Assessment of Left-sided Cardiac Sparing Through the Use of 3-dimensional Surface Matching-based Deep Inspiration Breath Hold and Active Breathing Control

Assessment of Left-sided Cardiac Sparing Through the Use of 3-dimensional Surface Matching-based Deep Inspiration Breath Hold and Active Breathing Control

The standard treatment for breast cancer is surgery followed by adjuvant breast radiation therapy in most cases. For left sided breast cancers, the heart dose delivered by the radiation treatment is often of particular concern. In order to spare the heart, different strategies are currently available, including active breathing control (ABC) and voluntary deep in inspiration breath hold (DIBH) (both strategies are currently being used at our centre). To perform accurate heart-sparing treatments, it is important to ensure that patients are positioned consistently. One available approach is through surface imaging which tracks the position of a portion of the skin surface, known as the AlignRT system (VisionRT Ltd, London, UK).

Inclusion Criteria:

• Women with diagnosis of left-sided breast malignancy
• Women who require left chest wall or breast irradiation status post mastectomy or lumpectomy
• Treatment with modified wide tangents to include IMCs
• Treatment with four-field technique
• Age >18 years
• Performance status ECOG <3
• Patient must be able to maintain a 30 second breath hold
• Conventional chest wall or breast radiation delivery dose of 50Gy/25 or hypofractionated chest wall/breast radiation delivery dose of 42.56Gy/16 with or without a boost

Exclusion Criteria:

• Right sided breast cancer patients
• Treatment with partial breast irradiation
• Previous left breast/chest wall irradiation
• Locally advanced breast cancer
• Pregnant patients
• Unable to follow commands