Diagnostic accuracy and clinical utility of axillary ultrasound in the evaluation of axillary lymph node status in early breast cancer patients - Schäfgen, B; Riedel, F; Sinn, P; Feisst, M; Hennigs, A; Hug, S; Binning, A; Sohn, C; Golatta, M; Gläser, A; Heil, J (Geburtshilfe und Frauenheilkunde, 2020)