Breast cancer radiotherapy has a clear benefit for both long-term survival and local recurrence rate. However, there is still much concern about the early radiation-induced heart toxicity. This article aimed to clarify the impact of certain cardiac biomarkers and strain echocardiographic imaging on the detection of early cardiac dysfunction. Several studies that reported changes in either echocardiographic and/or serum levels measurements after breast radiotherapy were searched. Despite the established role of cardiac biomarkers to predict late cardiotoxicity after radiotherapy, data concerning early cardiac damage are still lacking. Furthermore, although strain echocardiography represents a specific tool for the detection of cardiac morbidity in certain diseases, much interest concerns its role in the prediction of early heart failure after radiotherapy. Identification of new tools for the detection of early cardiotoxicity after breast radiotherapy may minimize the side-effects of therapeutic modalities in the clinical setting.

Backround/Aim: Adjuvant radiotherapy in patients with cancer of the left breast may lead to impaired cardiac function. The aim of our prospective study is to evaluate (i) doses to the irradiated volume of the heart and its substructures and (ii) determine whether their correlation with changes in strain echo measurements contribute to the prediction of subclinical heart morbidity. Patients and Methods: Twenty-five patients were enrolled in our study. We retrospectively assessed the radiation doses to the whole heart, left anterior descending artery (LAD) and left ventricle (LV). Results: The mean heart dose (MHD) was 152 cGy (SD=50.56 cGy) and the range was 74-279 cGy. The LAD was the most exposed structure, with a mean dose of 448.91 cGy (SD=490.53 cGy) and range of 120-2,057cGy. Finally, the mean LV dose was 149.12 cGy (SD=69.57) with a range of 63-317 cGy. Conclusion: The early results of our study showed low radiation exposure of the whole heart and left ventricle, and higher exposure of the LAD. The data that will emerge from the evaluation of strain echo parameters should show whether these associations might be useful in clinical practice for the prediction of early subclinical cardiac changes.

Background: Breast cancer (BC) is the most common malignancy in females, accounting for the majority of cancer-related deaths worldwide. There is well-established understanding about the effective role of radiotherapy (RT) in BC therapeutic strategies, offering a better local–regional control, prolonged survival, and improved quality of life for patients. However, it has been proven that conventional RT modalities, especially in left-sided BC cases, are unable to avoid the administration of high RT doses to the heart, thus resulting in cardiotoxicity and promoting long-term cardiovascular diseases (CVD). Recent radiotherapeutic techniques, characterized by dosimetric dose restrictions, target volume revision/modifications, an increased awareness of risk factors, and consistent follow-ups, have created an advantageous context for a significant decrease inpost-RT CVD incidence. Aim: This review presents the fundamental role of current cardioprotective strategies in the prevention of cardiotoxic effects in left-BCRT. Material and Methods: A literature search was conducted up to January 2023 using the Cochrane Central Register of Controlled Trials and PubMed Central databases. Our review refers to new radiotherapeutic techniques carried out on patients after BC surgery. Specifically, a dose evaluation of the heart and left anterior descending coronary artery (LADCA) was pointed out for all the included studies, depending on the implemented RT modality, bed positioning, and internal mammary lymph nodes radiation. Results: Several studies reporting improved heart sparing with new RT techniques in BC patients were searched. In addition to the RT modality, which definitely determines the feasibility of achieving lower doses for the organs at risk (OARs), better target coverage, dose conformity and homogeneity, and the patient’s position, characteristics, and anatomy may also affect the evaluated RT dose to the whole heart and its substructures. Conclusions: Modern BC RT techniques seem to enable the administration of lower doses to the OARs without compromising on the target coverage. The analysis of several anatomical parameters and the assessment of cardiac biomarkers potentiate the protective effect of these new irradiation modalities, providing a holistic approach to the radiation-associated risks of cardiac disease for BC patients. Despite technological advances, an inevitable cardiac radiation risk still exists, while adverse cardiac events may be observed even many years after RT. Studies with longer follow-ups are required in order to determine the effectiveness of modern breast RT techniques.

Breast cancer heterogeneity reflects the complex biology of this disease. Breast cancer subtypes, as identified either by immunohistochemistry (IHC) or by gene expression analysis, present different molecular characteristics and prognosis. In this context, molecular imaging techniques providing functional information, contribute in evaluating response to treatment and long-term prognosis among different subtypes. Nuclear imaging diagnosis modalities play an important role for conducting research on cancer biology and developing new treatment approaches. Positron Emission Tomography (PET) is a radionuclide based imaging method that has the potential to locate the tumor, define its staging, and monitor its response to treatment. In the current study, we will review the utility of the most widely used molecular imaging technique, ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET, in order to determine the relationship between standardized uptake values (SUVs) and immunohistopathological factors, as well as to clarify whether PET is able to predict breast cancer phenotypes. Moreover, we will discuss the rising development of new radiopharmaceuticals in PET imaging, such as ¹⁸F-fluoro-17-estradiol (FES), ¹⁸F-fluoro-l-thymidine (FLT), ¹⁸F-fluoromisonidazole (FISO), and ⁸⁹Zr-immuno-PET, which give more information about tumor characteristics. In order to improve clinical decision making, enabling hereafter more successful individualized therapies, it is imperative to combine PET radiopharmaceuticals and imaging techniques of critical biologic and pathologic phenomena, including ER, PR and HER2 expression, angiogenesis, hypoxia, apoptosis and metabolic changes in the microenviroment of breast tumors.