[Therapeutic advances of nuclear medicine in oncology]

With the development of new radiopharmaceuticals there is a tendency to apply nuclear medicine therapy for malignancies of higher incidence (lymphoma, prostate) than the ones which have been treated for many years (thyroid cancer, neuroendocrine tumours). One of the most important areas of current development in radionuclide cancer therapy is the monotherapeutic use of new or already available radiopharmaceuticals in preclinical or phase I studies and to a lesser degree in phase II trials. In this context, the radioimmunotherapy is showing important advances in the treatment of medullary thyroid carcinoma, malignant lymphomas en brain tumours with potential extension to neuroblastoma therapy. The development of DOTA as a chelating agent has lead to the use of Y-90-DOTATOC in the treatment of neuroendocrine tumours, particularly carcinoid tumours, and non-I131I-avid thyroid carcinomas. In an effort to improve tumour targeting together with simultaneous reduction of physiological organ uptake, 131I-MIBG is being used in combination with interferon a and pre-targeting with unlabelled MIBG in the treatment of carcinoid tumours. New routes of administration of radiopharmaceuticals (intratumoral, intra-arterial) have enhanced the treatment of malignancies of liver, pancreas and brain as well as the potential use of radioimmunotherapy by intravesical administration for bladder carcinoma. Another significant tendency in radionuclide therapy is its evolution from monotherapy towards a combined application with other anticancer modalities. Some recent examples of combined therapy with demonstrated anti-tumour effect are found in neuroblastoma (131I-MIBG and chemotherapy), bone metastases of prostatic carcinoma (addition of 89Sr to chemotherapy schedules), brain malignancies (adjuvant use of radioimmnunotherapy in relation to surgery and external radiotherapy) and lymphoma (radioimmunotherapy combined with chemotherapy or immunotherapy). Reinforcing this trend in phase II and III studies as well as the planning of multicenter trials following the guidelines and criteria of clinical oncology will determine the future advances in this field.