The Influence of Treatment Position (Prone vs. Supine) on Whole Breast Target

Radiotherapy after breast conserving therapy plays an important role in early stage breast cancer patients. It not only results in a reduction in local and regional recurrence but also decrease the death rate effectively. For adjuvant radiotherapy, supine positioning is the most common approach and has multiple advantages. Due to deformability and softness of the breast, during simulation and treatment in supine position, the breast stretches over the chest wall, especially in patients with large and pendulous glands. Thus the organs at risk (OARs) received dose increased. The radiotherapeutic toxicity are unavoidable. Some present studies show that the prone positioning of patients can improve dose homogeneity and reduce the dose distribution in OARs in patients with large and pendulous glands. Chinese women have relatively small breasts, the advantages of those have not been established. Therefore, investigators compared the parameters between supine and prone positions for whole breast irradiation after conserving surgery.

Inclusion Criteria:Breast cancer patients with T1-T2N0M0 stage who underwent radiation therapy after conserving surgeryexhibited normal arm movement aſter surgeryhad no chronic lung diseasesWritten informed consent formsExclusion Criteria:Breast cancer patients with radical surgerycould not exhibit normal arm movement after surgeryhad chronic lung diseasesrefused informed consent forms