Purpose: Neoadjuvant endocrine treatment (NET) has become a useful tool for the downstaging of luminal-like breast cancers in postmenopausal patients. It enables us to increase breast- conserving surgery (BCS) rates, provides an opportunity for us to assess in vivo NET effectiveness, and allows us to study any biological changes that may act as valid biomarkers. The purpose of this study was to evaluate the safety and effectiveness of NET, and to assess the role of Ki67 proliferation rate changes as an indicator of endocrine responsiveness. Methods: From 2016 to 2020, a single-institution cohort of patients, treated with NET and further surgery, was evaluated. In patients with Ki67 ≥ 10%, a second core biopsy was performed after four weeks. Information regarding histopathological and clinical changes was gathered. Results: A total of 115 estrogen receptor-positive (ER+)/HER2-negative patients were included. The median treatment duration was 5.0 months (IQR: 2.0–6.0). The median maximum size in the surgical sample was 40% smaller than the pretreatment size measured by ultrasound (p < 0.0001). The median pretreatment Ki67 expression was 20.0% (IQR: 12.0–30.0), and was reduced to 5.0% (IQR: 1.8–10.0) after four weeks, and to 2.0% (IQR: 1.0–8.0) in the surgical sample (p < 0.0001). BCS was performed on 98 patients (85.2%). No pathological complete responses were recorded. A larger Ki67 fold change after four weeks was significantly related to a PEPI score of zero (p < 0.002). No differences were observed between luminal A- and B-like tumors, with regard to fold change and PEPI score. Conclusions: In our cohort, NET was proven to be effective for tumor size and Ki67 downstaging. This resulted in a higher rate of conservative surgery, aided in therapeutic decision making, provided prognostic information, and constituted a safe and well-tolerated approach.

Purpose: Recently, authors have shown increasing interest in the emerging HER2-low subtype in breast cancer. These tumors are currently classified and treated as HER2-negative tumors. Neoadjuvant endocrine therapy (NET) has been used to achieve tumor downstaging and assess treatment response in postmenopausal women with low-grade luminal HER2-negative tumors. This study aimed to determine whether the response to NET was affected by low levels of HER2 expression in luminal tumors. Methods: The study was a single-centered retrospective investigation. Data were gathered from the medical records of patients from 2017 to 2023. All patients had luminal HER2-negative tumors and were treated with NET and subsequent surgery. Results: In total, 175 tumors were analyzed; 24.0% of the tumors were HER2-zero, 48.0% were HER2-low 1+, and 28.0% were HER2-low 2+. No significant differences were found when assessing NET response between the three groups, nor when evaluating tumor features. Response to NET was influenced by estrogen receptor levels, histological subtype and histological grade at diagnosis, Ki67 levels at interim biopsy, and NET duration. No differences were found for progression-free survival (PFS) or overall survival (OS) between HER2 groups. The group with Ki67 ≤ 10% at interim biopsy had longer PFS than the Ki67 > 10% group (p < 0.05). No differences for OS were found between these groups. Conclusions: Response to NET was not influenced by low levels of HER2 expression in luminal tumors when compared to HER2-zero tumors. PFS was longer for patients who had lower Ki67 levels at interim biopsy after NET.

Purpose: Marker placement in a pathological node improves extirpation rates in breast cancer cases with limited axillary involvement. Our goal was to assess the current indications for seed-marked axillary lymph node dissection (SMALND). Methods: We conducted a descriptive observational study, including 93 patients with cN1 breast cancer treated between January 2019 and December 2023. Seed placement was performed under ultrasound guidance, days before the procedure. Intraoperative detection was achieved using a probe, and resection was confirmed radiologically. Results: The primary indication was post-neoadjuvant therapy (72 patients: 60 for chemotherapy and 12 for hormone therapy), followed by initial surgery (14) and a single axillary recurrence (8). The extirpation rate of the marked axillary lymph node was 100%. In targeted axillary dissection (TAD), the concordance rate between the sentinel node and the marked axillary node was 85%. In the 12 cases of initial surgery, axillary lymphadenectomy was avoided because the marked node matched the sentinel node and was the only one involved. Conclusions: The use of seeds was proven to be highly useful in axillary surgery, both in cases of negativization following neoadjuvant therapy and in those with low axillary involvement or a single axillary recurrence.

Marker placement in a pathological node improves extirpation rates in breast cancer cases with limited axillary involvement. Our goal was to assess current indications for seed marked axillary lymph node dissection (SMALND). We conducted a descriptive observational study including 93 patients with cN1 breast cancer between January 2019 and December 2023. Seed placement was performed under ultrasound guidance days before the procedure. Intraoperative detection was achieved using a probe, and resection was confirmed radiologically. The primary indication was post neoadjuvant therapy (72 patients: 60 chemotherapy and 12 hormone therapy), followed by initial surgery (13), and single axillary recurrence (8). The extirpation rate of the marked axillary lymph node was 100%. In Target Axillary Dissection (TAD), the concordance rate between sentinel node and marked axillary node was 85%. In the 12 cases of initial surgery, axillary lymphadenectomy was avoided because the marked node matched the sentinel node and was the only one involved. The use of seeds has proven to be highly useful in axillary surgery, both in cases of negativization following neoadjuvant therapy and in those with low axillary involvement or single axillary recurrence.

Background: The SimZones model is an organizational framework for simulation-based education that structures learning across 5 progressive zones, from self-directed preparatory activities (zone 0) to team-based clinical scenarios (zones 1‐4). However, empirical evidence on the impact of zone 0 regarding procedural skill acquisition and retention remains limited. Objective: The present pilot study aimed to build on this evidence gap by examining whether the addition of a structured zone 0 self-directed preparatory phase, delivered through interactive video (IV), could enhance cardiopulmonary resuscitation (CPR) competence acquisition, skill retention, and CPR quality among nursing students when combined with conventional instructor-led zone 1 training, while also assessing the feasibility and acceptability of the intervention. Methods: A total of 52 nursing students from San Pablo CEU University (Madrid, Spain) were randomly assigned to an experimental group (n=33, SimZone 0 IV followed by SimZone 1 instructor-led seminar) or a control group (n=19, SimZone 1 instructor-led seminar only). CPR competence acquisition, skill retention, CPR quality, and feasibility were assessed immediately after zone 1 training and at 3 and 6 months. Results: In the self-directed zone 0 phase, 73% (24/33) of experimental group students achieved competence. After zone 1 training, 100% (28/28) of the experimental group achieved competence vs 84% (16/19) of the control group ( P =.06, Fisher exact test). At 3 months, competence was 96% (23/24) vs 71% (10/14; P =.05), and at 6 months, 96% (22/23) vs 62% (8/13; P =.02). Mean CPR quality scores were consistently higher in the experimental group across all time points (zone 1: 94%, SD 11.8% vs 90%, SD 16.4%; 3 months: 92%, SD 10.9% vs 90%, SD 12.1%; and 6 months: 92%, SD 10.9% vs 85%, SD 17.8%). The intervention was feasible, well accepted, and free of adverse events or technical issues. Conclusions: Self-directed IV learning as a preparatory phase before instructor-led training is feasible, acceptable, and is associated with preliminary signals of enhanced CPR skill acquisition and retention among nursing students. These findings should be interpreted with caution given the pilot nature of the study and the small sample size.

Human epidermal growth factor receptor 2 (HER2)-enriched breast cancers (BC) present the highest rates of pathological response to primary systemic therapy (PST), but they are also the ones that tend to be larger at diagnosis, with microcalcifications and, often, with axillary involvement. If we do not have a reliable method to predict the degree of response, we may not be able to transfer the benefits of PST to surgery. The post-PST surgery planning is guided by the findings in the magnetic resonance imaging (MRI), whose predictive capacity, although high, is far from optimal. Thus, it seems interesting to find other variables to improve it. A retrospective observational study including women with HER2 BC treated with PST and further surgery was conducted. Information regarding clinical, radiological, and histopathological variables was gathered from a total of 132 patients included. Radiological complete response (rCR) was achieved in 65.9% of the sample, and pathological complete response (pCR), according to Miller and Payne criteria, in 58.3% of cases. A higher Ki67 value, the absence of Hormonal Receptors expression, and an rCR was significantly related to a pCR finding. This information impacts directly in surgery planning, as it permits adjustment of the breast resection volume.