[The value of positron emission tomography/computed tomography (PET/CT) in the staging of diffuse large B-cell lymphoma].

Background and Objective: The aim of this study was to evaluate the role of positron emission tomography/computed tomography (PET/CT) in improving the staging and changing the management of aggressive lymphoma patients in comparison with the conventional imaging modalities (CT, and 67Ga scintigraphy).
Patients and Method: Forty consecutive patients with diffuse large B-cell non Hodgkin lymphoma, were prospectively evaluated. All 40 patients underwent a whole body FDG PET/CT and conventional staging techniques (chest and abdomen CT, 67Ga scintigraphy) were studied before therapy. Sixty minutes after the intravenous administration of 370 MBq FDG, a whole body PET/CT was acquired. We hypothesize that PET/CT improves the diagnostic staging of lymphoma and changes the clinical management of patients.
Results: PET/CT and CT were concordant in 28 patients (65%). However, PET/CT detected more lesions than CT in 11 patients (27.5%). Only in one patient, CT revealed more extensive disease than PET/CT. Additional information of PET/CT had lead to a change in staging (upstaging) in 6 patients (15%), in turn leading to a change in treatment strategy in 1 patient. PET/CT and 67Ga scintigraphy were concordant in 23 patients (60.5%). PET/CT detected more lesions than 67Ga scintigraphy in 14 patients (42%). PET/CT results changed staging (upstaging) in 4 patients (15%), leading to a change of treatment strategy in one patient.
Conclusions: The impression is that PET/CT detected more lesions than conventional examination, but this rarely translates into changes of staging and treatment strategy in aggressive lymphoma.