Optimal gross tumor volume definition in lung-sparing intensity modulated radiotherapy for pleural mesothelioma: an in silico study

Abstract

Background: The gross tumor volume (GTV) definition for malignant pleural mesothelioma (MPM) is ill-defined. We therefore investigated which imaging modality is optimal: computed tomography (CT) with intravenous contrast (IVC), positron emission tomography-CT (PET/CT) or magnetic resonance imaging (MRI).

The Use of Radiation Therapy for the Treatment of Malignant Pleural Mesothelioma: Expert Opinion from the National Cancer Institute Thoracic Malignancy Steering Committee, International Association for the Study of Lung Cancer, and Mesothelioma Applied Research Foundation

“…Obtaining a positron emission tomography (PET) scan before contouring can be considered for restaging and for optimal target delineation. In addition, magnetic resonance imaging (MRI) scans have been demonstrated to be the superior imaging modality for the detection of T3 to T4 disease, 2,3 as well as in definition of the pleural gross tumor volume (GTV) 4 and thus should also be incorporated into the imaging regimen when appropriate and available. We particularly recommend obtaining an MRI scan when a lung-sparing approach is used in the context of gross disease, in which case the T1, T2, fat-suppressing sequences, and diffusion-weighted MRI can greatly aid in the target delineation.…”

“…The prescribed dose per fraction is 1.8 Gy, and the total prescribed dose is 50. 4 Gy. An optional concomitant boost to 60 Gy for gross residual disease may be incorporated if normal tissue constraints can be met.…”

Progress and challenges in Mesothelioma: From bench to bedside

“…Moreover, direct, histological assessment of the mediastinum should be considered, particularly in light of emerging data regarding the prognostic importance of mediastinal nodal involvement in MPM (see 'Staging'). Importantly, MRI also allows more precise estimation of pleural tumour volume [16] and acquisition of functional data [17] that may be useful in future T-staging and early detection strategies. Local Anaesthetic Thoracoscopy (LAT) images recorded in the same patient demonstrating widespread parietal pleural tumour (some highlighted by white arrows) after complete evacuation of the large pleural effusion.…”

Zaštita Od Zračenja Pacijenata U Toku Radioterapijskog Tretmana Primjenom Modernih Tehnika Zračenja

“…Iradijacija pleure zbog malignog mezotelioma ranije je značila istovremenu isporuku visokih doza i na zdravi parenhim pluća. Istraživanja govore u prilog dužeg perioda bez bolesti (DFS) nakon iradijacije IMRT/RA tehnikama, zahvaljujući isporuci veće ukupne doze i signifikantne poštede pluća, bilo da su tretirani adjuvantno ili kao definitivni tretman u odnosu na pacijente koji nisu radioterapijski tretirani [18][19][20]. Za razliku od lokoregionalno uznapredovalih tumora pluća, rani stadiji karcinoma pluća standardno se liječe operativno, međutim, za pacijente koji su medicinski inoperabilni zbog komorbiditeta, standard u liječenju je stereotaksijska iradijacija (SBRT) [21][22][23][24][25][26][27].…”