age. Yet, HF-WBI remains underutilized in North America even in women age ≥50. We have previously shown that we were able to change the practice pattern for women age ≥50 using clinical pathways, which mandated hypofractionation in this population. We next sought to evaluate whether we could use clinical pathway modifications to achieve a similar effect on adoption of HF-WBI for women younger than 50 within a large, integrated radiation oncology network of 17 sites.
Materials/Methods: The breast clinical pathway was modified in January 2016 (Amendment 1) to allow HF-WBI as a pathway-concordant treatment option for women age <50, while conventional fractionation was maintained as the preferred option. In December 2016, the pathway was modified to mandate HF-WBI as the only pathway-concordant option (Amendment 2). All pathway-discordant plans were subject to peer-review and justification. Women younger than age 50 treated for stage 0-IIA breast cancer were included in this analysis. Patients were excluded if the regional lymph nodes were treated. Potential predictors of use of hypofractionation were analyzed using binary logistic regression, including timing of patient appointment in relation to pathway amendments (before, after Amendment 1, and after Amendment 2), age, and practice setting (community vs. academic).
Results: We identified 305 patients younger than age 50 treated from 2013 to 2017 who met inclusion criteria. Median age was 46 years (range: 22-50). From 2013 to December 2015, the utilization rate of HF-WBI was 4.2%. After the first and second amendments, its use significantly increased to 53.1% (p <0.001, OR 25.87, 95% CI 10.80-61.96) and 96.5% (p <0.001, OR 628.57, 95% CI 126.77-3116.61), respectively. Prior to Amendment 1, there was no difference in the use of hypofractionation at academic (2.6%) vs. community (4.7%) sites (p=0.568). After Amendment 1, academic practices were significantly more likely to use hypofractionation (72.0% vs 44.6%, p=0.026, OR 3.19, 95% CI 1.15-8.84). After Amendment 2, there was again no significant difference in the use of hypofractionation between academic (100.0%) and community (95.3%) practices (p=0.999).
Conclusion: With implementation of a clinical pathway amendment, which mandated use of HF-WBI regardless of age, the utilization of HF-WBI for women younger than 50 rapidly increased from 4.2% to >95%. Clinical pathways are a useful tool in standardizing patterns of care to reflect the most up to date clinical evidence.
Author Disclosure: J.L. Rodriguez-Lopez: None. D.C. Ling: None. D.E. Heron: No personal compensation; Accuray Exchange in Radiation Oncology. Partnership; Cancer Treatment Services International. Vice Chairman of Clinical Affairs; University of Pittsburgh School of Medicine. Director of Radiation Services; UPMC CancerCenter. S. Beriwal: None.