Eligibility for NSM has expanded to include women with higher body mass index and larger breasts, with no increase in nipple loss due to ischemia. Rates of positive subareolar margins have decreased over time, even though NSM is being performed more frequently for cancer, suggesting improved patient selection.

Women with atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), lobular carcinoma in situ (LCIS), and severe ADH are at increased risk of breast cancer, but a systematic quantification of this risk and the efficacy of chemoprevention in the clinical setting is still lacking. The objective of this study is to evaluate a woman's risk of breast cancer based on atypia type and to determine the effect of chemoprevention in decreasing this risk. Review of 76,333 breast pathology reports from three institutions within Partners Healthcare System, Boston, from 1987 to 2010 using natural language processing was carried out. This approach identified 2,938 women diagnosed with atypical breast lesions. The main outcome of this study is breast cancer occurrence. Of the 2,938 patients with atypical breast lesions, 1,658 were documented to have received no chemoprevention, and 184/1,658 (11.1 %) developed breast cancer at a mean follow-up of 68 months. Estimated 10-year cancer risks were 17.3 % with ADH, 20.7 % with ALH, 23.7 % with LCIS, and 26.0 % with severe ADH. In a subset of patients treated from 1999 on (the chemoprevention era), those who received no chemoprevention had an estimated 10-year breast cancer risk of 21.3 %, whereas those treated with chemoprevention had a 10-year risk of 7.5 % (p < 0.001). Chemoprevention use significantly reduced breast cancer risk for all atypia types (p < 0.05). The risk of breast cancer with atypical breast lesions is substantial. Physicians should counsel patients with ADH, ALH, LCIS, and severe ADH about the benefit of chemoprevention in decreasing their breast cancer risk.

No abstract

Breast cancer in young women is associated with an aggressive tumor biology and higher risk of recurrence. Pathologic complete response (pCR) after neoadjuvant therapy has been shown to be a surrogate marker for disease-free survival (DFS) and overall survival (OS), but the association between pCR and survival outcomes in young women with breast cancer is not well described. This study included women aged ≤40 years at diagnosis who received neoadjuvant chemotherapy (NAC) for stage II-III invasive breast cancer between 1998 and 2014 at Massachusetts General Hospital. Outcomes were compared between patients who achieved pCR (ypT0/is, ypN0) and those with residual disease. A total of 170 young women were included in the analytical data set, of which 53 (31.2%) achieved pCR after NAC. The 5-year DFS rate for patients with and without pCR was 91% versus 60%, respectively (<.01), and the OS rate was 95% versus 75%, respectively (<.01). Among patients with pCR, no difference was seen in OS irrespective of baseline clinical stage (=.6), but among patients with residual disease after NAC, a significant difference in OS based on baseline clinical stage was observed (<.001). Our results suggest pCR after NAC is strongly associated with significantly improved DFS and OS in young women with breast cancer, and perhaps even more so than baseline stage. However, the significantly higher mortality for patients who did not attain pCR highlights the need for better therapies, and the neoadjuvant trial design could potentially serve as an efficient method for rapid triage and escalation/de-escalation of therapies to improve outcomes for young women with breast cancer.

NSM in BRCA1/2 carriers is associated with a low rate of complications and locoregional recurrence but these patients require long-term follow-up in both the cancer and risk-reduction setting.