Factors Affecting the Effectiveness of DIBH (Deep Inspiratory Breath Hold) in Patients with Left Breast Cancer: A Narrative Review

Deep Inspiratory Breath Hold (DIBH) has become a valuable technique in left-breast cancer radiotherapy, offering the possibility to reduce radiation exposure to organs at risks (OARs) and minimize the risk of cardiac complications. This treatment method involves stopping the breathing of patients during irradiation in order to temporarily distance the heart from the radiation field, which reduces potential cardiac risks and other complications. To identify factors that may affect the effectiveness of DIBH treatment, we analyzed the most important 5-year studies published in the PubMed database. Research shows that DIBH reduces the radiation dose to the heart and lungs. However, the effectiveness of DIBH is determined by a variety of factors, including the patient's training, cooperation, anatomical features, age, and choice of radiotherapy technique. Additionally, cardiovascular risk factors, such as diabetes, smoking, and hypertension, can be impactful to the effectiveness and potential complications of DIBH. Moreover, if a patient has a substantial level of depression or anxiety, then they may be potentially disqualified from the DIBH treatment method. In addition to this, a lack of consent and/or fear may also disqualify a patient from DIBH treatment. Careful patient selection, comprehensive training, and optimization of treatment parameters are essential to maximize the benefits of DIBH whilst minimizing any potential side effects. DIBH enhancement techniques, such as IMRT and VMAT, also have an important role to play. The purpose of this narrative review article is to summarize the factors affecting the efficacy and side effects of DIBH in radiation therapy for left-breast cancer, with the aim of optimizing its clinical application while minimizing side effects. Patients who are likely to benefit most from DIBH are young women in good medical condition, able to cooperate with the procedure, and with smaller breasts. The increase in the estimated 10-year patient survival is significantly influenced by cardiovascular problems, so patients without diabetes and metabolic syndrome, and non-smokers, will benefit the most. An estimated 50-70% of breast cancer patients are likely to benefit from DIBH, and in the best case, it can result in a 50% reduction in the risk of cardiac problems after photodynamic therapy (PDT).