TY - JOUR T1 - Validation of a Multifocal Segmentation Method for Measuring Metabolic Tumor Volume in Hodgkin Lymphoma JF - Journal of Nuclear Medicine Technology JO - J. Nucl. Med. Technol. SP - 30 LP - 35 DO - 10.2967/jnmt.119.231118 VL - 48 IS - 1 AU - Mariana R. Camacho AU - Elba Etchebehere AU - Natalia Tardelli AU - Marcia T. Delamain AU - Aline F.A. Vercosa AU - Maria E.S. Takahashi AU - Sergio Q. Brunetto AU - Irene G.H.L. Metze AU - Cármino A. Souza AU - Juliano J. Cerci AU - Celso D. Ramos Y1 - 2020/03/01 UR - http://tech.snmjournals.org/content/48/1/30.abstract N2 - Quantification of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) can be time-consuming. We evaluated the performance of an automatic multifocal segmentation (MFS) method of quantification in patients with different stages of Hodgkin lymphoma, using the multiple VOI (MV) method as reference. Methods: This prospective bicentric study included 50 patients with Hodgkin lymphoma who underwent staging 18F-FGD PET/CT. The examinations were centrally reviewed and processed with commercial MFS software to obtain MTV and TLG using 2 fixed relative thresholds (40% and 20% of SUVmax) for each lesion. All PET/CT scans were processed using the MV and MFS methods. Interclass correlation coefficients and Bland–Altman plots were used for statistical analysis. Repeated calculations of MTV and TLG values by 2 observers with different degrees of PET/CT imaging experience were used to ascertain interobserver agreement on the MFS method. Results: The means and SDs obtained for the MTV with MV and MFS were, respectively, 736 ± 856 mL and 660 ± 699 mL for the 20% threshold and 313 ± 359 mL and 372 ± 434 mL for the 40% threshold. The time spent calculating the MTV was much shorter with the MFS method than with the MV method (median time, 11.6 min [range, 1–30 min] and 64.4 min [range, 1–240 min], respectively), especially in patients with advanced disease. Time spent was similar in patients with localized disease. There were no statistical differences between the MFS values obtained by the 2 different observers. Conclusion: MTV and TLG calculations using MFS are reproducible, generate similar results to those obtained with MV, and are much less timing-consuming. Main differences between the 2 methods were related to difficulties in avoiding overlay of VOIs in the MV technique. MV and MFS perform equally well in patients with a small number of lesions. ER -