Abstract
We evaluated the usefulness of interim 18F-FDG PET/CT for risk stratification using different cutoff values of the Deauville 5-point scale (5-DS) in DLBCL patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). One hundred and fifty patients underwent interim (I-) and end of treatment (EOT-) PET/CT scans. Applying the conventional 5-DS cutoff value of scores 4 to 5 at interim, there was no significant difference in progression free survival (PFS) between I-PET negative and I-PET positive patients. In comparison, PFS was inferior in patients with a score of 5 on I-PET scan compared with those with a score in between 1 to 4 (28.6% vs. 78.7%, p < .0001), and positive predictive value (71.4%) was improved compared to that obtained using cutoff value of scores 4 to 5 (34.9%). Our study shows that a cutoff score of 5 at interim has an alternative clinical implication for identifying patients at a significant risk.
Acknowledgements
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2016R1D1A1A02937028).
Potential conflict of interest
Disclosure forms provided by the authors are available with the full text of this article online at https://doi.org/10.1080/10428194.2017.1339877.