RESUMO
Despite improvements in radiotherapy, radioresistance remains an important clinical challenge. Radioresistance can be mediated through enhanced DNA damage response mechanisms within the tumour or through selective pressures exerted by the tumour microenvironment (TME). The effects of the TME have in recent times gained increased attention, in part due to the success of immune modulating strategies, but also through improved understanding of the downstream effects of hypoxia and dysregulated wound healing processes on mediating radioresistance. Although we have a better appreciation of these molecular mechanisms, efforts to address them through novel combination approaches have been scarce, owing to limitations of photon therapy and concerns over toxicity. At the same time, proton beam therapy (PBT) represents an advancement in radiotherapy technologies. However, early clinical results have been mixed and the clinical strategies around optimal use and patient selection for PBT remain unclear. Here we highlight the role that PBT can play in addressing radioresistance, through better patient selection, and by providing an improved toxicity profile for integration with novel agents. We will also describe the developments around FLASH PBT. Through close examination of its normal tissue-sparing effects, we will highlight how FLASH PBT can facilitate combination strategies to tackle radioresistance by further improving toxicity profiles and by directly mediating the mechanisms of radioresistance.
Assuntos
Neoplasias , Terapia com Prótons , Radioterapia (Especialidade) , Humanos , Neoplasias/radioterapia , Seleção de Pacientes , Microambiente TumoralRESUMO
The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of early and locally-advanced non-small-cell lung cancer (NSCLC) was published in 2017, and covered the diagnosis, staging, management and treatment of both early stage I and II disease and locally-advanced stage III disease. At the ESMO Asia Meeting in November 2018, it was decided by both the ESMO and the Korean Society of Medical Oncology (KSMO) to convene a special face-to-face guidelines meeting in 2019 in Seoul. The aim was to adapt the ESMO 2017 guidelines to take into account potential differences related to ethnicity, cancer biology and standard practices associated with the treatment of locally-advanced, unresectable NSCLC in Asian patients. These guidelines represent the consensus opinions reached by those experts in the treatment of patients with lung cancer who represented the oncology societies of Korea (KSMO), China (CSCO), India (ISMPO), Japan (JSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and it was independent of both local current treatment practices and the treatment availability and reimbursement situations in the individual participating Asian countries.