Advantages of Post-Mastectomy Proton Beam Therapy in a Breast Cancer Patient With Pectus Excavatum

Abstract

Pectus excavatum (PE) is a chest wall deformity that can complicate the delivery of radiation therapy (RT) for breast cancer. This case report highlights the potential benefits of proton beam therapy (PBT) for these patients. We describe a case of a 79-year-old woman with PE who required post-mastectomy chest wall RT. Treatment plans were generated to deliver 45 Gy in 25 fractions with either PBT or conventional conformal photon RT. A 10-Gy boost to the post-mastectomy scar was used for both plans. A dosimetric benefit was observed for organs at risk with the PBT plan compared to the photon plan. PBT reduced mean doses to the lungs by more than 70% and to the heart by greater than 95%. The patient was treated with PBT with minimal acute toxicities. With the challenging chest anatomy of PE, PBT was selected as the treatment of choice for post-mastectomy radiation. The superior dosimetry can decrease the risks of post-treatment cardiac and pulmonary toxicities.




J Med Cases. 2017;8(3):98-101
doi: https://doi.org/10.14740/jmc2781w