Deep-Inspirational Breath-Hold (DIBH) Technique in Left-Sided Breast Cancer: An Institutional Review

Abstract
Purpose: The study of clinical effectiveness of deep-inspirational breath-hold (DIBH) in left breast cancer radiotherapy (RT) was aimed at focusing on dosimetry and organs at risk (OARs) evaluation. A retrospective study was conducted to assess the heart and ipsilateral lung V30 for DIBH technique and to compare with free breathing (FB) technique. Clinical data shows that by increasing the inhalation amplitude value (cm), the maximum heart distance decreases in the treatment field. Materials and Methods: Thirty left-sided breast and chest wall patients were CT scanned on 4DCT with DIBH. These patients were chosen for the DIBH technique with the ability to hold their breath for more than 20 seconds. Radiotherapy of these patients was planned using field-in-field planning technique, and OAR doses were observed using the institutionally specified DIBH protocol. Results: The mean heart dose was less than 3Gy. Whereas V2Gy and V10Gy were less than 30% and 5%. The mean ipsilateral lung dose was 7.59 Gy. Ipsilateral lung V30 was less than 25% with ±10% margins. It is found that by increasing the inhaling amplitude (cm) heart involvement in the tangential treatment field decreases. Conclusion: DIBH is an easy and highly efficient treatment technique for reducing the mean dose of the heart and V30 of ipsilateral lung. The maximum heart distance decreases as the baseline of inhalation increases due to heart doses.