Axillary lymph node imaging in mRNA, vector-based, and mix-and-match COVID-19 vaccine recipients: ultrasound features.

OBJECTIVES: To assess ultrasound characteristics of ipsilateral axillary lymph nodes after two doses of four different COVID-19 vaccination protocols, to determine whether these parameters differed with age, and to describe how they changed on follow-up imaging. METHODS: A total of 247 volunteer employees from our center who had received two doses of COVID-19 vaccination were recruited and followed prospectively. Axillary ultrasound of the ipsilateral vaccinated arm was performed the week after receiving the second dose to analyze lymph node features (number, long-axis, cortical thickness, morphology, and vascular imaging). Axillary lymphadenopathy resulting from four vaccination protocols-mRNA (BNT162b2, mRNA-1273), ChAdOx1-S, and mix-and-match-was compared. Analysis was conducted using the Kruskal-Wallis test and post hoc analysis with Bonferroni corrections. Nodal reactogenicity was evaluated for two age groups: young (< 45 years old) and middle-aged ( ≥ 45 years old). All parameters were compared between both groups using an unpaired-sample Student t test. A p value < 0.05 was considered statistically significant. RESULTS: Significantly higher values for total number of visible nodes, cortical thickness, Bedi's classification (p < 0.001), and vascularity (p < 0.05) were observed in mRNA vaccine recipients compared to full ChAdOx1-S protocol recipients. Moreover, mix-and-match protocol recipients showed greater nodal cortical thickness and higher Bedi's classification than full ChAdOx1-S recipients (p < 0.001). Analyses between age groups revealed greater cortical thickness, Bedi's classification, and color Doppler signal in younger patients (p < 0.05). CONCLUSIONS: Nodal parameters of Bedi's classification and cortical thickness were more often increased in mRNA and mix-and-match vaccine recipients when compared to ChAdOx1-S vaccine alone, especially in younger patients. KEY POINTS: • Hyperplastic lymphadenopathy was observed more frequently in mRNA and mix-and-match vaccine protocols compared to full vector-based vaccination. • Higher values for cortical thickness, Bedi's classification, and color Doppler signal parameters were identified in younger patients. • Observed lymph node findings normalized in greater than 80% of patients by the third month following vaccination.

Leveraging the increased rates of pathologic complete response after neoadjuvant treatment in breast cancer to de-escalate surgical treatments.

INTRODUCTION: Breast conservative surgery (BCS) and sentinel lymph node biopsy (SLNB) after neoadjuvant treatment (NAT) is safe and effective for selected patients. This aim of this study is to evaluate the impact of anatomic site of response on outcomes and to assess the real population who may benefit from nonsurgical approaches after NAT. MATERIAL AND METHODS: From a prospectively maintained database, patients with T1-4 N0-2 breast cancer undergoing NAT were identified. Clinicopathological and survival rates were compared in relation to response and anatomic site of response. RESULTS: Six hundred and forty-six patients were included in the study. Pathologic complete response (pCR) was an independent factor for BCS and SLN. HER2 positive and TN tumors with cN0 achieving a breast pCR remain ypN0 (p = .002). Residual axillary disease was associated with breast residual tumor (p = .05) and subtype (p = .001). With a median follow up of 35.25 months, patients with any pCR had improved survival when compared with partial response, but not significant differences between pCR, axillary pCR, or breast pCR. CONCLUSION: Achieving a pCR increases BCS and SLN. In selected subgroups, sparing any axillary surgery after NAT maybe feasible. In cN+ patients, any pCR was associated with survival, but not the anatomic site of response.

Intraoperative ultrasound margin evaluation as a tool to reduce positive superficial margins in nipple and skin sparing mastectomy in breast cancer patients.

BACKGROUND: Intraoperative ultrasound (IOUS) guided conservative surgery has been shown to reduce rates of positive margins in breast cancer. The aim of the study is to evaluate the feasibility of using IOUS to assess superficial/anterior margins in nipple and skin sparing mastectomy (NSM/SSM) and its impact on reducing rates of positive margins. METHODS: This prospective study includes all breast cancer patients who had an indication for NSM/SSM at our Institution. Superficial margin width was measured by IOUS before surgery and the area marked on the skin. Same measurement was performed afterwards in the mastectomy specimen. Any superficial margin < 5 mm was re-excised intraoperatively following the mark on the skin. RESULTS: Fifty-nine patients were included, 47 patients (79.7%) underwent NSM, and 12 patients (20.3%) a SSM. Of the 59 patients, 23 (38.98%) had margins ≥5 mm and 36 patients (61.02%) had margins of ≤5 mm. Of the 36 patients with superficial margins ≤5 mm, 20 had margins <2 mm, and 6 of them had intraoperative involved superficial margins in final pathology. However, after IOUS-guided re-excision, final pathology showed no involved margins. A 2 mm margin was set as the cut-off point for performing an intraoperative re-excision. IOUS guided re-excisions for intraoperative margins ≤2 mm significantly reduced the risk of close/positive margins in final pathology, p < 0.0001. CONCLUSION: The results showed that IOUS margin evaluation significantly reduced the rate of superficial positive margins in NSM/SSM. It is feasible and effective and may avoid challenging reoperations and/or additional radiation therapy for positive margins.

Neoadjuvant approach in patients with early breast cancer: patient assessment, staging, and planning.

Neoadjuvant treatment (NAT) has become an option in early stage (stage I-II) breast cancer (EBC). New advances in systemic and targeted therapies have increased rates of pathologic complete response increasing the number of patients undergoing NAT. Clear benefits of NAT are downstaging the tumor and the axillary nodes to de-escalate surgery and to evaluate response to treatment. Selection of patients for NAT in EBC rely in several factors that are related to patient characteristics (i.e, age and comorbidities), to tumor histology, to stage at diagnosis and to the potential changes in surgical or adjuvant treatments when NAT is administered. Imaging and histologic confirmation is performed to assess extent of disease y to confirm diagnosis. Besides mammogram and ultrasound, functional breast imaging MRI has been incorporated to better predict treatment response and residual disease. Contrast enhanced mammogram (CEM), shear wave elastography (SWE), or Dynamic Optical Breast Imaging (DOBI) are emerging techniques under investigation for assessment of response to neoadjuvant therapy as well as for predicting response. Surgical plan should be delineated after NAT taking into account baseline characteristics, tumor response and patient desire. In the COVID era, we have witnessed also the increasing use of NAT in patients who may be directed to surgery, unable to have it performed as surgery has been reserved for emergency cases only.

Four-fraction ultra-accelerated minimal breast irradiation in early breast cancer: The initial feasibility results of an institutional experience.

PURPOSE: To evaluate the feasibility, early toxicity, and clinical outcomes of early-breast cancer patients in a single-arm, phase I/II study of an ultra-accelerated, four-fraction schedule of minimal breast irradiation (4f-AMBI) using a multicatheter, minimally-invasive, intraoperative tumor bed implant (MITBI) during breast-conserving surgery (BCS). METHODS AND MATERIALS: Eligible women aged >40 years with clinically and radiologically confirmed, unifocal invasive or in situ ≤3 cm tumors were considered as potential candidates for MITBI during BCS. After the pathology report, patients who met APBI criteria received ultra-accelerated four-fractions irradiation (6.2 Gy BID x 4fx over 2 days) with perioperative HDR-brachytherapy (PHDRBT). Early complications, toxicity, clinical outcomes, and cosmetic results were analyzed. RESULTS: Of 89 patients initially implanted, 60(67.4%) were definitively included in the 4f-AMBI-protocol. The median age was 64.4 years; the median CTV was 32.1 cc (6.9-75.4 cc), and the external-V100 was 43.1 cc (12.87-107 cc), representing 5% of the breast tissue irradiated with a median CTV D90 of 6.2 Gy (5.6-6.28 Gy). The entire local treatment (BCS&MITBI-4f-AMBI) was completed at a median of 8 days (4-10 days). The rate of early complications was 11%. There were no major complications. Acute skin-subcutaneous G1 toxicity was reported in 11.7%, and late G1 toxicity on 36.7%. After a median follow-up of 27 months (11-51 months), the local, elsewhere, locoregional and distant-control rates were 100%, 98.3%, 100%, and 100% respectively. The early-cosmetic evaluation was excellent-good in 94.5% of patients evaluated. CONCLUSIONS: Ultra-accelerated, four-fraction, minimal breast irradiation (4f-AMBI) using a minimally-invasive tumor bed implant procedure is safe, dosimetrically feasible, and shows small irradiated volumes. This program provides low toxicity rates and excellent short-term clinical and cosmesis outcomes.