Background: Sentinel lymph node biopsy (SLNB) has emerged as the standard procedure to replace axillary lymph node dissection (ALND) in breast cancer (BC) patients undergoing neo-adjuvant chemotherapy (NAC). SLNB is accepted in clinically node-negative (cN0) patients; however, its role in clinically node-positive (cN+) patients is debatable. Methods: We performed a retrospective analysis of BC patients undergoing NAC and SLNB. Our aim was to evaluate the clinical significance of SLNB in the setting of NAC. This was accomplished by comparing the characteristics and oncological outcomes between cN0 and cN+ patients prior to NAC and type of axillary surgery. Results: A total of 291 patients were included in the analysis: 131 were cN0 and 160 were cN+ who became ycN0 after NAC. At a median follow-up of 43 months, axillary recurrence occurred in three cN0 (2.3%) and two cN+ (1.3%) patients. However, there were no statistically significant differences in oncological outcomes (disease-free survival, distant disease-free survival, overall survival, and breast-cancer-specific survival) between cN0 and cN+ patients nor between patients treated with SLNB only or ALND. Conclusions: SLNB in the setting of NAC is an acceptable procedure with a general good prognosis and low axillary failure rates for both cN0 and cN+ patients.

Backgrounds: This study compares the long-term outcomes of axillary lymph node dissection (ALND) versus sentinel lymph node biopsy (SLNB) in clinically node-positive (cN+) breast cancer (BC) patients treated with neoadjuvant therapy (NAT).Methods: We conducted a retrospective analysis of 322 cN+ BC patients who became clinically node-negative (ycN0) post-NAT. Patients were categorized based on the final type of axillary surgery performed: ALND or SLNB. Recurrence-free survival (RFS), distant disease-free survival (DDFS), overall survival (OS), and breast cancer-specific survival (BCSS) were evaluated and compared between the two groups. Results: Patients in the SLNB group had significantly better 3-, 5-, and 10-year RFS, DDFS, OS, and BCSS compared to those in the ALND group. The SLNB group also had a higher proportion of patients achieving pathologic complete response (pCR). Multivariate analysis identified pCR, ypN0 status, and SLNB as favorable prognostic factors for all survival metrics. Axillary recurrence rates were low for both groups (0.6–2.1%). Conclusions: SLNB may be a safe and effective alternative to ALND for selected cN+ BC patients who convert to ycN0 after NAT. These findings suggest that careful patient selection is crucial, and further research is needed to validate these results in more comparable populations.

Background: Loco-regional therapy (LRT) in de novo metastatic breast cancer (MBC) has been investigated in several clinical trials, with heterogeneous and conflicting results. Methods: We conducted a retrospective study of de novo MBC patients treated with front-line chemotherapy (FLC) followed by LRT of the primary tumor. Our aims were to evaluate the characteristics, treatment, and oncological outcomes in terms of progression-free survival (PFS), distant progression-free survival (DPFS), and overall survival (OS) of de novo MBC. We also investigated possible subgroups of patients with better outcomes according to menopausal status, biological sub-type, location, number of metastases, and radiologic complete response after FLC. Results: We included 61 patients in the study. After a median follow-up of 55 months, disease progression occurred in 60.7% of patients and 49.2% died. There were no significant differences in PFS, DPFS, and OS between different subgroups of de novo MBC patients. A trend toward better PFS and DPFS was observed in triple-positive tumors, without a statistically significant difference in OS. Conclusions: No specific subgroup of de novo MBC patients showed a statistically significant survival advantage after FLC followed by LRT of the primary tumor.

Background: Neoadjuvant therapy (NAT) has become increasingly employed for the treatment of cT3-4 breast cancer (BC), enabling breast-conserving surgery (BCS) in cases traditionally considered for mastectomy. This study aims to identify predictors for breast conservation post-NAT and to evaluate whether BCS influences long-term oncological outcomes. Methods: We retrospectively analyzed data from patients with cT3-4 BC who received NAT at the Breast Unit of IRCCS Humanitas Research Hospital, Milan, Italy, from October 2009 to April 2020. Surgical outcomes and long-term oncological results, such as disease-free survival (DFS), distant DFS (DDFS), overall survival (OS), and BC-specific survival (BCSS), were compared between the BCS and mastectomy groups. Results: Among 114 patients analyzed, 37 (32.5%) underwent BCS, and 77 (67.5%) had a mastectomy. The key predictors for opting for BCS included absence of vascular invasion, reduced tumor size post-NAT, and achieving ypT0 status. No significant differences in DFS, DDFS, OS, and BCSS were observed between the two surgical groups (log-ranks, p = 0.520, p = 0.789, p = 0.216, p = 0.559, respectively). Conclusions: BCS after NAT is a feasible and safe option for patients with cT3-4 BC, without adversely affecting long-term oncological outcomes. Identifying predictors of breast conservation can guide surgical decision-making, ensuring that patients receive optimal treatment.

Backgrounds: The majority of breast cancer (BC) patients treated with neo-adjuvant chemotherapy (NAC) achieves a pathologic partial response with different patterns of residual disease. No clear correlation between these patterns and oncological results was described. Our aims were to define the predictive factors for different patterns of residual disease and compare the outcomes between the scattered versus the circumscribed pattern. Methods: We reviewed 219 postoperative surgical specimens. Patients were divided into two groups: scattered versus circumscribed. Disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS) were analyzed. Results: The scattered and circumscribed patterns were assessed in 111 (50.7%) and 108 (49.3%) patients. Two independent predictive factors for the circumscribed pattern were identified: discontinuation of NAC cycles (p = 0.011), and tumor size post-NAC >18 mm (p = 0.022). No difference was observed in terms of DFS and DDFS. Patients with the scattered pattern exhibited a statistically significant better OS. Discontinuation of NAC cycles, tumor size >18 mm, triple-negative BC, and ypN+ were associated with increased recurrence and poorer survival. Conclusions: Discontinuation of NAC cycles and tumor size are independent factors associated with patterns of residual disease. The scattered pattern presents better survival. Understanding the relationship between NAC, the residual pattern, and differences in survival outcomes offers the potential to optimize the therapeutic approaches.

Backgrounds: Neoadjuvant therapy (NAT) is a cornerstone in the management of breast cancer (BC), enabling tumor downstaging and improved surgical options. Methods: This study retrospectively analyzed 607 BC patients treated with NAT and surgery at IRCCS Humanitas Research Hospital, Milan, Italy, to compare long-term oncologic outcomes of breast-conserving surgery (BCS) versus mastectomy. Patient demographics, tumor characteristics, and treatment details were analyzed using descriptive statistics, logistic regression, and Cox proportional hazards models. Results: Of the 607 patients, 54.7% underwent BCS, and 45.3% had mastectomy. BCS was associated with significantly superior 10-year outcomes compared to mastectomy, including disease-free survival (DFS, 75.2% vs. 71.1%, p = 0.001), distant DFS (75.2% vs. 71.1%, p = 0.001), overall survival (OS, 82.9% vs. 78.1%, p = 0.002), and BC-specific survival (BCSS, 87.7% vs. 83.1%, p = 0.001). Pathologic complete response (pCR) emerged as a protective factor across all endpoints, while mastectomy was independently associated with worse BCSS (HR: 2.068, 95% CI: 1.016–4.210, p = 0.045). Conclusions: Our findings demonstrate the oncologic safety and potential superiority of BCS over mastectomy in NAT-treated BC patients, highlighting the importance of individualized surgical decision-making to optimize survival outcomes.