Breast irradiation in the lateral decubitus position: technique of the Institut Curie.

Breast irradiation in the lateral decubitus (LD) position is a technique used at the Institut Curie for more than 30 years in the breast-conserving management of patient with breast cancer. This technique is described in detail in this article. The patient's position allows the breast to flatten over a support, hence providing a rather homogeneous thickness throughout the treated volume. Dose at mid-thickness on the beam axis can be easily determined from entrance and exit dose measurements. Disadvantages and advantages of the LD technique are discussed. We presently recommend this technique for patients with large breasts (more than 6 cm thickness in LD position).