SARS-CoV-2 Serologic Assays Dependent on Dual-Antigen Binding Demonstrate Diverging Kinetics Relative to Other Antibody Detection Methods.

Longitudinal studies assessing durability of the anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) humoral immune response have generated conflicting results. This has been proposed to be due to differences in patient populations, the lack of standardized methodologies, and the use of assays that measure distinct aspects of the humoral response. SARS-CoV-2 antibodies were serially measured in sera from a cohort of 44 well-characterized convalescent plasma donors over 120 days post-COVID-19 symptom onset, utilizing eight assays, which varied according to antigen source, the detected antibody isotype, and the activity measured (i.e., binding, blocking, or neutralizing). While the majority of assays demonstrated a gradual decline in antibody titers over the course of 120 days, the two electrochemiluminescence immunoassay Roche assays (Roche Diagnostics Elecsys anti-SARS-CoV-2 [qualitative, nucleocapsid based] and Roche Diagnostics Elecsys anti-SARS-CoV-2 S [semiquantitative, spike based]), which utilize dual-antigen binding for antibody detection, demonstrated stable and/or increasing antibody titers over the study period. This study is among the first to assess longitudinal, rather than cross-sectional, SARS-CoV-2 antibody profiles among convalescent COVID-19 patients, primarily using commercially available serologic assays with Food and Drug Administration emergency use authorization. We show that SARS-CoV-2 antibody detection is dependent on the serologic method used, which has implications for future assay utilization and clinical value.

Surgical Management of Axilla Following Neoadjuvant Endocrine Therapy.

BACKGROUND: Randomized clinical trials support deescalation of axillary surgery in breast cancer patients with low-volume axillary disease treated with a surgery-first approach. However, few data exist to guide axillary surgery following neoadjuvant endocrine therapy (NET). Therefore, we evaluated the extent and outcomes of axillary surgery in a contemporary cohort of NET patients, a treatment approach that has become particularly relevant during the coronavirus disease-19 (COVID-19) pandemic. PATIENTS AND METHODS: We identified invasive breast cancer patients treated with NET between October 2008 and November 2019. Patients presenting with stage IV disease or recurrent disease were excluded. Statistical analyses were performed using chi-square, Fisher's exact, and Wilcoxon rank-sum tests. RESULTS: 194 invasive breast cancers in 186 patients (median age 66 years) were evaluated; 81 patients had breast-conserving surgery (BCS), while 113 underwent mastectomy. Eighty-four patients (43.3%) were biopsy-proven cN+ with 4/84 (4.8%) ypN0 following NET. Among cN+ patients, 14 (16.7%) had sentinel lymph node biopsy (SLNB) only, 27 (32.1%) had SLNB + axillary lymph node dissection (ALND), and 43 (51.2%) had ALND. Among 110 cN0 patients, 99 had axillary surgery with 28/99 (28.3%) ypN+: SLNB in 83 (75.5%), SLNB+ALND in 14 (12.7%), and ALND in 2 (1.8%). Among all ypN+ patients, 23/108 (21.3%) had SLNB alone: 18/43 (41.9%) of BCS and 5/65 (7.7%) mastectomy patients (p < 0.001). After median follow-up of 35 months, no regional recurrences were observed. CONCLUSIONS: Among biopsy-proven cN+ NET patients, we observed deescalation of axillary surgery in selected patients, despite a low nodal pathologic complete response (pCR) rate, without nodal recurrences. These data suggest that patients with low-volume axillary disease treated with NET may be managed similarly to patients treated with a surgery-first approach.

Convalescent Plasma for Infectious Diseases: Historical Framework and Use in COVID-19.

Convalescent plasma has emerged as a promising therapeutic agent for patients with coronavirus disease 2019 (COVID-19), has received emergency use authorization, and is being widely used during the COVID-19 pandemic. Passive antibody therapy via plasma or serum has been successfully used to treat infectious diseases for more than a century. Passive antibody administration is based on the presumption that convalescent plasma or serum contains therapeutic antibodies that can be passively transferred to the plasma recipient. There are numerous examples in which convalescent plasma has been used successfully as post-exposure prophylaxis and treatment of infectious diseases, including previous coronavirus outbreaks. In the context of the COVID-19 pandemic, convalescent plasma was demonstrated to be safe and potentially effective among patients infected with COVID-19. This review provides an overview of the historical uses of convalescent plasma therapy, summarizes current evidence for convalescent plasma use for COVID-19, and highlights future antibody therapies.

Immediate Breast Reconstruction Outcomes in Patients with Prior Mantle and Whole Breast Irradiation.

Background: Limited studies have detailed the risk of mastectomy with immediate breast reconstruction among women who previously received mantle field radiation. Methods: A single institution retrospective review from 2010 to 2020 of patients previously treated with mantle field radiation (MF-RT) and subsequent mastectomy with immediate breast reconstruction was performed. Patients with prior whole breast irradiation (WBI) were also included as a reference group. Demographic, comorbidity, and surgical factors were collected. The primary outcome was major complications, defined as those requiring reoperation, intravenous antibiotics, or debridement. Results: Fourteen patients with prior MF-RT (27 breasts) and 129 with prior WBI (132 breasts) underwent mastectomy with immediate reconstruction. Prior MF-RT patients were significantly younger (43.8 versus 57.5, P < 0.001) and had significantly lower body mass index (23.6 versus 26.8, P = 0.004) compared with prior WBI patients. Nipple-sparing mastectomy was significantly more common in the mantle than in the WBI patients (78.6% versus 35.9%, P = 0.03). Most (13, 92.9%) prior mantle patients underwent tissue expander/implant-based reconstruction. Three (21.4%) prior MF-RT patients had major complications at any point, but none required an alternative type of reconstruction. On multiple variable analysis, there was no significant difference in major complication risk among prior MF-RT versus WBI patients (HR 0.74, confidence interval 0.20-2.70, P = 0.74). Conclusion: Immediate tissue expander/implant-based reconstruction in prior MF-RT patients seems safe, with a complication risk similar to that of prior WBI patients.