COVID-19 Vaccine-Related Axillary Adenopathy on Breast Imaging: Follow-Up Recommendations and Histopathologic Findings

Vaccination of Adults With Cancer: ASCO Guideline

PURPOSE

To guide the vaccination of adults with solid tumors or hematologic malignancies.

METHODS

A systematic literature review identified systematic reviews, randomized controlled trials (RCTs), and nonrandomized studies on the efficacy and safety of vaccines used by adults with cancer or their household contacts. This review builds on a 2013 guideline by the Infectious Disease Society of America. PubMed and the Cochrane Library were searched from January 1, 2013, to February 16, 2023. ASCO convened an Expert Panel to review the evidence and formulate recommendations.

RESULTS

A total of 102 publications were included in the systematic review: 24 systematic reviews, 14 RCTs, and 64 nonrandomized studies. The largest body of evidence addressed COVID-19 vaccines.

RECOMMENDATIONS

The goal of vaccination is to limit the severity of infection and prevent infection where feasible. Optimizing vaccination status should be considered a key element in the care of patients with cancer. This approach includes the documentation of vaccination status at the time of the first patient visit; timely provision of recommended vaccines; and appropriate revaccination after hematopoietic stem-cell transplantation, chimeric antigen receptor T-cell therapy, or B-cell-depleting therapy. Active interaction and coordination among healthcare providers, including primary care practitioners, pharmacists, and nursing team members, are needed. Vaccination of household contacts will enhance protection for patients with cancer. Some vaccination and revaccination plans for patients with cancer may be affected by the underlying immune status and the anticancer therapy received. As a result, vaccine strategies may differ from the vaccine recommendations for the general healthy adult population vaccine.Additional information is available at www.asco.org/supportive-care-guidelines.

Comparison of Axillary Lymph Nodes on Breast MRI Before and After COVID-19 Booster Vaccination

RATIONALE AND OBJECTIVES

Vaccine-related lymphadenopathy is a frequent finding following initial coronavirus disease 2019 (COVID-19) vaccination, but the frequency after COVID-19 booster vaccination is still unknown. In this study we compare axillary lymph node morphology on breast MRI before and after COVID-19 booster vaccination.

MATERIALS AND METHODS

This retrospective, single-center, IRB-approved study included patients who underwent breast MRI between October 2021 and December 2021 after the COVID-19 booster vaccination. The axillary lymph node with the greatest cortical thickness ipsilateral to the side of vaccination was measured on MRI after booster vaccination and before initial COVID-19 vaccination. Comparisons were made between patients with and without increase in cortical thickness of ≥ 0.2 cm. Continuous covariates were compared using Wilcoxon rank-sum test and categorical covariates were compared using Fisher's exact test. Multiple comparison adjustment was made using the Benjamini-Hochberg procedure.

RESULTS

All 128 patients were included. Twenty-four of 128 (19%) displayed an increase in lymph node cortical thickness of ≥ 0.2 cm. Patients who received the booster more recently were more likely to present cortical thickening, with a median of 9 days (IQR 5, 20) vs. 36 days (IQR 18, 59) (p < 0.001). Age (p = 0.5) and type of vaccine (p = 0.7) were not associated with thickening. No ipsilateral breast cancer or malignant lymphadenopathy were diagnosed on follow-up.

CONCLUSION

Axillary lymphadenopathy on breast MRI following COVID-19 booster vaccination is a frequent finding, especially in the first 3 weeks after vaccination. Additional evaluation or follow-up may be omitted in patients with low concern for malignancy.

Axillary lymph nodes enlargement after Sars-CoV-2 vaccine in patients undergoing breast examination: a single-centre experience in 285 women

PURPOSE

To assess the incidence of axillary lymphadenopathy over established time ranges after COVID-19 vaccination and lymph node pathologic features (i.e. size increase and qualitative characteristics) in subjects undergoing axillary evaluation during a breast imaging examination.

METHODS AND MATERIALS

The institutional review board approved this prospective study.

INCLUSION CRITERIA

women undergoing mammography and breast ultrasound between July and October 2021; information about the COVID-19 vaccine and infection, if any.

EXCLUSION CRITERIA

known metastatic lymphadenopathy. Participants were divided into 5 subgroups according to time between vaccine and imaging: < 6 weeks; 7-8 weeks; 9-10 weeks; 11-12 weeks; > 12 weeks. Evaluation of axillary lymph nodes was performed with ultrasound. Descriptive statistical analysis was performed. p < 0.05 was considered significant.

RESULTS

A total of 285 women were included. Most of the patients underwent Moderna vaccine (n = 175, 61.4%). 63/285 patients had a previous history of breast cancer (22.1%). 13/17 (76.5%) patients with previous COVID-19 infection had no previous history of cancer, whereas 4/17 had a previous history of cancer (p < .001). 41/285 (14.4%) women showed lymphadenopathy, and they were significantly younger (46.9 ± 11.6 years) than women with borderline (54.0 ± 11.9 years) or no lymphadenopathy (57.3 ± 11.9 years) (p < .001). Lymphadenopathy and borderline lymphadenopathy were more frequently observed in the Moderna-vaccinated women and in the subgroup of patients evaluated < 6 weeks after vaccination (p < 0.001). The most common pathologic feature was cortical thickening, followed by complete or partial effacement of fatty hilum.

CONCLUSION

A lymphadenopathy within 12 weeks after vaccination is a common finding particularly in younger women and after Moderna vaccine and no further assessment should be required.

Axillary Lymph Nodes in Breast Cancer Patients After COVID-19 Vaccine

One of the side effects of vaccines used to end the COVID-19 epidemic is non-specifically enlarged axillary lymph nodes. Such lymphadenopathy detected during clinical examination of breast cancer patients may require additional imaging or interventional procedures that should not normally be performed. This study has been designed to estimate the incidence of palpable enlarged axillary lymph node in breast cancer patients who had received COVID-19 vaccination in the past 3 months in the same arm as compared to those without vaccination. Breast cancer patients admitted to M.U. Medical Faculty Breast polyclinic between January 2021 and March 2022 were screened, and clinical staging was performed after thorough clinical examination. Among these patients with suspected enlarged axillary lymph node and those undergoing sentinel lymph node biopsy (SLNB), they were divided into two groups as vaccinated and unvaccinated. Age, menopausal status, tumor size, tumor location, surgery, pathology results, hormonal receptor status, and SLNB results were statistically compared with groups. There was no significant difference between groups in terms of age, menopause, tumor size, tumor location, surgery, pathological results, and hormone receptor status. The SLNB being reported as reactive only was 89.1% in the vaccinated group and 73.2% in the non-vaccinated group which was statistically significant different. Reactive lymph nodes were commonly found with an excess of 16% in patients who had received COVID-19 vaccination in the past 3 months. This required caution and additional examination of the axillary lymph nodes in this period.

Imaging of COVID-19 Vaccine-Related Axillary Lymphadenopathy: Initial Outcomes Based on US Features of Axillary Lymph Nodes

OBJECTIVE

The purpose of this study is to describe the imaging characteristics and outcomes of COVID-19 vaccine-related axillary adenopathy and subsequent follow-up.

METHODS

This was an IRB-approved, retrospective study of patients with imaging evidence of axillary lymphadenopathy who had received at least one dose of a COVID-19 vaccine and presented between January 1, 2021, and February 28, 2021. Sonographic cortical thickness and morphology was evaluated. A mixed effects model was used to model lymph node cortical thickness decrease over time.

RESULTS

A total of 57 women were identified with lymphadenopathy and a COVID vaccination during the study period with 51 (89.5%) women completing imaging surveillance or undergoing tissue sampling of a lymph node. Three women (5.9%) were diagnosed with metastatic breast cancer to an axillary node. There was a statistically significant correlation with cortical thickness at initial US evaluation and malignancy (7.7 mm [SD ± 0.6 mm] for metastatic nodes and 5 mm [SD ± 2 mm] for benign nodes, P = 0.02). Suspicious morphological features (effacement of fatty hilum, P = 0.02) also correlated with malignancy. Time to resolution of lymphadenopathy can be prolonged with estimated half-life of the rate of decrease in cortical thickness modeled at 77 days (95% CI, 59-112 days). Diffuse, smooth cortical thickening over 3 mm was the most common lymph node morphology.

CONCLUSION

Malignant lymph node morphology and cortical thickness best predicted malignancy. Benign hyperplastic lymph nodes were the most common morphology observed after COVID-19 vaccination. Lymphadenopathy after vaccination is slow to resolve.

Axillary Lymphadenopathy Associated With COVID-19 Vaccination: Updates and Recommendations

Lymphadenopathy (LAD) associated with vaccination has been documented as complicating the evaluation of metastatic malignancy. In the past this was a limited finding, primarily documented in association with smallpox and H1N1 vaccination.The advent of the novel mRNA vaccine for COVID-19 in December of 2021, and subsequent large scale vaccination effort, has resulted in a marked increase in the identification of LAD associated with vaccination. Because axillary LAD is a concerning sign of metastatic disease in breast cancer, identifying the difference between benign inflammatory reaction and concerning LAD and avoiding unnecessary additional imaging and biopsy is an essential skill. This article describes the current literature, recommendations for follow-up, and interventions to improve diagnostics.

Axillary Lymphadenopathy in the COVID-19 Era: What the Radiologist Needs to Know

Axillary lymphadenopathy caused by the high immunogenicity of messenger RNA (mRNA) COVID-19 vaccines presents radiologists with new diagnostic dilemmas in differentiating vaccine-related benign reactive lymphadenopathy from that due to malignant causes. Understanding axillary anatomy and lymphatic drainage is key to radiologic evaluation of the axilla. US plays a critical role in evaluation and classification of axillary lymph nodes on the basis of their cortical and hilar morphology, which allows prediction of metastatic disease. Guidelines for evaluation and management of axillary lymphadenopathy continue to evolve as radiologists gain more experience with axillary lymphadenopathy related to COVID-19 vaccines. General guidelines recommend documenting vaccination dates and laterality and administering all vaccine doses contralateral to the site of primary malignancy whenever applicable. Guidelines also recommend against postponing imaging for urgent clinical indications or for treatment planning in patients with newly diagnosed breast cancer. Although conservative management approaches to axillary lymphadenopathy initially recommended universal short-interval imaging follow-up, updates to those approaches as well as risk-stratified approaches recommend interpreting lymphadenopathy in the context of both vaccination timing and the patient’s overall risk of metastatic disease. Patients with active breast cancer in the pretreatment or peritreatment phase should be evaluated with standard imaging protocols regardless of vaccination status. Tissue sampling and multidisciplinary discussion remain useful in management of complex cases, including increasing lymphadenopathy at follow-up imaging, MRI evaluation of extent of disease, response to neoadjuvant treatment, and potentially confounding cases.

An invited commentary by Weinstein is available online.

^©RSNA, 2022

COVID-19 Vaccine-Associated Lymphadenopathy in Breast Imaging Recipients: A Review of Literature

The unpredictability of the coronavirus disease 2019 (COVID-19) pandemic has created an ongoing global healthcare crisis. Implementation of a mass vaccination program to accelerate disease control remains in progress. Although injection site soreness, fatigue, and fever are the most common adverse reactions reported after a COVID-19 vaccination, ipsilateral lymph node enlargement has increasingly been observed. In patients undergoing routine screening and surveillance for breast cancer, interpreting lymphadenopathy (LAP) is challenging in the setting of a recent COVID-19 vaccination. With a growing proportion of the population receiving the vaccine, a multifaceted approach is necessary to avoid unnecessary and costly workup. In this comprehensive review, we summarize the existing literature on COVID-19 vaccine-associated LAP in breast imaging patients.