Locoregional breast cancer recurrence is becoming less frequent. The range of treatment options and the pace of change, however, make it difficult to make treatment decisions when recurrence occurs, according to experts speaking at the 2017 San Antonio Breast Cancer Symposium in San Antonio, Texas, on December 5, 2017.
Locoregional recurrence is a potentially deadly “early warning sign” for patients with breast cancer, said Irene Wapnir, MD, professor of surgery at the Stanford University School of Medicine in Palo Alto, California.1
“The risk of developing distant metastasis and death after a locoregional recurrence of breast cancer is high,” she explained. “Locoregional recurrences in the skin, chest wall, breast tissue, or nodes usually represent progression of occult disease that persisted after treatment of the primary tumor.”
But there are exceptions, Dr Wapnir noted: some breast tumors, including some ipsilateral breast tumor recurrences (IBTRs), represent “de novo” disease, not stemming from persisting, post-treatment microscopic primary tumors.
In the 1980s and 1990s, the 10-year cumulative risks of IBTR after breast-conserving surgery (BCS) in clinical trial patient populations ranged from 2.6% to 4.7% for lymph node-negative cancer and from 4.8% to 10% in node-positive patients, Dr Wapnir said.
The median intervals from primary tumor to isolated locoregional recurrence for estrogen receptor (ER)-negative and ER-positive tumors are 3.6 years and 6.8 years, respectively.
Lumpectomy for node-negative patients is associated with a nearly 40% IBTR rate before 24 months post-surgery, compared with 12.5% for other types of locoregional recurrence, as well as a 72.7% IBTR rate and a 49.2% rate of other locoregional recurrences after 48 months, Dr Wapnir said.
In a recent meta-analysis of data from 88 clinical trials representing nearly 63,000 patients, the risk of locoregional recurrence among women with T1-T2 ER-positive breast cancer without nodal involvement was similar for patients undergoing BCS and those undergoing mastectomy (6% to 7% for BCS at 20 years post-surgery and 4% among women who underwent mastectomy).2 The overall risk of distant metastasis after locoregional recurrence ranged from 10% to 41%, depending on nodal status at the time of locoregional recurrence and tumor grade.