Abstract 2237: Determinants of time to cancer treatment initiation at a comprehensive cancer center
Authors: Nonzee Narissa J. , Razavi Marianne , Dale William , Cai Lauren , Mercurio Annette , Gaytan Lorena , Lefkowitz Deborah , Kim Chrissy , Hernandez Terry , Morales Steven , Duque Danilo , Tergas Ana I. 
Published: March 2024

Abstract
Background: Delays in treatment initiation adversely impact cancer mortality and survival. To inform potential enhancements and targets for our existing oncology patient navigation program, we examined characteristics associated with timely treatment initiation among patients at a tertiary comprehensive cancer center that serves four diverse counties in Southern California.
Methods: We performed a retrospective analysis of patients newly diagnosed with non-hematological cancers between January 2020 and June 2023. Using electronic medical record data, we used a multivariable Cox proportional model to examine the association between patient demographic and clinical characteristics and time to treatment initiation (time between first encounter and start of definitive treatment) within a clinical benchmark of 3 months. A hazard ratio (HR)&gt;1 indicates shorter (faster) time to treatment initiation while a HR&lt;1 indicates a longer (slower) time.
Results: Our sample included 9,148 patients, who were predominantly &lt;65 years (57%), female (61%), married or with a partner (64%), and retired or unemployed (56%); 50% were non-White. In multivariable analyses, patient’s age, primary language, employment status, cancer diagnosis type, and first treatment type were significant determinants of time to treatment initiation. Faster treatment initiation was observed among patients ages &gt;=75 vs &lt;65 years (HR=1.36, 95% CI 1.23 - 1.52). Among the primary languages spoken in our sample (Spanish, Chinese, Korean, Vietnamese, among others), patients who spoke Armenian vs English also had shorter time to treatment (HR=1.64, 95% CI 1.32 - 2.04). By contrast, longer time to treatment initiation was associated with patients who were retired or disabled vs employed full-time (HR=0.85, 95% CI 0.78 - 0.94, and HR=0.70, 95% CI 0.59 - 0.83, respectively) and underwent radiation or oral chemotherapy vs chemo-infusion (HR=0.65, 95% CI 0.57 - 0.74, and HR=0.82, 95% CI 0.76 - 0.89, respectively). With the exception of melanoma, all diagnoses had a longer time to treatment compared with neuro-oncology. In our multivariable model, sex, marital status, race and ethnicity, and receipt of at least one navigation encounter were not significant determinants.
Conclusions: In our study, which overlapped the early stages of the COVID-19 pandemic, findings highlight opportunities to enhance navigation delivery, especially for certain subpopulations, diagnoses, and treatment types with complex scheduling and coordination needs. Future research will explore navigation intensity and other process and clinical outcomes modifiable through navigation.
Citation Format: Narissa J. Nonzee, Marianne Razavi, William Dale, Lauren Cai, Annette Mercurio, Lorena Gaytan, Deborah Lefkowitz, Chrissy Kim, Terry Hernandez, Steven Morales, Danilo Duque, Ana I. Tergas. Determinants of time to cancer treatment initiation at a comprehensive cancer center [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2237.