A new study found a low rate of cancer recurrence at the nipple-areola complex (NAC) in patients with breast cancer who underwent nipple-sparing mastectomy (NSM). Several characteristics of the tumor were associated with recurrence risk, including histologic grade and the presence of HER2-positive disease.
NSM is characterized by preservation of the entire NAC and breast skin envelope despite the removal of the mammary tissue during mastectomy.
“The main concern associated with NSM is the risk of local cancer recurrence at the retained NAC consequent to occult nipple involvement,” wrote study authors led by Zhen-Yu Wu, MD, of the Asan Medical Center at the University of Ulsan College of Medicine in Seoul, South Korea. “Because increasing numbers of patients with breast cancer are selecting NSM, it is important to identify the incidence of cancer recurrence at the NAC after NSM, describe the associated factors, and determine its association with prognosis.”
The authors analyzed outcomes from a retrospective cohort of 962 breasts from 944 patients who underwent NSM and immediate breast reconstruction for invasive breast cancer at the Asan Medical Center between 2003 and 2015. The results were published online ahead of print on August 28 in JAMA Surgery.
The patients had a median age at diagnosis of 43 years. They were followed for a median of 85 months, during which time there were 39 cases (4.1%) of cancer recurrence at the NAC as the first event after NSM (this excluded recurrences at the NAC found after a locoregional recurrence or distant metastases). The five-year cumulative incidence of NAC recurrence was 3.5%. In comparison, the five-year cumulative incidence of local recurrence at other locations other than the NAC was 3.4%. The median time from surgery to recurrence at the NAC was 35 months.
Several factors were independently associated with recurrence at the NAC on a multivariate analysis. Patients with hormone receptor-negative/HER2-positive tumors had a higher risk of recurrence at the NAC, with a hazard ratio of 3.051 (95% CI, 1.194–7.796; P = 0.02). High histologic grade was also associated with NAC recurrence, with an HR of 2.641 (95% CI, 1.132–6.160; P = 0.03), as was the presence of extensive intraductal component, with an HR of 3.338 (95% CI, 1.262–8.824; P = 0.02).
All 39 patients with recurrence at the NAC were alive at the last follow-up; they were followed after the recurrence for a mean of 51 months. The 10-year overall survival rate was 100% among those with NAC recurrence, and 94.5% among those without such a recurrence. There was no significant difference between those with and without NAC recurrence with regard to distant metastasis-free survival and OS.
“These findings suggest that factors should be considered when planning for NSM,” the authors wrote. “Most patients with cancer recurrence at the NAC had a favorable prognosis after receiving appropriate comprehensive treatment. As more patients with breast cancer undergo NSM, these data may be useful in estimating a prognosis for cancer recurrence at the NAC and guiding management decisions.”