Predictors of receiving targeted treatment among eligible patients with metastatic colorectal cancer.

Abstract

e15594 Background: Colorectal cancer is among the most frequently diagnosed cancers and ranks as the third leading cause of cancer-related mortality globally with increasing prevalence among younger patients and high mortality. While targeted therapies have revolutionized treatment and tripled the median survival over the past two decades, many eligible patients fail to receive them. This study sought to identify factors associated with receiving targeted treatment among eligible patients. Methods: We identified a cohort of patients with metastatic colorectal cancer diagnosed between 2007 and 2023 (n = 521,074) in Optum’s clinicogenomic database. Eligible patients were identified based on clinical and treatment history, broad-panel next-gen sequencing (NGS) results and the drug indications for targeted treatments available at time of diagnosis (n = 8,533), including MSI/MMR status, RAS WT status, presence of BRAF V600E, and other biomarkers. In total, we considered tucatinib, encorafenib, pembrolizumab, nivolumab, ipilimumab, panitumumab, cetuximab, and regorafenib. Most patients did not receive targeted treatment; we applied a synthetic minority oversampling technique to correct this class imbalance. We assessed how factors including sex, race, and receipt of genetic counseling services influenced the likelihood of receiving targeted treatment using logistic regression. Results: In the fully adjusted multivariable logistic regression analysis, all variables were significant with p < 0.05. Notably, patients receiving genetic counseling had 68% greater odds of receiving targeted treatment (OR, 1.68 [95% CI, 1.20-2.36]). African American (OR, 0.37 [95% CI, 0.27-0.50]) and Asian patients (OR, 0.10 [95% CI, 0.04-0.24]) had lower odds of receiving targeted treatment compared to Whites. Similarly, patients treated in community settings had 86% lower odds compared to patients in academic settings (OR, 0.14, [95% CI, 0.11-0.18]) as did male patients (OR, 0.39, [95% CI, 0.33-0.44]). Conclusions: This study underscores the challenges in receiving targeted treatments despite clinical eligibility. Our findings highlight the significance of genetic counseling in facilitating access to targeted therapies, and the stark gap in uptake among minority patients. These results can inform strategies to increase access to these treatments. Future research will attempt to better understand the mechanisms underlying receipt of targeted treatment.