Abstract P099

PET/CT Response Assessment in Pediatric Hodgkin Lymphoma. Deauville Score 3 Does it really reflect Negativity?

Background: FDG PET is required for the staging and response evaluation of pediatric Hodgkin lymphoma. The study aims to evaluate the outcome of pediatric patients with Hodgkin's lymphoma based on interim PET CT assessments of their early response following second-cycle chemotherapy using the Deauville score (DS). To determine whether DS 3 is providing an adequate or inadequate response. Methods: A retrospective analysis of 504 pediatric patients with classic Hodgkin lymphoma who were treated with a chemotherapy protocol based on the Euro-Net protocol at the Children Cancer Hospital Egypt from March 2019 till the end of October 2022.

Results: While adequate response DS 1/2 and DS 3 have nearly the same 3-year event-free survival (EFS) of 91.9% and 91.5%, respectively, compared to those patients with inadequate response DS 4/5, who showed an EFS of 80.4% [p-value, 0.001], patients with a DS 3 at interim PET evaluation were considered negative as DS 1/2. Patients of DS 3 group who did not receive radiotherapy had a much worse 3 years EFS by the existence of positive B symptoms, an ESR> 30, or an advanced stage. Radiation therapy did not improve the 3-year EFS in patients with an inadequate response (DS4/5) and poor prognostic characteristics. They still need more advanced treatment.

Conclusion: DS 1/2 and DS 3 had about the same 3-year EFS, which is better than the three-year EFS of patients with DS 4/5. Therefore, we can classify DS 3 as having negative FDG PET CT uptake.

Keywords: Hodgkin lymphoma, pediatric, interim FDG PET-CT, Deauville criteria, Euro-Net protocol.

Authors

Emad Moussa, Asmaa Hamoda, samah semary, maram salama, mona fakhry, maha mehesen, madeeha elwakeelc, eman naguib, amr elnashar, asmaa Attia, mohamed sedky