A biologia do câncer e discussão dos modelos de hipofracionamento de dose no tratamento de câncer de mama

Abstract

Radiotherapy is essential in the treatment of breast cancer, with hypofractionated and conventional fractionation models widely debated by international institutions. Studies demonstrate that both models are equivalent in terms of acute and late toxicity, although hypofractionation, in some cases, shows a lower incidence of side effects compared to conventional fractionation. Furthermore, hypofractionation can reduce the total cost of treatment due to the smaller number of sessions, which is particularly advantageous in low-income areas where economic conditions and tumor staging may influence the choice of radiotherapy model, as well as regional clinical practices. However, for an accurate comparison between the two models, several factors need to be considered, such as tumor type and stage, lymph node involvement, the use of boost radiotherapy, and individual patient characteristics. More long-term studies with follow-ups of over 10 years are needed to confirm the advantages of hypofractionation. The scarcity of research including boost radiotherapy for breast cancer and the small sample sizes in many studies limit the robustness of the results. This study, therefore, provides a detailed comparative analysis between conventional and hypofractionated models, highlighting their equivalence and the potential benefits of disseminating and standardizing hypofractionation as a global standard in breast cancer treatment. It is concluded that if hypofractionation was adopted as the standard, certain advantages, such as reduced treatment time, total treatment cost, and a general reduction in adverse effects, would bring significant benefits to patients and healthcare systems alike.