Room: Exhibit Hall
Purpose: Radiotherapy to breast cancer with large pendulous breasts presents dosimetric challenges when the whole breast and supraclavicular lymph nodes are involved. This study developed and implemented the clinical workflow of three-field prone breast radiotherapy treatment, which includes patient simulation, treatment planning (TP) and treatment delivery.
Methods: Varian kVue Access360â„¢ Prone Breast Couch top was used for prone three-field breast treatment. The treatment planning is performed in Eclipse treatment planning system (TPS). The 3-field monoisocentric plans were created for both the supine and prone CT scans. Target coverage, homogeneity, and organ at risk sparing were investigated for both supine and prone plans. For the daily setup, breast coverage was assessed in the room using light field and MV imaging was used at day 1 and weekly.
Results: Varian kVue Access360â„¢ Prone Breast Couch top has enabled a pendulous breasted woman with involvement of supraclavicular region to be treated in the prone position. Both supine and prone plans achieved acceptable coverage of the target. The percentage of ipsilateral lung receiving 20 Gy was substantially reduced for prone three-field treatment plan. Three-field prone breast radiotherapy appears to be dosimetrically equivalent to supine treatment with respect to target coverage, but the prone position decreases lung and heart dose. The workflow for three-field prone breast radiation therapy has been developed and the technique is ready to treat patients.
Conclusion: Prone breast treatment is used to reduce acute and late toxicities for large or pendulous breast patients. This study developed and implemented the clinical workflow of three-field prone breast radiotherapy treatment.