A new study published by Minami et al in the Journal of the American College of Surgeons found that longer time from diagnosis to surgical treatment did not lower overall survival in women with early-stage breast cancer. These findings may be reassuring for women with early-stage breast cancer who were forced to delay surgery due to the COVID-19 pandemic. The researchers also found no survival decrease with operative delays in women with estrogen-sensitive, early-stage breast cancer who received neoadjuvant endocrine therapy.
Patients with estrogen receptor (ER)-positive breast cancer typically receive antiestrogen therapy after surgical removal of the tumor or breast. However, endocrine therapy was recommended nationwide as the initial treatment of ER-positive breast cancer during pandemic-related surgical delays, said lead study author Christina Minami, MD, MS, an associate surgeon at Brigham and Women's Hospital.
Christina Minami, MD, MS
“Usually we take these patients with very small tumors directly to surgery, so it is a big change in practice to first put those patients on tamoxifen or an aromatase inhibitor,” explained Dr. Minami. “What we can say from our findings is that despite the delay in surgical therapy, because [patients] were on neoadjuvant endocrine therapy, we do not think that … survival will at all be impacted.”
The study included data from nearly 379,000 patients in two groups: one with ductal carcinoma in situ, and the other with small invasive tumors—stage I and limited stage II—that had not spread to nearby lymph nodes and were ER-positive.
Representative of Patients Who Postponed Surgery Due to COVID-19
These groups, Dr. Minami said, represent most patients with breast cancer who needed to postpone their nonurgent operations early in the COVID-19 outbreak according to the surgical prioritization recommendations of the COVID-19 Pandemic Breast Cancer Consortium. In March, the Consortium recommended neoadjuvant endocrine therapy for patients with ER-positive ductal carcinoma in situ and ER-positive, invasive early-stage breast cancer while they waited for their operations. At that time, the Consortium included the American Society of Breast Surgeons, the National Accreditation Program for Breast Centers, the National Comprehensive Cancer Network, the American College of Surgeons Commission on Cancer, and the American College of Radiology.
To better understand the ramifications of these surgical delay tactics, the researchers conducted this study using the National Cancer Database and analyzed data for 378,839 patients with early-stage breast cancer treated from 2010 to 2016. The researchers evaluated whether longer time to surgical treatment up to 1 year after diagnosis had an association with final pathologic staging of the cancer or with 5-year overall survival.
In women with invasive early-stage breast cancer, a longer time to the initial surgery showed no association with pathologic upstaging, the researchers reported. Women with ER-positive ductal carcinoma in situ, however, had a slightly increased odds of pathologic upstaging with a surgical delay exceeding 60 days. Patients whose ductal carcinoma in situ was ER-negative had a higher risk of upstaging only if they underwent an operation more than 120 days after diagnosis; they had an odds ratio of 1.36 compared with patients who underwent surgical treatment within the first 60 days.
This increase in upstaging among patients with ductal carcinoma in situ had no impact on their overall survival, said Dr. Minami. She stressed, however, that the patient population in their study differs from the patients who received neoadjuvant endocrine therapy during the COVID-19 pandemic. Before the pandemic, neoadjuvant endocrine therapy was not widely used for patients in the United States with early-stage, ER-positive breast cancer. Study participants who received neoadjuvant endocrine therapy from 2010 to 2016 did so for specific reasons, such as older age and coexisting illnesses, whereas in the pandemic, neoadjuvant endocrine therapy recipients were “almost an unselected population,” according to Dr. Minami.
She added that although the researchers used “the best data currently available to study the possible outcomes of oncologic surgical delays,” determination of the actual impact of COVID-19–related surgical delays requires study in patients treated during this time.
Elizabeth Mittendorf, MD, PhD, FACS
Despite this study limitation, senior study author Elizabeth Mittendorf, MD, PhD, FACS, Professor of Surgery at Brigham and Women's Hospital, said she has found the study findings helpful to share with her patients who experienced surgical delays.
“We can tell our patients they can still expect an excellent prognosis from their early-stage hormone receptor–positive cancer and that their excellent prognosis is not negatively impacted by this delay they have experienced,” concluded Dr. Mittendorf.
Disclosure: For full disclosures of the study authors, visit journalacs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.