New horizons for therapeutic nuclear medicine in 1981.

The therapeutic approach of internally administered radiopharmaceuticals offers the potential to outmode the present approaches of conventional radiation therapy and chemotherapy because of three characteristics: 1. The therapeutic use of radiopharmaceuticals may deliver as much as orders of magnitude larger rad doses than conventional radiation therapy to target tissues, selectively irradiating these tissues internally in one radiation dose. 2. The therapeutic use of radiopharmaceuticals is followed by a lower incidence of leukemia and other cancers. 3. The treatment is comparatively noninvasive and nontraumatic. We can now make this rather strong statement with fairly firm conviction because Na131I has been used since 1946 (33 years) to treat almost a million patients for hyperthyroidism (a) and in approximately 5000 patients for well-differentiated thyroid cancer (b); NaH2PO4(P-32) has been used for 35 years to treat approximately 25,000 patients with polycythemia vera (3-5).