Impact of great circle distance on breast cancer survival in NCDB.

Abstract

e13833 Background: Timeliness of breast cancer (BC) care, defined as initiation of treatment within 60 days of diagnosis, has a significant impact on survival. Barriers can cause delays and propagate disparities. Distance from the treatment facility may pose a significant delay to initiation of treatment and should be evaluated in relation to BC survival. We hypothesized that larger great circle distance (GCD), or distance from patient residence to treatment facility, leads to delayed timeliness of BC care and negatively impacts survival. Methods: We analyzed the National Cancer Database (NCDB) for primary BC cases diagnosed between 2004 and 2021. Demographic variables were captured. GCD was categorized as <10 miles, 10.1–20 miles, and > 20 miles. Chi-squared tests were used to assess the relationship between time to first treatment (surgery, chemotherapy, radiation) and GCD. Kaplan-Meier curves were utilized to evaluate overall survival, stratified by GCD and the first treatment received. Log-rank tests were used for comparison. Negative binomial regression models were used to evaluate associations between time-to-first treatment (in days) and GCD, with and without adjustments for social and clinical factors. Statistical significance was set at a p-value threshold of < 0.05; all tests were two-tailed. Results: The final cohort consisted of 283,166 BC patients. Surgery was the most common first treatment (n = 237,761, 84%). Half of the patients had a GCD < 10 miles of the treatment facility (n = 150,036; 53%), 66,506 (23%) lived between 10.1 and 20 miles, and 66,624 (24%) lived greater than 20 miles away. Increasing GCD was significantly associated with longer time to surgery (p < 0.01). However, overall survival was significantly worst for patients with GCD<10 miles and best for patients with GCD between 10.1 and 20 miles (p < 0.001) when receiving surgery or chemotherapy as first treatment; no difference was observed when radiation was first treatment (p = 0.41). Compared to non-Hispanic White patients, non-Hispanic Black and Hispanic patients experienced 20% (95% CI: 1.19, 1.21) and 15% (95% CI: 1.12, 1.18) longer delays to surgery, respectively, translating to 1.2 days longer to surgery. These differences were also observed in adjusted models for time-to-first chemotherapy and time-to-first radiation. Conclusions: Race and ethnicity were associated with increased time to surgery. Although shorter GCD was associated with shorter time to first treatment, survival was significantly worse for patients with GCD <10 miles. This may be attributable to factors related to neighborhood context surrounding the treatment facility.