Search

The Cancer and Leukemia Group-B 9343 (CALGB 9343) trial demonstrated that women aged ≥ 70 years with early-stage breast cancer can safely omit radiation therapy (RT) and be treated with breast-conserving surgery (BCS) and adjuvant endocrine therapy (AET) alone. AET adherence is low, leaving an undertreated cohort who may be at increased risk of recurrence and death. We hypothesized that AET adherence and adjuvant treatment choice impact recurrence and survival among CALGB 9343 eligible women. SEER-Medicare was used to identify CALGB 9343 eligible women who underwent BCS between 2007 and 2016. Medicare claims were used to identify AET use, and the proportion of days covered by AET was used to categorize adherent (PDC ≥ 0.80) versus nonadherent patients (PDC

Using long-term survival data from the C9343 trial as a temporal reference point, this study aimed to determine radiation therapy (RT) treatment trends for older patients with early-stage breast cancer. The study also examined rates of adherence to adjuvant endocrine therapy (AET). The surveillance, epidemiology, and end results–medicare database was used to identify women with a diagnosis of breast cancer from 2007 through 2016. Bivariate associations were calculated to determine variable characteristics by time frame (group 1: 2007–2012 vs. group 2: 2013–2016). Multivariate logistic regression was used to estimate the effect of group on the RT use and AET adherence. The temporal rates for both RT and AET adherence over time were plotted. The final study cohort included 12,210 Medicare beneficiaries. Use of RT differed significantly between the groups, with a higher proportion omitting RT in the later period (25% of group 2 vs. 20% of group 1; p

The Cancer and Leukemia Group-B 9343 (CALGB 9343) trial demonstrated that women aged ≥ 70 years with early-stage breast cancer can safely omit radiation therapy (RT) and be treated with breast-conserving surgery (BCS) and adjuvant endocrine therapy (AET) alone. AET adherence is low, leaving an undertreated cohort who may be at increased risk of recurrence and death. We hypothesized that AET adherence and adjuvant treatment choice impact recurrence and survival among CALGB 9343 eligible women.SEER-Medicare was used to identify CALGB 9343 eligible women who underwent BCS between 2007 and 2016. Medicare claims were used to identify AET use, and the proportion of days covered by AET was used to categorize adherent (PDC ≥ 0.80) versus nonadherent patients (PDC 0.80). Recurrence-free, cancer-specific, and overall survival were assessed using Cox proportional hazards models.In total, 10,719 women were identified, of whom 780 (7.3%) underwent BCS alone, 1490 (13.9%) underwent BCS + RT, 1663 (15.5%) underwent BCS + AET, and 6786 (63.3%) had BCS + RT + AET. Among women treated with BCS + AET, adherent patients had lower recurrence than did nonadherent patients (HR = 0.65, 95% CI: 0.50-0.85). With respect to adjuvant treatment combinations, there was no recurrence difference between the BCS + RT + AET group and BCS + AET group (HR = 0.81, 95% CI: 0.54-1.21). There was equivalent cancer-specific but worse overall survival in the BCS + AET group versus the BCS + AET + RT group.While BCS + RT + AET may represent overtreatment for some, AET nonadherent women who omit RT are at risk for worse outcomes. Treatment decisions regarding RT omission should be tailored to the individual patient, taking into consideration the chances of AET nonadherence and the patients' own risk tolerance.

Using long-term survival data from the C9343 trial as a temporal reference point, this study aimed to determine radiation therapy (RT) treatment trends for older patients with early-stage breast cancer. The study also examined rates of adherence to adjuvant endocrine therapy (AET).The surveillance, epidemiology, and end results-medicare database was used to identify women with a diagnosis of breast cancer from 2007 through 2016. Bivariate associations were calculated to determine variable characteristics by time frame (group 1: 2007-2012 vs. group 2: 2013-2016). Multivariate logistic regression was used to estimate the effect of group on the RT use and AET adherence. The temporal rates for both RT and AET adherence over time were plotted.The final study cohort included 12,210 Medicare beneficiaries. Use of RT differed significantly between the groups, with a higher proportion omitting RT in the later period (25% of group 2 vs. 20% of group 1; p 0.001). In both groups, after adjustment for covariates, the patients with RT omitted were statistically less likely to adhere to AET [group 1: odds ratio (OR), 0.74; p 0.001 vs. group 2: OR, 0.66; p 0.001].This study, 15 years after publication of the of the C9343 trial results, showed minimal change in practice, with most older women receiving RT. Importantly, AET adherence was significantly lower in the non-RT group. For women who meet the criteria to have adjuvant RT omitted, nonadherence to AET could result in undertreatment of their breast cancer, and RT should not be considered overtreatment.