Fig. 6.

(Case 5): A 71-year-old woman, with a history of a right-sided breast cancer 9 years ago, attended the symptomatic breast clinic with a new lump in her left breast. Mammogram and breast ultrasound identified a 29 mm malignant appearing lesion in the lower inner quadrant of the left breast. Ultrasound of the left axilla was normal. A core biopsy of the left breast mass showed grade 2 invasive ductal cancer, which was ER positive, and HER2 positive. Breast MRI confirmed the presence of a 31 mm spiculated mass in the left breast. Staging CT scans of chest, abdomen and pelvis showed no evidence of metastatic disease, with only small volume para-aortic lymphadenopathy seen, and no pathological lymphadenopathy in the axilla or SCF/ICF bilaterally (left). The patient was started on neoadjuvant chemotherapy to downsize the cancer and facilitate breast conserving surgery. A repeat CT scan was performed after 3 months of neoadjuvant systemic treatment, which identified the interval emergence of prominent right-sided axillary nodes, of uncertain clinical significance (right). The patient had the first dose of the AstraZeneca COVID-19 vaccine administered into the right arm 4 weeks prior. On imaging review, the left breast cancer showed signs of interval response to treatment compared to the previous CT scan. In view of this, and due to the patient's vaccine history, it was felt that the right axillary adenopathy was unlikely to represent metastatic disease, and a 6-month follow-up with an ultrasound of the right axilla was advised. The patient completed neoadjuvant chemotherapy and underwent left breast-conserving surgery and sentinel node biopsy that showed complete pathological response in the breast and no evidence of lymph node metastasis or fibrosis.