Extracellular Vesicle DNA Extraction and Sequencing in Ancient Serum Samples From Patients With Breast Cancer.

BACKGROUND/AIM: Extracellular vesicle DNA (EV-DNA) has emerged as a novel biomarker for tumor mutation detection using liquid biopsies, exhibiting biological advantages compared to cell-free DNA (cfDNA). This study assessed the feasibility of EV-DNA and cfDNA extraction and sequencing in old serum samples of patients with breast cancer (BC). PATIENTS AND METHODS: A total of 28 serum samples of 27 patients with corresponding clinical information were collected between 1983 and 1991. EV-DNA was extracted using Exo-GAG kit (Nasabiotech) and cfDNA using QIAsymphony DSP Virus/Pathogen Midi Kit (Qiagen), respectively. Subsequently, 10 matched samples (EV-DNA n=5, cfDNA n=5) of five patients were subjected to sequencing using the Oncomine™ Breast cfDNA Research Assay v2 (Thermo Fisher Scientific). RESULTS: Samples were collected on median 1.9 years after primary diagnosis [interquartile range (IQR)=0.2-7.2]. Median follow-up was 9.5 years (IQR=5.2-14.2). Median age of serum samples was 36.1 years (IQR=34.5-37.3). EV-DNA and cfDNA were extracted from 100% (28/28) of the included samples. Both, DNA quantity and concentration were comparable between EV-DNA and cfDNA. Sequencing was successfully performed in 100% (10/10) of the included samples. Two matched analyses yielded equivalent results in EV-DNA and cfDNA (no mutations, n=1; PIK3CA mutation, n=1), whilst in two analyses, PIK3CA mutation was only found in cfDNA, and in one analysis, a TP53 mutation was only found in EV-DNA. CONCLUSION: EV-DNA extraction and sequencing in old serum samples of patients with BC is feasible and has the potential to address clinically relevant questions in longitudinal studies.

Association of relative resection volume with patient-reported outcomes applying different levels of oncoplastic breast conserving surgery - A retrospective cohort study.

INTRODUCTION: The American Society of Breast Surgeons (ASBrS) recently classified oncoplastic breast conserving surgery (OBCS) into two levels. The association of resection ratio during OBCS with patient-reported outcomes (PRO) is unclear. MATERIALS AND METHODS: Patients with stage 0-III breast cancer undergoing OBCS between 01/2011-04/2023 at a Swiss university hospital, who completed at least one postoperative BREAST-Q PRO questionnaire were identified from a prospectively maintained institutional database. Outcomes included differences in PROs between patients after ASBrS level I (<20 % of breast tissue removed) versus level II surgery (20-50 %). RESULTS: Of 202 eligible patients, 129 (63.9 %) underwent level I OBCS, and 73 (36.1 %) level II. Six patients (3.0 %) who underwent completion mastectomy were excluded. The median time to final PROs was 25.4 months. Patients undergoing ASBrS level II surgery were more frequently affected by delayed wound healing (p < 0.001). ASBrS level was not found to independently predict any BreastQ domain. However, delayed wound healing was shown to reduce short-term physical well-being (estimated difference -26.27, 95 % confidence interval [CI] -39.33 to -13.22, p < 0.001). Higher age was associated with improved PROs. CONCLUSION: ASBrS level II surgery allows the removal of larger tumors without impairing PROs. Preventive measures for delayed wound healing and close postoperative follow-up to promptly treat wound healing disorders may avoid short-term reductions in physical well-being.

Use of sentinel lymph node biopsy in elderly patients with breast cancer - 10-year experience from a Swiss university hospital.

BACKGROUND: The Choosing Wisely initiative recommended the omission of routine sentinel lymph node biopsy (SLNB) in patients ≥ 70 years of age, with clinically node-negative, early stage, hormone receptor (HR) positive and human epidermal growth factor receptor 2 (Her2) negative breast cancer in August 2016. Here, we assess the adherence to this recommendation in a Swiss university hospital. METHODS: We conducted a retrospective single center cohort study from a prospectively maintained database. Patients ≥ 18 years of age with node-negative breast cancer were treated between 05/2011 and 03/2022. The primary outcome was the percentage of patients in the Choosing Wisely target group who underwent SLNB before and after the initiative went live. Statistical significance was tested using chi-squared test for categorical and Wilcoxon rank-sum tests for continuous variables. RESULTS: In total, 586 patients met the inclusion criteria with a median follow-up of 2.7 years. Of these, 163 were ≥ 70 years of age and 79 were eligible for treatment according to the Choosing Wisely recommendations. There was a trend toward a higher rate of SLNB (92.7% vs. 75.0%, p = 0.07) after the Choosing Wisely recommendations were published. In patients ≥ 70 years with invasive disease, fewer received adjuvant radiotherapy after omission of SLNB (6.2% vs. 64.0%, p < 0.001), without differences concerning adjuvant systemic therapy. Both short-term and long-term complication rates after SLNB were low, without differences between elderly patients and those < 70 years. CONCLUSIONS: Choosing Wisely recommendations did not result in a decreased use of SLNB in the elderly at a Swiss university hospital.

Uncertainties and controversies in axillary management of patients with breast cancer.

The aims of this Oncoplastic Breast Consortium and European Breast Cancer Research Association of Surgical Trialists initiative were to identify uncertainties and controversies in axillary management of early breast cancer and to recommend appropriate strategies to address them. By use of Delphi methods, 15 questions were prioritized by more than 250 breast surgeons, patient advocates and radiation oncologists from 60 countries. Subsequently, a global virtual consensus panel considered available data, ongoing studies and resource utilization. It agreed that research should no longer be prioritized for standardization of axillary imaging, de-escalation of axillary surgery in node-positive cancer and risk evaluation of modern surgery and radiotherapy. Instead, expert consensus recommendations for clinical practice should be based on current evidence and updated once results from ongoing studies become available. Research on de-escalation of radiotherapy and identification of the most relevant endpoints in axillary management should encompass a meta-analysis to identify knowledge gaps, followed by a Delphi process to prioritize and a consensus conference to refine recommendations for specific trial designs. Finally, treatment of residual nodal disease after surgery was recommended to be assessed in a prospective register.