[en] Nuclear medicine has traditionally contributed to molecular oncology by allowing noninvasive monitoring of tumor metabolism, growth and genetic changes, thereby providing a basis for appropriate biology-based treatment planning. However, NM techniques are now being applied as an active therapeutic tool in novel molecular approaches for cancer treatment. Such areas include research on cancer therapy with radiolabeled ligands or oligonucleotides, and utilization of synergism between NM radiotherapy and gene transfer techniques. Here we will focus on novel aspects of nuclear medicine therapy