FOLH1 and thyroid gland carcinoma: I-131 for thyroid cancer diagnosis and treatment can be considered “old era” theranostics.1Ga-68 prostate-specific membrane antigen (PSMA) and Lu-177 PSMA can be considered “new era” theranostic.2The new era of theranostics has revolutionized nuclear medicine through the prospective phase 3 clinical trials, which have resulted in its adoption into the treatment paradigms of patients, particularly those with neuroendocrine tumors and prostate cancer.