ERBB2 and breast cancer: In nonpregnant patients with breast cancer, radiological staging is indicated in cases with high-risk characteristics such as large tumour size (≥50 mm), involved axillary lymph nodes, aggressive biology [high grade or proliferation index, triple-negative disease, human epidermal growth factor receptor 2 (HER2)-positive disease], or where the clinical picture is suggestive of distant metastatic disease [13,14].