Intensity modulated radiation therapy following lumpectomy in early-stage breast cancer: Patterns of use and cost consequences among Medicare beneficiaries.

PURPOSE: In 2013, the American Society for Radiation Oncology (ASTRO) issued a Choosing Wisely recommendation against the routine use of intensity modulated radiotherapy (IMRT) for whole breast irradiation. We evaluated IMRT use and subsequent impact on Medicare expenditure in the period immediately preceding this recommendation to provide a baseline measure of IMRT use and associated cost consequences. METHODS AND MATERIALS: SEER records for women ≥66 years with first primary diagnosis of Stage I/II breast cancer (2008-2011) were linked with Medicare claims (2007-2012). Eligibility criteria included lumpectomy within 6 months of diagnosis and radiotherapy within 6 months of lumpectomy. We evaluated IMRT versus conventional radiotherapy (cRT) use overall and by SEER registry (12 sites). We used generalized estimating equations logit models to explore adjusted odds ratios (OR) for associations between clinical, sociodemographic, and health services characteristics and IMRT use. Mean costs were calculated from Medicare allowable costs in the year after diagnosis. RESULTS: Among 13,037 women, mean age was 74.4, 50.5% had left-sided breast cancer, and 19.8% received IMRT. IMRT use varied from 0% to 52% across SEER registries. In multivariable analysis, left-sided breast cancer (OR 1.75), living in a big metropolitan area (OR 2.39), living in a census tract with ≤$90,000 median income (OR 1.75), neutral or favorable local coverage determination (OR 3.86, 1.72, respectively), and free-standing treatment facility (OR 3.49) were associated with receipt of IMRT (p<0.001). Mean expenditure in the year after diagnosis was $8,499 greater (p<0.001) among women receiving IMRT versus cRT. CONCLUSION: We found highly variable use of IMRT and higher expenditure in the year after diagnosis among women treated with IMRT (vs. cRT) with early-stage breast cancer and Medicare insurance. Our findings suggest a considerable opportunity to reduce treatment variation and cost of care while improving alignment between practice and clinical guidelines.

IHC4 score plus clinical treatment score predicts locoregional recurrence in early breast cancer.

PURPOSE: Immunohistochemical 4 (IHC4) score plus Clinical Treatment Score (CTS) is an inexpensive tool predicting risk of distant recurrence in women with early breast cancer (EBC). IHC4 score is based on ER, PR, HER2 and Ki67 index. This study explores the role of the combined score (IHC4 + CTS) in predicting risk of locoregional recurrence (LRR) in women with EBC who had breast conservation surgery (BCS) without adjuvant radiotherapy (study group). The secondary objective was to evaluate the clinicopathological differences between our study group and women who had adjuvant radiation following BCS (control group). METHODS AND MATERIALS: Patients were selected from the local database over a 13-year period. IHC testing was done where results were missing. Combined scores were calculated using the appropriate formulae. RESULTS: Patients in the study group (81 patients) had favorable clinicopathological features compared to the control group (1406 patients). The Cox regression indicated a statistically significant association between the combined score and the risk of LRR (p = 0.03). The incidence of LRR was zero, 20% and 33.3% in the low, intermediate and high risk groups respectively (p = 0.007). Margin status was the only variable not included in the combined score. The Cox regression analysis demonstrated that the combined score (p = 0.02) and the ordinal measure of margins (p = 0.03) were significant independent predictors of LRR. CONCLUSION: This is the first study of its kind. The IHC4 score + CTS can be used to identify low risk women who can potentially avoid adjuvant radiotherapy.