(a) Baseline PET/CT images obtained in a Biograph Duo LSO (Siemens) 75min after injection of 405 MBq of 18FLT in a 47-year-old woman with a right-sided infiltrating ductal carcinoma (SUVmax = 5,42) (arrow) and lymph node uptake (SUVmax = 1,85) (arrowhead). Physiological bone marrow uptake was identified. (b) PET/CT images obtained 75min after injection of 529 MBq of 18FLT after one cycle of neoadjuvant therapy. SUVmax decreased to 3,57 in the primary tumour and to 0,80 in the lymph node, consistent with metabolic response. Reprinted under a Creative Commons (CC BY 4.0) license from: Peñuelas I, Domínguez-Prado I, García-Velloso MJ, Martí-Climent JM, Rodríguez-Fraile M, Caicedo C, Sánchez-Martínez M, Richter JA. PET Tracers for Clinical Imaging of Breast Cancer. J Oncol. 2012;2012:710561.