Understanding Racial and Ethnic Inequities in Uptake and Outcomes Following Multigene Prognostic Testing in Early Breast Cancer: The Promise of Real-World Data.

In the past decades, multigene prognostic testing, such as Oncotype DX (ODX), has been increasingly used to inform treatment decisions for patients with early-stage breast cancer. This advance in precision oncology has increased existing concerns about differential access to genomic testing across racial and ethnic groups. The investigation by Moore and colleagues, analyzing real-world data from the National Cancer Database, shows that patients of color with breast cancer were less likely to receive ODX testing and Black patients were more likely to have a high risk Recurrence Score (RS) compared with White patients. This study emphasizes that the appropriate adoption of ODX testing is critical to promote equitable cancer care for patients with breast cancer. The reported associations on overall survival across specific racial and ethnic groups provided here give additional insight to the known associations between the ODX RS and outcomes of distant recurrence and cancer-specific mortality. Analyses of contemporary, real-world data from diverse populations with long-term follow-up should continue to keep pace with the expansion of precision breast cancer care to better understand and mitigate potentially widening inequities in genomic testing. See related article by Moore et al., p. 821.

Limitations of body surface area-based activity calculation for radioembolization of hepatic metastases in colorectal cancer.

PURPOSE: To calculate absorbed radiation doses in patients treated with resin microspheres prescribed by the body surface area (BSA) method and to analyze dose-response and toxicity relationships. MATERIALS AND METHODS: A retrospective review was performed of 45 patients with colorectal carcinoma metastases who received single-session whole-liver resin microsphere radioembolization. Prescribed treatment activity was calculated using the BSA method. Liver volumes and whole-liver absorbed doses (D(WL)) were calculated. D(WL) was correlated with toxicity and radiographic and biochemical response. RESULTS: The standard BSA-based administered activity (range, 0.85-2.58 GBq) did not correlate with D(WL) (mean, 50.4 Gy; range, 29.8-74.7 Gy; r = -0.037; P = .809) because liver weight was highly variable (mean, 1.89 kg; range, 0.94-3.42 kg) and strongly correlated with D(WL) (r = -0.724; P < .001) but was not accounted for in the BSA method. Patients with larger livers were relatively underdosed, and patients with smaller livers were relatively overdosed. Patients who received D(WL) > 50 Gy experienced more toxicity and adverse events (> grade 2 liver toxicity, 46% vs 17%; P < .05) but also responded better to the treatment than patients who received D(WL)< 50 Gy (disease control, 88% vs 24%; P < .01). CONCLUSIONS: Using the standard BSA formula, the administered activity did not correlate with D(WL). Based on this short-term follow-up after salvage therapy in patients with late stage metastatic colorectal carcinoma, dose-response and dose-toxicity relationships support using a protocol based on liver volume rather than BSA to prescribe the administered activity.