doi: 10.1097/01.HS9.0000547917.84919.5d
Advanced Stages

L. Rigacci, B. Puccini, A. Broccoli, A. Evangelista, D. Gioia, M. Dona, S. Kovalchuk, A. Santoro, M. Bonfichi, A. Re, C. Pagani, L. Mannelli, F. Zaja, U. Vitolo, M. Spina, A. Pulsoni, L. Nassi, C. Stelitano, F. Salvi, C. Rusconi, M. Tani, R. Freilone, E. Borsatti, P. L. Zinzani

On behalf of Fondazione Italiana Linfomi

Purpose: The clinical impact of positron emission tomography (PET) performed early during therapy in patients with advanced-stage Hodgkin lymphoma has confirmed its impact in progression free survival. It is disappointing the observation of a group of patients with negative interim-PET (i-PET) but with a positive PET at the end of induction therapy (e-PET). These patients underline that i-PET is not a perfect instrument and it could be very important to analyze their clinical or biological characteristics to identify them.

Patients and Methods: The phase II part of the multicenter HD0801 study involved 519 patients with advanced-stage de novo Hodgkin lymphoma who received an initial treatment with ABVD and underwent a i-PET. Patients with positive i-PET shifted to a salvage therapy and those with negative i-PET continued with standard treatment. Patients with negative i-PET were evaluated for response and patients with a positive e-PET were moved to a salvage therapy. The aim of this study was to evaluate clinical and biological characteristics of these patients.

Results: In all 409 were i-PET negative. Among them 16 interrupted the therapy for different causes, therefore 393 patients were evaluated with e-PET, 354 were negative and 39 were positive. Sixteen out 39 were submitted to a diagnostic biopsy and 15 were confirmed as HD; 23 did not performed biopsy due to technical difficulties or decision of the clinicians. Seventeen out 39 e-PET were reviewed according Deauville Score and in sixteen it was confirmed positive (10 DS 5, 6 DS 4) in 1 case was unvaluable. With the exception of LDH value at diagnosis no clinical characteristics were significantly different in comparison with e-PET negative patients. The survival of e-PET positive patients was very disappointing 78% at 36 months in comparison either with negative e-PET or with positive i-PET.

Conclusion: Positive e-PET represents a very bad prognostic event even in comparison with i-PET positive patients salvaged with intensified therapy. We must consider carefully this little group of patients in which despite negative i-PET we observe an early progression. These group of patients do not have specific clinical characteristics at diagnosis, probably biological and pathological markers could be associated with i-PET to increase the predictive power and in particular to reduce the false negative or, finally, more sensitive PET evaluation with MTV and GTV evaluation could reduce the false negative i-PET.

Copyright © 2018 The Authors. Published by Wolters Kluwer Health Inc., on behalf of the European Hematology Association.