Tumor imaging probes for human epidermal growth factor receptor 2 (HER2) [12]–[14], epidermal growth factor receptor (EGFR) [15]–[18], and vascular endothelial growth factor (VEGF) [19], [20], which are the target molecules of trastuzumab, cetuximab/panitumumab, and bevacizumab, respectively, have been developed. The gene discussed is ERBB2; the disease is neoplasm.