Selective mediastinal node irradiation in non-small cell lung cancer in the IMRT/VMAT era: How to use E(B)US-NA information in addition to PET–CT for delineation?. Issue 2 (August 2016)

• Record Type: Journal Article
• Authors: Peeters, Stephanie T.; Dooms, Christophe; Van Baardwijk, Angela; Dingemans, Anne-Marie C.; Martinussen, Hanneke; Vansteenkiste, Johan; Decaluwé, Herbert; De Leyn, Paul; Yserbyt, Jonas; Nackaerts, Kristiaan; De Wever, Walter; Deroose, Christophe M.; De Ruysscher, Dirk
• Is Part Of: Radiotherapy and oncology. Volume 120:Issue 2(2016:Aug.)
• Page Start: 273
• Page End: 278
• Publication Date: 2016-08
• Subjects: Radiotherapy -- Non-small cell lung cancer (NSCLC) -- Endobronchial ultrasound (EBUS) -- Intensity-modulated radiotherapy (IMRT) -- Volumetric arc therapy (VMAT) -- PET–CT based delineation; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2016.05.023
• Languages: English
• ISSNs: 0167-8140

Abstract

Abstract: Background: FDG-PET–CT-based selective lymph node (LN) irradiation is standard using 3D-conformal techniques for locally advanced NSCLC. With newer techniques (intensity-modulated/volumetric-arc therapy (IMRT/VMAT)), the dose to non-involved adjacent LN decreases, which raises the question whether FDG-PET–CT-delineation is still safe. We therefore evaluated the impact of adding linear endosonography with needle aspiration (E(B)US-NA) to FDG-PET–CT in selective nodal irradiation. Methods: Based on literature data on sensitivity and specificity of E(B)US-NA in FDG-PET–CT-staged NSCLC, false negative (FN) rates for different constellations of CT, PET and E(B)US-NA were calculated. The algorithm was tested on consecutive patients with N2/N3 disease referred for radiotherapy in Leuven and Maastricht. Results: An algorithm determining when to include LN in the GTV is proposed, based on data from 5 meta-analyses. Adding E(B)US-NA to FDG-PET–CT decreases the FN-rate, but for PET-positive and E(B)US-negative LN, FN rates are still 14–16%. In Leuven 520 LN were analyzed, in Maastricht 364 LN; with E(B)US-NA a geographical miss was avoided in 2 (2/40 = 5%) and 1 (1/28 = 4%) patients, respectively. Conclusions: E(B)US-NA in addition to FDG-PET–CT for mediastinal staging decreases the risk of a geographical miss with 4–5%. The impact of this small decrease on survival is unknown. The proposed algorithm may guide the radiation oncologist when to include LN in the nodal GTV.