Core Viewpoint - Proton therapy is redefining breast cancer recovery by providing effective treatment without compromising the patient's future health and quality of life [1][5]. Group 1: Patient Experience and Benefits - A young HER2-positive breast cancer patient successfully underwent proton therapy, experiencing minimal side effects and expressing gratitude for the treatment's impact on her quality of life [1]. - Proton therapy has been successfully implemented for multiple breast cancer patients at Guangzhou Taihe Cancer Hospital, emphasizing its role in enhancing both longevity and quality of life [1]. Group 2: Suitable Patient Demographics - Proton therapy is particularly beneficial for left-sided breast cancer patients due to its ability to significantly reduce radiation exposure to the heart and coronary arteries [3]. - Patients requiring irradiation of the internal mammary lymph nodes, those with unique anatomical structures, young patients under 50, and those needing re-irradiation for local recurrence can also benefit from proton therapy [3][4]. Group 3: Advantages of Proton Therapy - The unique physical properties of proton therapy, such as the Bragg Peak, allow for precise targeting of tumors while minimizing damage to surrounding healthy tissues, which is crucial for protecting vital organs [5]. - Proton therapy reduces the risk of secondary cancers by limiting unnecessary radiation exposure to healthy tissues, making it especially important for younger patients with longer life expectancies [5][6]. - The treatment offers better dose distribution, potentially improving local control rates for complex cases [5]. Group 4: Treatment Applications - Proton therapy serves as an adjunctive treatment post-surgery, effectively targeting residual cancer cells while maximizing protection of the heart and lungs [7]. - It can be used as a curative option for patients unable to undergo surgery due to severe comorbidities, either alone or in combination with systemic therapies [8]. - Proton therapy can be integrated with other treatments, such as chemotherapy and targeted therapies, to enhance local toxicity control and optimize treatment outcomes [9].