The GRPR, in particular, has attracted much attention in oncology and in nuclear medicine by virtue of its high-density expression in major human cancers, such as prostate [3,4,5], breast [6,7,8,9], and small-cell lung cancer [10], as well as in gastrinoma, gastrointestinal stromal tumors [11,12], and other cancer types [13]. The gene discussed is GRPR; the disease is cancer.