Pediatric Hodgkin Lymphoma

Abstract

We investigated the prognostic value of interim 18F-FDG PET/CT (PET-2) in pediatric Hodgkin lymphoma (pHL), evaluating both visual and semiquantitative analysis.Thirty pHL patients (age ≤16) underwent serial 18F-FDG PET/CT: at baseline (PET-0), after 2 cycles of chemotherapy (PET-2) and at the end of first-line chemotherapy (PET-T). PET response assessment was carried out visually according to the Deauville Score (DS), as well as semiquantitatively by using the semiquantitative parameters reduction from PET-0 to PET-2 (ΔΣSUVmax0–2, ΔΣSUVmean0–2). Final clinical response assessment (outcome) at the end of first-line chemotherapy was the criterion standard, considering patients as responders (R) or nonresponders (NR). Disease status was followed identifying patients with absence or relapsed/progression disease (mean follow-up: 24 months, range 3–78).Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of visual and semiquantitative assessment were calculated; furthermore, Fisher exact test was performed to evaluate the association between both visual and semiquantitative assessment and outcome at the end of the first-line chemotherapy. The prognostic capability of PET-2 semiquantitative parameters was calculated by ROC analysis and expressed as area under curve (AUC). Finally, progression-free survival (PFS) was analyzed according to PET-2 results based on the 5-point scale and semiquantitative criteria, using the Kaplan–Meier method.Based on the outcome at the end of first-line chemotherapy, 5 of 30 patients were NR, the remnant 25 of 30 were R. Sensitivity, specificity, PPV, NPV, and accuracy of visual analysis were 60%,72%,30%,90%,70%; conversely, sensitivity, specificity, PPV, NPV, and accuracy of semiquantitative assessment were 80%, 92%, 66.7%, 95.8%, 90%. The highest AUC resulted for ΔΣSUVmax0–2 (0.836; cut-off <12.5; sensitivity 80%; specificity 91%). The association between ΔΣSUVmax0–2 and outcome at the end of first-line chemotherapy resulted to have a strong statistical significance (P = 0.0026). Both methods demonstrated to influence PFS, even if the semiquantitative assessment allowed a more accurate identification of patients with a high risk of treatment failure (P = 0.005).Our preliminary results showed that PET-2 visual assessment, by using Deauville criteria, can be improved by using the semiquantitative analysis. The SUV max reduction (ΔΣSUVmax0–2) evaluation might provide a support for the interpretation of intermediate scores, predicting with good confidence those patients who will have a poor outcome and require alternative therapies.

Are Semiquantitative Methods Superior to Deauville Scoring in the Monitoring Therapy Response for Pediatric Hodgkin Lymphoma?

“…We enrolled 52 patients, a relatively large number for a single-center study carried out in a high-volume referral center and in a context where HL incidence is lower in our region compared to other regions of our country (BLINDED) [ 24 ]. However, when compared to other studies conducted on the same subject, the sample size was generally low [ 10 , 24 , 25 , 26 , 27 ].…”

Early Evaluation of Immunotherapy Response in Lymphoma Patients by 18F-FDG PET/CT: A Literature Overview

“…Immune CI represents a new challenge for medical imaging, for both morphological and functional methods [ 12 ]. If the use of 18F-FDG PET/CT in stadiation, treatment response evaluation and follow up in patients with lymphoma is well established, some concerns remain about PET evaluation in immunotherapy because of the possibility to encounter hyperprogression/pseudoprogression, as it is well documented for solid tumors [ 31 ].…”

Tyrosine-Kinase Inhibitors Therapies with Mainly Anti-Angiogenic Activity in Advanced Renal Cell Carcinoma: Value of PET/CT in Response Evaluation

“…FDG accumulation rate can be semi-quantitatively measured by the maximum standardized uptake value (SUVmax), which is an indirect estimate of the glycolytic activity in the most active pixel within the lesion. Nowadays, this parameter is employed in clinical practice to support the qualitative PET imaging interpretation, achieving the best results in the majority of cancer type also for its prognostic value and treatment guidance [ 69 , 70 ].…”