乳癌・術後照射の実践的テクニック（1）

A practical technique for the postoperative radiotherapy in breast cancer

前回まで領域リンパ節照射（regional nodal irradiation：RNI）やセンチネルリンパ節生検（SNB）陽性で腋窩郭清省略時の照射について述べてきたが，今回からは乳癌術後照射の手技について実践的視点から解説したい。

Radiation treatment（RT）fields for postoperative breast cancer patients have been historically designed mainly using bony landmarks. However, during the last decade treatment planning has dramatically changed from 2D to 3D according to advances in RT technologies. Currently, accurate and reasonable delineation of target volumes and organs at risk（OAR） on CT images is the mainstay in RT planning. Among several anatomy-based contouring atlases, ESTRO consensus guidelines were chosen in this paper and discussed in detail. In addition, OAR delineation and primary and secondary goal of absorbed dose in target volumes proposed by RTOG were introduced for reference.