A technique of partial breast irradiation utilizing proton beam radiotherapy: comparison with conformal x-ray therapy.

Purpose: To develop a breast immobilization system and clinical technique to deliver partial breast irradiation with a proton beam and compare dose distributions using proton therapy and conformal x-rays.

Methods: A clinical technique to provide reproducible breast immobilization was developed. Breast immobilization begins by fitting each patient with a treatment brassiere.