Increase in Utilization of Nipple-Sparing Mastectomy for Breast Cancer: Indications, Complications, and Oncologic Outcomes.

BACKGROUND: Nipple-sparing mastectomy (NSM) is increasingly performed for invasive breast cancer. Growing evidence supporting the oncologic safety of NSM has led to its widespread use and broadened indications. In this study, we examine the indications, complications, and long-term outcomes of therapeutic NSM. METHODS: From 2003 to 2016, women undergoing NSM for invasive cancer or ductal carcinoma in situ (DCIS) were identified from a prospectively maintained database. Patient and disease characteristics were compared by procedure year, while complications were compared by procedure year using generalized mixed-effects models accounting for a random surgeon effect. Overall survival and time to recurrence were examined. RESULTS: Of the 467 therapeutic NSMs, 337 (72%) were invasive cancer, 126 (27%) were DCIS, and 4 (1%) were phyllodes tumors. Median age was 45 years (range 24-75) and median follow-up among survivors was 39.4 months. Three hundred and fifty-seven (76.4%) cases were performed in 2011 or after. When comparing NSMs performed before and after 2011, there was a significant increase in NSMs performed for invasive tumors (58% vs. 77%; p < 0.001). There was no difference in family history, genetic mutations, smoking status, neoadjuvant chemotherapy, prior radiation, nodal involvement, or tumor subtype. Twenty-one (4.5%) nipple excisions were performed, of which 14 were performed for cancer at the nipple margin. Forty-four breasts (9.4%) had complications that required re-operation. Fifteen patients had locoregional recurrence or distant metastasis. CONCLUSIONS: NSM use for invasive carcinoma has doubled at our institution since 2011, while postoperative complications and recurrence rates remain low. Our experience supports the selective use of NSM in the malignant setting with careful patient selection.

Axillary Dissection and Nodal Irradiation Can Be Avoided for Most Node-positive Z0011-eligible Breast Cancers: A Prospective Validation Study of 793 Patients.

OBJECTIVE: To determine rates of axillary dissection (ALND) and nodal recurrence in patients eligible for ACOSOG Z0011. BACKGROUND: Z0011 demonstrated that patients with cT1-2N0 breast cancers and 1 to 2 involved sentinel lymph nodes (SLNs) having breast-conserving therapy had no difference in locoregional recurrence or survival after SLN biopsy alone or ALND. The generalizability of the results and importance of nodal radiotherapy (RT) is unclear. METHODS: Patients eligible for Z0011 had SLN biopsy alone. Prospectively defined indications for ALND were metastases in ≥3 SLNs or gross extracapsular extension. Axillary imaging was not routine. SLN and ALND groups and radiation fields were compared with chi-square and t tests. Cumulative incidence of recurrences was estimated with competing risk analysis. RESULTS: From August 2010 to December 2016, 793 patients met Z0011 eligibility criteria and had SLN metastases. Among them, 130 (16%) had ALND; ALND did not vary based on age, estrogen receptor, progesterone receptor, or HER2 status. Five-year event-free survival after SLN alone was 93% with no isolated axillary recurrences. Cumulative 5-year rates of breast + nodal and nodal + distant recurrence were each 0.7%. In 484 SLN-only patients with known RT fields (103 prone, 280 supine tangent, 101 breast + nodes) and follow-up ≥12 months, the 5-year cumulative nodal recurrence rate was 1% and did not differ significantly by RT fields. CONCLUSIONS: We confirm that even without preoperative axillary imaging or routine use of nodal RT, ALND can be avoided in a large majority of Z0011-eligible patients with excellent regional control. This approach has the potential to spare substantial numbers of women the morbidity of ALND.

Axillary dissection can be avoided in the majority of clinically node-negative patients undergoing breast-conserving therapy.

BACKGROUND: The extent to which ACOSOG Z0011 findings are applicable to patients undergoing breast-conserving therapy (BCT) is uncertain. We prospectively assessed how often axillary dissection (ALND) was avoided in an unselected, consecutive patient cohort meeting Z0011 eligibility criteria and whether subgroups requiring ALND could be identified preoperatively. METHODS: Patients with cT1,2cN0 breast cancer undergoing BCT were managed without ALND for metastases in <3 sentinel nodes (SNs) and no gross extracapsular extension (ECE). Patients with and without indications for ALND were compared using Fisher's exact and Wilcoxon rank sum tests. RESULTS: From August 2010 to November 2012, 2,157 invasive cancer patients had BCT. A total of 380 had histologic nodal metastasis; 93 did not meet Z0011 criteria. Of 287 with ≥1 H&E-positive SN (209 macrometastases), 242 (84 %) had indications for SN only. ALND was indicated in 45 for ≥3 positive SNs (n = 29) or ECE (n = 16). The median number of SNs removed in the SN group was 3 versus 5 in the ALND group (p < 0.0001). Age, hormone receptor and HER2 status, and grade did not differ between groups; tumors were larger in the ALND group (p < 0.0001). Of ALND patients, 72 % had additional positive nodes (median = 1; range 1-19). No axillary recurrences have occurred (median follow-up, 13 months). CONCLUSIONS: ALND was avoided in 84 % of a consecutive series of patients having BCT, suggesting that most patients meeting ACOSOG Z0011 eligibility have a low axillary tumor burden. Age, ER, and HER2 status were not predictive of ALND, and the criteria used for ALND (≥3 SNs, ECE) reliably identified patients at high risk for residual axillary disease.

Nipple-sparing mastectomy for breast cancer and risk-reducing surgery: the Memorial Sloan-Kettering Cancer Center experience.

BACKGROUND: Nipple-sparing mastectomy (NSM) has been gathering increased recognition as an alternative to more traditional mastectomy approaches. Initially, questions concerning its oncologic safety limited the use of NSM. Nevertheless, mounting evidence supporting the practice of NSM for both prophylactic and oncologic purposes is leading to its more widespread use and broadened indications. METHODS: Using a prospectively maintained database, we reviewed our experience of 353 NSM procedures performed in 200 patients over the past 10 years. RESULTS: The indications for surgery were: 196 prophylactic risk-reduction (55.5%), 74 ductal carcinoma in situ (DCIS) (20.8%), 82 invasive cancer (23.2%), and 1 phyllodes tumor (0.5%). The nipple areolar complex (NAC) was entirely preserved in 341 mastectomies (96.7%). There were 11 patients (3.1%) who were found to have cancer at the nipple margin, warranting further excision. A total of 69 breasts (19.5%) had some degree of skin desquamation or necrosis, but only 12 (3.3%) required operative debridement, of which 3 breasts (1%) necessitated removal of a breast implant. Also, 6 patients (2%) were treated for infection. Of the 196 prophylactic NSMs, 11 specimens (5.6%) were found to harbor occult cancer (8 DCIS and 3 invasive cancers). One patient who underwent NSM for invasive ductal carcinoma in 2006 developed metastatic disease to her brain. No other recurrences are attributable to the 353 NSMs. CONCLUSIONS: The trends demonstrate the increasing acceptance of NSM as a prophylactic procedure as well as for therapeutic purposes. Although NSM is not standard, our experience supports the selective use of NSM in both prophylactic and malignant settings.

Conservative mastectomies for breast cancer and risk-reducing surgery: the Memorial Sloan Kettering Cancer Center experience.

Demand for conservative mastectomies continues to increase as more patients choose to undergo breast reconstruction, often with simultaneous contralateral prophylactic mastectomy (CPM). In addition, the increasing use of risk-reducing surgery in high-risk groups has contributed to the increased use of these techniques. We have reviewed the indications and outcomes of a large group of patients undergoing nipple-sparing mastectomy (NSM) at this institution. In total, 728 nipple-sparing mastectomies (NSMs) were performed in 413 patients between 2000 and 2013, for treatment of breast cancer (n=269) or risk reduction (n=459). Of 728 NSMs performed, 177 (24.3%) were in patients known to have a BRCA1 or BRCA2 germline mutation, or a genetic variant of uncertain significance. There was an incidental finding of ductal carcinoma in situ (DCIS) or invasive carcinoma in 22 (4.8%) and 8 (1.7%) of 459 prophylactic NSMs, respectively. In addition, unexpected invasive carcinoma was found in 17 of 98 therapeutic NSMs (17.3%) performed for DCIS. At median follow-up of 49 months, there were no known cases of local recurrence and only one case of regional recurrence. Immediate breast reconstruction was performed in 409 patients, most of whom underwent tissue expander/implant based procedures (n=401). Although 273 breasts (37.5%) had some evidence of skin desquamation at follow-up, most resolved spontaneously with 47 breasts (6.5%) requiring debridement. Other complications included hematoma in seven breasts (1%) and wound infection in 31 breasts (4.3%). Expander/implant removal was required in 20 cases (2.8%). The nipple-areola complex (NAC) was subsequently excised in 10 of 728 breasts (1.4%) due to oncologic concerns following assessment of retroareolar tissue. NSM was successful in most patients with an acceptable complication rate and in few patients subsequently undergoing removal of the NAC. Patients requiring mastectomy for breast cancer or risk reduction may now benefit from conservative mastectomy techniques such as NSM, resulting in improved cosmesis and, possibly, a reduced psychological impact.

Risk-reducing mastectomy.

Mastectomy rates have significantly increased over the last decades, likely due to the rising trend of risk-reducing mastectomies (RRM) in the treatment and prevention of breast cancer. Growing evidence suggests that aggressive risk-reducing surgical strategies are only justified in high-risk breast cancer situations. Notably, in this selected cohort of women, prophylactic mastectomies offer evident benefit for local and contralateral disease control, and may also provide a survival benefit. Nevertheless, the extent of the increasing frequency of this operation is not explained by the broadening of the medical indications alone. Here we analyze the current evidence regarding RRM, its clinical practice, and possible explanations for the rising phenomenon of aggressive surgical locoregional control strategies.