COVID-19 Pandemic Forces Changes in Breast Cancer Treatment

There have been significant modifications in breast cancer treatment due to the coroanvirus disease 2019 (COVID-19) pandemic, such as increased rates of neoadjuvant endocrine (NET) chemotherapy, genomic assay testing on core biopsies, and delays in planned surgeries, according to the results of a study presented at the 2020 San Antonio Breast Cancer Symposium, which was held virtually in December.

These modifications are consistent with the prioritization and treatment recommendations made by the COVID-19 Pandemic Breast Cancer Consortium.

During the study, investigators observed that a majority of patients with triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2 (HER2)-positive disease received guideline concordant neoadjuvant chemotherapy (NCT).

To get a clearer understanding of the rapid-care changes caused by the pandemic, the American Society of Breast Surgeons (ASBrS) developed a COVID-19 registry within the established Health Insurance Portability and Accountability Act-compliant Mastery of Breast Surgery Program to provide a snapshot of what has occurred in the field. Additionally, ASBrS developed the registry to support ongoing data entry and analysis and allow understanding of the impact of the pandemic on long-term breast cancer outcomes.

During the pandemic, many hospitals stopped some or all cancer surgeries to save personal protective equipment and minimize exposure. This, in turn, forced oncologic providers to quickly adjust patient treatment approaches.

For these reasons, investigators intended to describe the level of changes in patients with breast cancer that occurred in the initial months of the COVID-19 pandemic in the United States.

To assess these effects, the COVID-19-specific registry developed by ASBrS allowed surgeons to enter patient demographic data, as well as information on the patients' medical and surgical care. The data fields were then tracked to determine whether decisions made were the typical ones for that practice or modified due to the pandemic.

Data were entered by 154 surgeons from March 1 to June 17, 2020, for 1781 patients. Of the patients added to the registry, the mean age was 63 years; 78% were White, 10% were Black, and 6% were Hispanic. In terms of geographic distribution, the percentages ranged from 10.8% in the Northwest to 29.5% in the Northeast.

For initial consultations, 94.8% occurred in person and 5.2% took place via telephone or video. During the study period, approximately 1% (14) of patients tested positive for COVID-19.

The mean invasive tumor size for patients was 21.2 mm, and 15.7% of the tumors were node positive. Among the 1445 invasive breast cancer observed, 75% (1081) ere estrogen receptor (ER)-positive/HER2-negative, 13.5% (195) were HER2-positive, and 11.1% (160) were TNBC.

Of the cohort, patients with ductal carcinoma in situ (DCIS) comprised 18.2% (325). In 267 cases of ER-positive DCIS, 49% (131) of patients received primary surgery, whereas 49% (130) received NET. However, 95% (124) of NET use was a result of COVID-19.

A significant number (50/52) of patients with ER-negative DCIS underwent primary surgery, whereas NET due to COVID-19 was used in 45% (482) of patients, with just 5% (54) of NET being noted as a part of usual practice.

The investigators observed that age was not a significant factor in the use of NET (OR 0.99, 95% CI 0.97-1.01). They also found that patients in the Northeast and Southwest had the greatest use of NET because of COVID-19 when compared with usual NET use (ORs 14.4 and 4.6).

Among 216 patients observed in the study period, genomic assay testing was performed on the core biopsy, with 65% (141) of the tests conducted because of COVID-19. Of those patients who received genomic testing because of COVID-19, 116 (82%) had NET, 18 (13%) had NCT, whereas the rest received primary surgery. Surgery was delayed in 20% (96) of the 472 patients who received primary surgery due to COVID-19.

Among patients in the Northeast, there was a 2.1 times greater likelihood of a surgery being delayed due to COVID-19 compared with patients in the Midwest. There were also changes made to surgical plans because of the pandemic. The most common changes were converting from mastectomy to breast conservation (6% [27]) and from mastectomy with reconstruction to mastectomy without reconstruction (7% [34]).

REFERENCE

Wilke LG. Impact of the COVID-19 pandemic on the multidisciplinary management of breast cancer: initial analysis of the American Society of Breast Surgeons Mastery COVID-19 Registry. Presented at: 2020 San Antonio Breast Cancer Symposium; December 8-11, 2020; virtual.