SLC7A5 and cancer: As an example, LAT1 substrates are used in PET (Positron Emission Tomography) that is a diagnostic technique based on the use of radiolabelled molecules, such as tyrosine, phenylalanine and methionine derivatives, which are delivered specifically to cancer cells via LAT1, allowing for identification of metastasis or tumours already at the early stages of the disease [51].