Background: Women with a history of ductal carcinoma in situ (DCIS) are at increased risk for developing a second breast cancer (SBC). A prior meta-analysis of randomized studies of radiotherapy (RT) for DCIS has shown a trend toward increased breast cancer–specific mortality after SBC, but it did not have the power needed to detect a significant difference, due to a limited number of recurrences. This study sought to evaluate the impact of RT for DCIS on mortality after SBC in a larger cohort. Patients and Methods: Using the SEER database, 3,407 patients were identified who received breast-conserving therapy with or without RT for primary DCIS in 2000 through 2013 and subsequently developed a stage I–III invasive SBC within the same time period. Fine-Gray competing risk models were used to study the association between receipt of RT and mortality after SBC. Results: Prior RT was found to be associated with higher rates of breast cancer–specific mortality (hazard ratio [HR], 1.70; 95% CI, 1.18–2.45; P=.005), even after controlling for cancer stage. Interaction analysis suggested that this risk trended higher in patients with ipsilateral versus contralateral SBC (HR, 2.07 vs 1.26; P=.16). Furthermore, compared with patients who developed contralateral SBC, those with ipsilateral SBC were younger (P<.001) and more often lacked estrogen receptor expression (P<.001). Conclusions: Patients who previously received RT for DCIS had higher mortality after developing an invasive SBC than those who did not receive RT. This finding may have implications for initial treatment decisions in the management of DCIS.
Puyao C. Li, Zilu Zhang, Angel M. Cronin, and Rinaa S. Punglia
Aileen B. Chen, Jiangong Niu, Angel M. Cronin, Ya-Chen Tina Shih, Sharon Giordano, and Deborah Schrag
Background: Understanding the sources of variation in the use of high-cost technologies is important for developing effective strategies to control costs of care. Palliative radiation therapy (RT) is a discretionary treatment and its use may vary based on patient and clinician factors. Methods: Using data from the SEER-Medicare linked database, we identified patients diagnosed with metastatic lung, prostate, breast, and colorectal cancers in 2010 through 2015 who received RT, and the radiation oncologists who treated them. The costs of radiation services for each patient over a 90-day episode were calculated, and radiation oncologists were assigned to cost quintiles. The use of advanced technologies (eg, intensity-modulated radiation, stereotactic RT) and the number of RT treatments (eg, any site, bone only) were identified. Multivariable random-effects models were constructed to estimate the proportion of variation in the use of advanced technologies and extended fractionation (>10 fractions) that could be explained by patient fixed effects versus physician random effects. Results: We identified 37,361 patients with metastatic lung cancer, 3,684 with metastatic breast cancer, 5,323 with metastatic prostate cancer, and 8,726 with metastatic colorectal cancer, with 34%, 27%, 22%, and 9% receiving RT within the first year, respectively. The use of advanced technologies and extended fractionation was associated with higher costs of care. Compared with the patient case-mix, physician variation accounted for a larger proportion of the variation in the use of advanced technologies for palliative RT and the use of extended fractionation. Conclusions: Differences in radiation oncologists’ practice and choices, rather than differences in patient case-mix, accounted for a greater proportion of the variation in the use of advanced technologies and high-cost radiation services.
Michael G. Milligan, Angel M. Cronin, Yolonda Colson, Kenneth Kehl, Debra N. Yeboa, Deborah Schrag, and Aileen B. Chen
Background: Among patients diagnosed with stage IA non–small cell lung cancer (NSCLC), the incidence of occult brain metastasis is low, and several professional societies recommend against brain imaging for staging purposes. The goal of this study was to characterize the use of brain imaging among Medicare patients diagnosed with stage IA NSCLC. Methods: Using data from linked SEER-Medicare claims, we identified patients diagnosed with AJCC 8th edition stage IA NSCLC in 2004 through 2013. Patients were classified as having received brain imaging if they underwent head CT or brain MRI from 1 month before to 3 months after diagnosis. We identified factors associated with receipt of brain imaging using multivariable logistic regression. Results: Among 13,809 patients with stage IA NSCLC, 3,417 (25%) underwent brain imaging at time of diagnosis. The rate of brain imaging increased over time, from 23.5% in 2004 to 28.7% in 2013 (P=.0006). There was significant variation in the use of brain imaging across hospital service areas, with rates ranging from 0% to 64.0%. Factors associated with a greater likelihood of brain imaging included older age (odds ratios [ORs] of 1.16 for 70–74 years, 1.13 for 75–79 years, 1.31 for 80–84 years, and 1.46 for ≥85 years compared with 65–69 years; all P<.05), female sex (OR, 1.09; P<.05), black race (OR 1.23; P<.05), larger tumor size (ORs of 1.23 for 11–20 mm and 1.28 for 21–30 mm tumors vs 1–10 mm tumors; all P<.05), and higher modified Charlson-Deyo comorbidity score (OR, 1.28 for score >1 vs score of 0; P<.05). Conclusions: Roughly 1 in 4 patients with stage IA NSCLC received brain imaging at the time of diagnosis despite national recommendations against the practice. Although several patient factors are associated with receipt of brain imaging, there is significant geographic variation across the United States. Closer adherence to clinical guidelines is likely to result in more cost-effective care.