Time to treatment initiation (TTI) in patients with colorectal cancer and liver metastases.

3568 Background: In colorectal cancer (CRC), the liver represents a common site of metastatic disease, and patients with colorectal liver metastases (CRLM) may sometimes still achieve surgical resection of hepatic metastases. In oncology, delays initiating cancer treatment usually correspond with worse outcomes, yet factors associated with time to treatment initiation (TTI) in patients with CRLM remain unstudied. Methods: We utilized the National Cancer Database (NCDB) to identify adults (≥18 years old) with confirmed CRLM diagnosed between 2010-2021. We defined TTI as the number of days between cancer diagnosis and the first non-surgical treatment (radiation, immune, or chemotherapy). We excluded cases in which TTI equaled zero or exceeded 120 days. We compared median TTI across sociodemographic (i.e., age, race, income) and clinical (i.e., primary tumor site, tumor grade, comorbidities [Charlson-Deyo score]) factors reported in the NCDB using a non-parametric Kruskal-Wallis test. Results: We included 15,456 patients with CRLM diagnosed between 2010-2021 (55.1% of patients age < 60 years, 44.8% female, 76.3% White, 12.3% Black, 6.3% Hispanic, 3.6% Asian, 0.3% American Indian, 1.2% Other). The median (m) TTI for this cohort was 41 days, with TTI values trending down between subsequent years from 2010 (m = 45) to 2020 (m = 38) until 2021 (m = 41). We found significant differences (p < 0.0001) in median TTI across sociodemographic and clinical factors, as detailed in the following sentences. Advanced age (80+) had longer TTI (m = 53), compared with young patients (m = 33). For race/ethnicity, Black patients (m = 47) had the longest TTI, while Asian patients had the shortest (m = 39). Patients earning in the highest income quartile had the shortest TTI (m = 38) compared with those earning in the lowest quartile (m = 44). Patients living in ZIP codes with the highest quartile of high school diploma attainment had the lowest TTI (m = 38) compared with those in the lowest quartile (m = 43). TTI varied significantly by reported geographic location, with the Pacific region having the lowest (m = 37) and the East South Central having the highest TTI (m = 44). Patients with Charlson-Deyo comorbidity scores of 2 had the highest TTI (m = 48) and patients with scores of 0 the lowest (m = 41). Right sided primary tumor locations (m = 46) had longer TTI compared to left sided primary sites (m = 39). Tumor sizes greater than 6 cm (m = 45) received treatment later than tumor sizes less than 2 cm (m = 35). Lower grade tumors had longer TTI (m = 34) compared to high grade tumors (m = 28). Conclusions: In our study of patients with CRLM in the NCDB, the median TTI was just under 6 weeks. Our findings suggest that certain patient groups may be at risk of experiencing delays in care. These results could help to motivate and inform future efforts to enhance care delivery and access for patients with CRLM.