Abstract
BACKGROUND: Breast cancer is the most common cancer and the leading cause of death in women. The deep inspiration breath-hold (DIBH) technique helps reduce the dose received by the heart and lungs in breast cancers during adjuvant radiotherapy (RT). We present the dosimetry of heart and lungs with DIBH technique, reproducibility, and ease of execution. MATERIALS AND METHODS: This is a prospective study among breast cancer patients planned for adjuvant RT following either breast conservation or mastectomy. Patients received adjuvant RT to a dose of 42.5 Gy/16 Fr to the chest wall/whole breast followed by a boost of 10 Gy/5 Fr for breast conservation surgery patients with either three-dimensional conformal RT or volumetric modulated arc therapy technique. The dosimetric parameters such as lung mean dose, heart mean dose, and V25 Gy were compared between DIBH and free-breathing (FB) scans. Data were analyzed using SPSS software, and p -value <0.05 was considered statistically significant. RESULTS: The study was conducted from September 2018 to August 2020, and 32 patients were included. The compliance to the DIBH technique was good. The dose received by ipsilateral lung V20 (17 vs. 25%) and mean dose (9 vs. 12 Gy) were significantly lower in DIBH compared with FB ( p < 0.001). The V5 (31 vs. 15%), V25 (9 vs. 2%), and mean dose (7 vs. 3.3 Gy) to the heart were much higher in FB compared with DIBH ( p < 0.001). CONCLUSION: DIBH-based RT treatment delivery for breast cancer patients requiring adjuvant RT showed good compliance and offers a significant reduction in radiation dose to the heart and lung.