Immobilization-assisted abdominal deep inspiration breath-hold in post-mastectomy radiotherapy of left-sided breast cancer with internal mammary chain coverage

Meiqin Chen, Shoumei Zang, Hao Yu, Lihua Ning, Huijie Huang, Luyi Bu, Jia Ge, Mengyou Xu, Qiuying Tang, Feng Zhao, Guorong Yao, Senxiang Yan