Conformal radiation therapy represents a new challenge for radiation oncologists. It offers the prospect of either increasing the radiation dose to target tissues while delivering a similar dose to organs at risk, or reducing the dose to organs at risk while maintaining the dose to target tissues. First, lymph node areas at risk are established using the available data from pathological examination of surgical specimens and/or pattern of locoregional relapse. Then, based on a three-dimensional description of the anatomical regions where the areas at risk are located, guidelines for the...