A recent clinical trial performed a first-in-man comparative evaluation of the promising imaging probe [18F] tetrafluoroborate ([18F]BF4− or [18F]TFB) for PET imaging [123] and [99mTc]pertechnetate ([99mTc]TcO4−) for SPECT imaging of hNIS expression in myeloma patients treated with Measles virus-NIS (MV-NIS) and endometrial cancer patients treated with vesicular stomatitis virus co-expressing interferon and hNIS (VSV-hINF-NIS) (NCT03456908) (Figure 2B). The gene discussed is SLC5A5; the disease is endometrial cancer.