PT  - JOURNAL ARTICLE
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
TI  - Validation of a Multifocal Segmentation Method for Measuring Metabolic Tumor Volume in Hodgkin Lymphoma
AID  - 10.2967/jnmt.119.231118
DP  - 2020 Mar 01
TA  - Journal of Nuclear Medicine Technology
PG  - 30--35
VI  - 48
IP  - 1
4099  - http://tech.snmjournals.org/content/48/1/30.short
4100  - http://tech.snmjournals.org/content/48/1/30.full
SO  - J. Nucl. Med. Technol.2020 Mar 01; 48
AB  - 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.