[Breast carcinoma. Technical problems of radiotherapy. Proposal of an algorithm as an alternative to the lack of scintigraphic visualization of the internal mammary lymph nodes].

In early breast cancer, radiation therapy following conservative surgery needs a topographic evaluation of internal mammary lymph nodes. Three-dimensional lymphoscintigraphy (IML3D) is an useful method for this purpose. The average depth of the lymph nodes is closely correlated with the square root of the body weight/height ratio. We calculated the individual maximum depth of the lymph nodes from this function; the parameter was then verified with the experimental data from our series of cases (53 patients). Although the suggested algorithm needs to be verified on a larger number of patients, we believe the empirical maximum depth measurement to be useful when IML3D is unfeasible or the internal mammary lymph nodes are not demonstrated on scintigraphic scans.