308P - Impact of the COVID-19 (C19) pandemic on breast cancer (BC) treatment patterns in the US

Background

The C19 pandemic profoundly impacted access to care and practice patterns. We examine the impact of C19 on treatment modality selection and time to treatment initiation (TTI) among patients with early-stage BC.

Methods

Patients with clinical stage I-III BC diagnosed 2018-2021 were identified in the National Cancer Database (NCDB). Patients were categorized based on year of diagnosis as pre-C19 (2018-2019), early-C19 (2020), and late-C19 (2021). We compared TTI based on first treatment modality (surgery, chemotherapy, radiation, or endocrine therapy) using Wilcoxon rank sum test and implemented logistic regression models to evaluate factors associated with TTI delays >60 days (OR, 95%CI).

Results

We included 567,942 patients. There was a 7.6% decrease in number of BC cases in NCDB from pre- to early-C19, with 8.2% fewer cases of stage I diagnosed in 2020. There were otherwise no major differences in the proportion of diagnosed cases based on age, race, or subtype. The use of neoadjuvant endocrine therapy increased from 4.2% pre-C19 to 7.7% in early-C19. Fewer patients underwent surgery as first treatment (82.4%, 77.1%, and 75.4% in pre-, early-, and late-C19, respectively). Among patients undergoing surgery as initial treatment, the median time to surgery increased from 34 days in pre-and early-C19 to 41 days in late-C19. The proportion of patients experiencing delays in TTI (any modality) was 14.7%, 13.6%, and 19.5% in pre-, early- and late-C19 periods, respectively. In multivariable analysis, the late-C19 period was associated with significant increased risk of delays in treatment initiation (OR 1.39, 95% CI 1.37-1.42) compared to pre-C19. Factors associated with increased risk of delayed treatment initiation included Black race, Hispanic ethnicity, comorbidities, public insurance, or no insurance.

Conclusions

There was a small decrease in BC cases in NCDB during the early-C19 pandemic, with proportionally less stage I cases. There was a change in the initial treatment of choice and an increase in treatment delays, particularly during late-C19, likely due to the impact of the pandemic on the healthcare system. Patients belonging to vulnerable groups were more likely to experience delays in treatment initiation.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Breast Cancer Research Foundation (BCRF-23-190); Susan G. Komen (SAC150061).

Disclosure

All authors have declared no conflicts of interest.