Nuclear Medicine Therapy : Current Status and Future Prospects

Radioisotope therapy began in 1942 with the use of /sup 131/I for Graves disease and /sup 32/P for polycythemia vera. Local therapy with radioisotopes includes radiocolloids for malignant pleural and peritoneal effusions, intra-articular radiocolloids for chronic synovitis, intra-arterial radioactive microsphere for liver metastases, and intralymphatic administration for malignancies of the lymphatic system. The most widely practised use of radioisotopes for therapy is for the management of hyperthyroidism by /sup 131/I. Each school has developed its own treatment schedule for controlling the disease without producing too unacceptable an incidence of late hypothyroidism. /sup 131/I is also being used effectively for thyroid cancer, particularly at the Radiation Medicine Centre, BARC. There is hope that a new generation of radiolabelled compounds is round the corner for therapy. As in the case of radiopharmaceuticals for diagnosis, the shift has been from simple inorganic compounds to tailored organic ones. Radiolabelled monoclonal antibodies aimed against specific tumour antigens have already shown great promise. Another area of interest is the use of minute lipid spheroids (vesicles) enclosing the radioactive drug which can be targeted to the tumour