1. Combined Visual and Semiquantitative Evaluation Improves Outcome Prediction by Early Midtreatment 18F-FDG PET in Diffuse Large B-Cell Lymphoma
- Author
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Chirayu U. Auewarakul, Juliano Julio Cerci, Stefano Fanti, Claudio Meneghetti, Diana Paez, Linda Jorgov, Monica Celli, Tamás Györke, Robert Carr, Charity Gorospe, Francisca Redondo, and Györke T, Carr R, Cerci JJ, Meneghetti C, Redondo F, Celli M, Gorospe C, Auewarakul CU, Jorgov L, Paez D, Fanti S.
- Subjects
interim PET ,business.industry ,Newly diagnosed ,medicine.disease ,Predictive value ,Interim pet ,Treatment failure ,SUV ,18f fdg pet ,03 medical and health sciences ,0302 clinical medicine ,DLBCL ,030220 oncology & carcinogenesis ,medicine ,Deauville criteria ,Cutoff ,Radiology, Nuclear Medicine and imaging ,Nuclear medicine ,business ,Outcome prediction ,Diffuse large B-cell lymphoma ,030215 immunology - Abstract
The purpose of this study was to assess the predictive and prognostic value of interim FDG PET (iPET) in evaluating early response to immunochemotherapy after 2 cycles (PET-2) in diffuse large B-cell lymphoma (DLBCL) by applying 2 different methods of interpretation: the Deauville visual 5-point scale (5-PS) and a change in SUV (ΔSUV) by semiquantitative evaluation. Methods: In total, 145 patients with newly diagnosed DLBCL underwent pretreatment PET and PET-2 assessment. PET-2 was classified according to both 5-PS and percentage ΔSUV. Receiver-operating-characteristic analysis was performed to compare the accuracy of the 2 methods for predicting progression-free survival. Survival estimates, based on each method separately and combined, were calculated for iPET-positive (iPET+) and iPET-negative (iPET-) groups and compared. Results: Both with 5-PS and with ΔSUV-based evaluations, significant differences were found between the progression-free survival of iPET- and iPET+ patient groups (P < 0.001). Visually, the best negative predictive value (NPV) and positive predictive value (PPV) occurred when iPET was defined as positive if the Deauville score was 4-5 (89% and 59%, respectively). Using the 66% ΔSUV cutoff reported previously, NPV and PPV were 80% and 76%, respectively. ΔSUV at the 48.9% cutoff, reported for the first time here, produced 100% specificity along with the highest sensitivity (24%). The 5-PS and a semiquantitative ΔSUV of less than 48.9% for each PET-2 gave the same PET-2 classification (positive or negative) in 70% (102/145) of all patients. This combined classification delivered NPV and PPV of 89% and 100%, respectively, and all iPET+ patients failed to achieve or remain in remission. Conclusion: In this large consistently treated and assessed series of DLBCL patients, iPET had good prognostic value interpreted either visually or semiquantitatively. We determined that the most effective ΔSUV cutoff was 48.9% and that when combined with 5-PS assessment, a positive PET-2 result was highly predictive of treatment failure.cases, and MRI in 92.5% of cases; no false negative cases were observed. These results suggest the use of PET/CT as a unique diagnostic imaging tool after CCRT, to correctly assess residual and progression disease.
- Published
- 2019