Course: Comparison of Use of Neoadjuvant Systemic Treatment for Breast Cancer and Short-term Outcomes Before vs During the COVID-19 Era in Ontario, Canada
CME Credits: 1.00
Released: 2022-08-02
Key Points
Question Did the use of neoadjuvant-intent systemic therapy for patients with breast cancer change after the emergence of COVID-19 in Ontario, Canada?Findings In this cohort study including 10,920 patients, the use of neoadjuvant-intent chemotherapy and hormonal treatment increased during the COVID-19 era, but there was substantial regional variability. Bridging hormonal therapy was a more common adaptation to cancer treatment in the COVID-19 era than neoadjuvant chemotherapy; neoadjuvant-intent systemic treatment was not associated with short-term outcomes in the COVID-19 era.
Meaning These findings suggest that patients with breast cancer were more likely to receive neoadjuvant-intent systemic treatment in the COVID-19 era to offset delays in surgical capacity.
Abstract
Importance In response to an increase in COVID-19 infection rates in Ontario, several systemic treatment (ST) regimens delivered in the adjuvant setting for breast cancer were temporarily permitted for neoadjuvant-intent to defer nonurgent breast cancer surgical procedures.Objective To examine the use and compare short-term outcomes of neoadjuvant-intent vs adjuvant ST in the COVID-19 era compared with the pre–COVID-19 era.
Design, Setting, and Participants This was a retrospective population-based cohort study in Ontario, Canada. Patients with cancer starting selected ST regimens in the COVID-19 era (March 11, 2020, to September 30, 2020) were compared to those in the pre–COVID-19 era (March 11, 2019, to March 10, 2020). Patients were diagnosed with breast cancer within 6 months of starting systemic therapy.
Main Outcomes and Measures Estimates were calculated for the use of neoadjuvant vs adjuvant ST, the likelihood of receiving a surgical procedure, the rate of emergency department visits, hospital admissions, COVID-19 infections, and all-cause mortality between treatment groups over time.
Results Among a total of 10,920 patients included, 7990 (73.2%) started treatment in the pre–COVID-19 era and 7344 (67.3%) received adjuvant ST; the mean (SD) age was 61.6 (13.1) years. Neoadjuvant-intent ST was more common in the COVID-19 era (1404 of 2930 patients [47.9%]) than the pre–COVID–19 era (2172 of 7990 patients [27.2%]), with an odds ratio of 2.46 (95% CI, 2.26-2.69; P?<?.001). This trend was consistent across a range of ST regimens, but differed according to patient age and geography. The likelihood of receiving surgery following neoadjuvant-intent chemotherapy was similar in the COVID-19 era compared with the pre–COVID-19 era (log-rank P?=?.06). However, patients with breast cancer receiving neoadjuvant-intent hormonal therapy were significantly more likely to receive surgery in the COVID-19 era (log-rank P?<?.001). After adjustment, there were no significant changes in the rate of emergency department visits over time between patients receiving neoadjuvant ST, adjuvant ST, or ST only during the ST treatment period or postoperative period. Hospital admissions decreased in the COVID-19 era for patients who received neoadjuvant ST compared with adjuvant ST or ST alone (P for interaction?=?.01 for both) in either setting.
Conclusions and Relevance In this cohort study, patients were more likely to start neoadjuvant ST in the COVID-19 era, which varied across the province and by indication. There was limited evidence to suggest any substantial impact on short-term outcomes.
Educational Objective
To identify the key insights or developments described in this article
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