Utility of the PET-CT in the evaluation of early response to treatment in the diffuse large B-cell lymphoma. Preliminary results.

May 2012

[Article in English, Spanish]

Cortés Romera M, Gámez Cenzano C, Caresia Aróztegui AP, Martín-Comín J, González-Barca E, Ricart Brulles Y, Palacios Abufón A, Robles Barba J, Rodríguez-Bel L, Rossi Seoane S, Fernández de Sevilla A.

Source

Unitat PET, Institut de Diagnòstic per la Imatge (IDI), Hospital Universitari de Bellvitge, IDIBELL, L'Hospitalet de Llobregat, Barcelona, España.

Abstract

OBJECTIVE:

To assess the role of FDG-PET/CT performed after the first cycles of chemotherapy in the prediction of response to treatment in patients with diffuse large B-cell lymphoma.

METHODS:

Twenty patients (mean age: 48 years) were included, 16 initial staging and 4 relapse. All patients underwent PET/CT at 3 times: 1) Baseline, 2) After 1-3 cycles of chemotherapy (early response assessment), and 3) End of treatment (evaluation of final response). Early PET/CT findings were correlated to the end-treatment PET/CT and follow-up. The evaluation of the response was established according to the decrease in uptake of the lesions (SUVmax). In the early assessment, a good response indicator (GRI) was obtained when the lesion disappeared or had more than 50% reduction in SUVmax. At the end of the treatment, a complete metabolic response (CMR) was determined in negative PET scans. Follow-up was superior to 19 months and final outcome was established as progression/relapse or no evidence of disease (NED).

RESULTS:

At the early treatment evaluation, 16/16 patients of initial staging (100%) and 2/4 of relapse (50%) achieved GRI. At the end of treatment evaluation, 14/16 patients of initial staging with GRI achieved CMR and 1/16 PMR: 14 were alive with NED in the follow-up while 1 relapsed. In the second group, 2/2 patients with GRI achieved CMR (100%): 1 continued with NED in the follow-up and another relapsed.

CONCLUSION:

 FDG-PET/CT after the first cycles of chemotherapy is useful to monitor treatment due to its high negative predictive value (87.5%), using it to modify treatment early in the non-responders.

Elsevier