Background: The 21-gene recurrence score (RS) assay is retrospectively validated for assessing prognosis and benefit from chemotherapy in hormone receptor–positive, early-stage breast cancer (EBC) with low RS. We hypothesized that oncologists have already incorporated the RS assay for decision-making in higher-risk, node-positive disease, despite the lack of prospective data and contrary to NCCN Guideline recommendations. This study provides the first analysis of trends and differences in RS use and therapeutic implications in a population-based data set of patients with node-positive EBC. It also assesses the impact of the RxPONDER trial on clinicians' chemotherapy recommendations. Methods: Node-positive EBC cases diagnosed during 2010 through 2012 and included in the National Cancer Data Base were used. Multivariate logistic regression was used to estimate test use and impact on chemotherapy recommendations. Results: The RS assay was ordered for 16.5% of the 80,405 identified patients. Of all variables, the RS assay had the strongest association with chemotherapy recommendation, with adjusted odds ratios (AORs) of 19 for scores >30. Odds of chemotherapy recommendation were significantly lower for the group who received the test (AOR, 0.21; 95% CI, 0.20–0.22). When divided based on the cutoff point of 25 adopted by the RxPONDER trial, those with an RS of 18 to 25 had significantly lower odds of chemotherapy recommendation compared with those with an RS of 26 to 30 (AOR, 0.32; 95% CI, 0.26–0.40). Test use was lower for blacks, community centers, uninsured/governmentally insured patients, higher tumor grade, larger tumor size, and more nodes involved. Chemotherapy recommendation was higher for patients of younger age, with private insurance, and with higher tumor grade, size, and number of nodes involved. Black patients had significantly higher RS (AOR, 1.37; 95% CI, 1.25–1.79). Conclusions: The RS assay influences clinicians' chemotherapy recommendation in node-positive EBC. Clinicians are using the inclusion criteria of the RxPONDER trial before its final release. Black patients have higher RS, likely representing worse biology. Significant differences exist in test use and clinical implications based on race, insurance, and facility.
Jagar Jasem, Christine M. Fisher, Arya Amini, Elena Shagisultanova, Rachel Rabinovitch, Virginia F. Borges, Anthony Elias and Peter Kabos
Richard Li, Wei-Hsien Hou, Joseph Chao, Yanghee Woo, Scott Glaser, Arya Amini, Rebecca A. Nelson and Yi-Jen Chen
Background: Limited data are available to guide management of patients with stage I–III gastric cancer not undergoing potentially curative surgical resection. We compared survival outcomes associated with chemotherapy alone versus chemoradiation (CRT) in the treatment of nonmetastatic gastric cancer. Methods: Patients with gastric adenocarcinoma from 2004 to 2015 were identified using the National Cancer Database. Patients were excluded if they had surgery, metastatic disease, or T0, Tis, or T1a disease. Logistic regression was used to evaluate predictors of CRT use. Cox proportional hazards modeling was performed to compare overall survival (OS) between chemotherapy alone and CRT in overall and propensity score–matched cohorts. Results: We identified 4,795 patients with stage I–III gastric adenocarcinoma who did not undergo surgery, at a median follow-up of 11.8 months. A total of 3,316 patients (69.2%) received chemotherapy alone and 1,479 patients (30.8%) received CRT. Predictors of increased CRT use were age ≥65 years (odds ratio [OR] 1.68; 95% CI, 1.43–1.99; P<.001), Charlson-Deyo comorbidity score ≥2 (OR, 1.46; 95% CI, 1.18–1.81), and treatment at a community facility (OR, 1.27; 95% CI, 1.07–1.51; P=.006). Patients receiving CRT had a 2-year OS rate of 28.3% compared with 21.5% among those receiving chemotherapy. Multivariate analysis showed that CRT was associated with improved OS (hazard ratio [HR], 0.82; 95% CI, 0.77–0.89; P<.001). After propensity score matching, a persistent survival benefit was observed (HR, 0.80; 95% CI, 0.74–0.88; P<.001). Conclusions: In patients with stage I–III gastric cancer not undergoing surgical resection, CRT was associated with improved survival compared with chemotherapy alone. However, only 30.8% of patients received CRT in this setting.