Análisis de los riesgos asociados al uso de la técnica VMAT frente a 3DCRT en tratamientos de mama con cadenas ganglionares axilo-claviculares

The use of Volumetric Intensity Modulated ArcTherapy (VMAT) for breast cancer treatments has always been controversial. The tighter conformation of the high absorbed doses around the target that VMAT provides over conformed radiotherapy (3DCRT) entails an increase of the healthy volumes irradiated with low doses, and the consequences of this fact should be analysed. This study tries to assess the suitability of one or another technique for the treatment of breast cancer patients with PTV volumes involving axillary and supraclavicular lymph nodes but not   the internal mammary chain. For this purpose, treatment plans of 80 patients that have been treated at our Institution with both techniques were analysed. First of all, pure dosimetric criteria were taken into account, for instance keep the dose in the organs at risk under the established limits. On the other hand, an estimation of the increase in the probability of developing secondary solid radio-induced tumours, due to low dose irradiation of healthy tissues, was done. Heart and pulmonary toxicities were also discussed according to the state of the art.