Large Segmentation Radiotherapy ± Deep Inspiration Breath Hold(DIBH) for Left Breast Cancer

Inclusion criteria

• 18-70 years old, female, life expectancy > 5 years
• ECOG 0, 1, 2 points
• Pathologically diagnosed with left breast cancer and underwent breast-conserving surgery or modified radical mastectomy
• The patient will receive radiation therapy to the entire breast or chest wall ± the lymphatic drainage area above and below the clavicle ± the lymphatic drainage area in the axilla.
• No prior neoadjuvant chemotherapy or breast reconstruction.
• No active cardiac disease, myocardial infarction, or congestive cardiac failure at baseline.
• Patients can hold their breath for at least 30 seconds after training
• Patients who can be followed up and agree to follow the plan.
• Sign the consent form.

Exclusion criteria

• Lesions were observed on both sides of the breast.
• Diagnosis could not be confirmed by pathology.
• Distant metastasis was identified.
• The patient had undergone neoadjuvant chemotherapy or breast reconstruction surgery.
• Severe cardiac insufficiency; myocardial infarction or uncorrected unstable cardiac arrhythmia or uncorrected unstable angina within the last 3 months; or pericardial disorders
• The patient's New York Heart Association (NYHA) cardiac classification is within categories 2-4.
• A history of chronic lung disease, including conditions that may contribute to ductal dilatation, such as chronic obstructive pulmonary disease (COPD) and interstitial pneumonia.
• Previous mediastinal radiotherapy.
• Previous or concurrent second primary malignant tumor (except skin cancer that is not a malignant black pigmented tumor, papillary/follicular carcinoma of the thyroid, carcinoma in situ of the cervix, and contralateral non-invasive breast cancer).
• Irradiation of the lymphatic drainage area of the internal breast is required.