[Cancer of the breast: the return of lymphoscintigraphy?]

Lymphoscintigraphy, after arousing great hope in the past in the field of breast cancer, has now been abandoned. The inability of this examination to predict the metastatic status of the nodes, and progress in therapeutic concepts have led to abandoning this technique. However, certain problems encountered by regional irradiation programmes and the work concerning sentinel node detection may bring this technique back into the spotlight. Lymphoscintigraphy may make it possible to adopt an individual approach, case by case, of the lymphatic drainage basins in breast tumors, thus enabling certain patients to benefit from regional irradiation when it would not have been traditionally recommended for this irradiation. Another aspect concerns the problem of the volumes irradiated. Work carried out with lymphoscintigraphy has enabled internal mammary chain nodes to be precisely located. Theses studies show the necessity of adapting the irradiation field to each individual case, but the clinical impact is limited, in the end, by the low recurrence rate in the internal mammary chain area. However, the new techniques of computer merging of scintigraphic and scanner images could enable the spatial position of the nodes in the upper axillary and supraclavicular regions to be determined. This would have, a priori, much wider clinical impact. Lymphoscintigraphic detection of the sentinel node is another field of major interest, but this technique is in competition with staining techniques. This procedure leads to a large reduction in morbidity of axillary surgery in 70% of patients. The use of techniques for detecting micrometastases in the sentinel node opens prospects in terms of prognosis. The qualities of differents radiotracers and different injection sites possible are also discussed.