Several noteworthy preclinical investigations in the field of theranostics encompass the use of 125I/225At-labelled anti-CXCR4 monoclonal antibody for acute myeloid leukaemia [75], 177Lu-labelled anti-EGFR mAb for breast cancer [76], 111In-NLS-CSL360 for leukaemia [77], 188Re-6D2 for melanoma [78], and 111In-DTPA-CD166tp-G18C for colorectal cancer [79]. The gene discussed is CXCR4; the disease is breast cancer.