Operative Delays Do Not Worsen Survival in Early Breast Cancer

By Will Boggs MD

August 13, 2020

NEW YORK (Reuters Health) - Increases in time from diagnosis to surgery do not affect overall survival in women with ductal carcinoma in situ (DCIS) or early-stage hormone-receptor-positive breast cancer treated with neoadjuvant endocrine therapy (NET), according to findings from the National Cancer Database (NCDB).

"Ultimately the surgical delays that DCIS and early-stage breast cancer patients suffer secondary to the COVID-19 pandemic will not change their overall excellent prognosis," Dr. Christina A. Minami of Dana-Farber/Brigham and Women's Cancer Center, in Boston, told Reuters Health by email.

During the COVID-19 pandemic, operations for DCIS and early-stage breast cancer have commonly been deferred, and NET has been recommended as the preferred strategy for women with estrogen-receptor-positive (ER+) DCIS and for women with early-stage ER+ invasive breast cancer. How time to surgery (TTS) affects breast-cancer outcomes in these very early stage patients remains unclear.

Dr. Minami and colleagues used NCDB data from 2010-2016 to examine the association between TTS and pathological staging, as well as its impact on overall survival and extent of breast surgery, in women with DCIS or early-stage (cT1-2N0) ER+ disease.

The study included close to 100,000 women with DCIS and more than 222,000 with cT1N0 and 56,000 with cT2N0 disease; 98.2% of women with DCIS underwent surgery in the first 120 days after diagnosis, with 99.4% of women with cT1N0 and 99.1% of women with cT2N0 disease having primary surgery.

Only 0.7% of women with cT1N0 disease and 3.3% of women with cT2N0 disease underwent NET. Of these, 59.6% and 30.9%, respectively, underwent surgery within 120 days of diagnosis, the researchers report in Journal of the American College of Surgeons.

Among women with DCIS, increased TTS was associated with 15% greater odds of pathological upstaging for those with ER+ disease whose TTS was 60-120 days, 44% greater for those with ER+ disease whose TTS was >120 days, and 36% greater for those with ER- disease whose TTS was >120 days, compared with women whose TTS was <60 days.

In contrast, TTS was not significantly associated with pathological upstaging among women with early-stage breast cancer who underwent primary surgery or among those who received NET.

Overall survival did not differ by TTS among women with DCIS or among women who underwent NET. In the primary-surgery group there was a slight decrease in overall survival associated with longer TTS both in women with cT1N0 (96.7% with TTS <60 days vs. 94.7 with TTS >120 days) and in women with cT2N0 (92.6% vs. 90.8%).

Mastectomy rates increased with longer TTS among women with DCIS and among those with cT1-T2N0 disease who underwent primary surgery, but in the NET groups, mastectomy rates decreased with increasing TTS.

"It's difficult to know what drove (these findings), as there are a lot of factors that we couldn't adjust for in this dataset that could be associated with both surgical delays and worse oncologic outcomes," Dr. Minami said. "Certainly, it speaks to the wisdom of placing these patients on neoadjuvant endocrine therapy during the pandemic and the need to understand how to mitigate unduly long surgical delays under normal circumstances."

"It bears emphasizing that the population of patients placed on neoadjuvant endocrine therapy and those who suffered surgical delays in this dataset are likely very different from those who suffered delays during the COVID-19 pandemic," she said. "It's helpful to have the results of this analysis to counsel our patients now, but we do need to make sure we follow our patients whose oncologic care was affected by the pandemic to understand the ramifications of our practice changes."

Dr. Giuseppe Curigliano of Istituto Europeo di Oncologia and the University of Milan, in Italy, who recently reviewed recommendations for triage, prioritization and treatment of breast-cancer patients during the COVID-19 pandemic, told Reuters Health by email, "What is very reassuring is that no survival differences in patients with DCIS or early-stage ER-positive breast cancer on NET were noted by time to surgery."

"In order to better stratify the risk of pathological upstaging in both DCIS and invasive small tumors, genomic prognostic signatures may help us to identify those patients with DCIS who are candidates for early surgery or those with invasive cancer who may benefit from neoadjuvant chemotherapy (if classified high risk)," he said. "The most important message is that a multidisciplinary team evaluation should drive decisions in any single patient case."

SOURCE: https://bit.ly/2CgJskr Journal of the American College of Surgeons, online August 6, 2020.