4DCT versus 4DPET/CT na avaliação do movimento respiratório no planeamento da radioterapia no cancro do pulmão de não pequenas células: revisão da literatura.

Introduction - One of the therapeutic approaches in non-small cell lung carcinoma (NSCLC) is concomitant chemotherapy and radiotherapy (RT). The planning of RT can be performed based on different imaging techniques, and several factors may influence their quality, including respiratory motion. Objectives - This study aims to: 1) assess the importance of 4DCT and 4DPET/CT for motion correction and target volume definition in planning RT for NSCLC; and 2) compare volume delimitation between PET/CT, 4DCT, and 4DPET/CT techniques, identifying their advantages and limitations. Methods - Literature review, using the PRISMA methodology for the selection of articles in PubMed and Science Direct databases and other sources (b-on and Google Scholar). Articles published between January 2014 and January 2020 were considered. Delineated volumes using 3D and 4D techniques were compared, assessing the impact of respiratory motion on image acquisition and subsequent RT planning. Results - 230 articles were obtained, but only five were eligible for the study. The 4DCT and 4DPET/CT techniques showed better results, decreasing motion artifacts. The volumes delimited by the various techniques under study were similar, although small variations were recorded when the 4D technique is not applied. Conclusion - Currently 4DPET/CT shows better results in the delimitation of target volumes for RT planning than the 4DCT technique. [ABSTRACT FROM AUTHOR]