Positron Emission Tomography With 2-[18F]-Fluoro-2-Deoxy-D-Glucose For Initial Staging Of Hodgkin Lymphoma: A Single Center Experience In Brazil

Abstract

PURPOSE:The aim of the present study was to investigate the effectiveness of FDG-PET in the initial staging of HL patients in a Brazilian population. METHODS: Eighty-two patients with newly diagnosed HL were prospectively included in the study. All patients were staged with both conventional clinical staging (CCS) methods, including computed tomography (CT) and whole-body FDG-PET methods. A standard of reference for the nodal regions and the extranodal organs was determined using all available information, including the CCS methods, FDG-PET, the diagnostic histology and the follow-up examinations. The results of the CCS were then compared to the FDG-PET results. RESULTS:The sensitivity of FDG-PET was higher for nodal staging than that of CT (87.8% vs. 61.6%, respectively). FDG-PET was also more sensitive than CT in regard to evaluating the extranodal organs for lymphomatous involvement (96.2% vs. 40.0%, respectively). FDG-PET detected all 16 patients who were characterized by a positive bone marrow biopsy and identified an additional 4 patients with bone marrow disease. The incorporation of FDG-PET coupled with CCS in the staging procedure upstaged 20% (17/82) of the patients and downstaged 11% (9/82) of the patients. As a result of these changes in staging, 15% (13/82) of the patients would have received a different therapeutic regimen. CONCLUSIONS: The FDG-PET method is superior to CT for the detection of nodal and extra-nodal HL. The observation that the FDG-PET method upstaged the disease was the most common result (20% of patients) brought about by the addition of PET to the staging algorithm, even in a population of patients with a high incidence of advanced disease. However, changes in stages based on FDG-PET results should be confirmed by biopsy.

The diagnostic value of FDG–PET cannot be judged by iliac bone marrow biopsy

“…Current guidelines have made it clear that diffuse uptake in the bone or bone marrow, even if more intense than in the liver, should not be interpreted as BMI [16,17]. Thus, taking diffuse FDG uptake as a positive finding on PET will lead to a lot of false-positive findings on PET and will decrease the positive predictive value (PPV) of FDG-PET.As a result, we cannot agree with the authors' conclusion that FDG-PET/CT had a PPV of 29.72% in detecting BMI, which is totally different from our clinical findings and different from other research reports [7][8][9][10][11][12]14]. Given that the incidence of BMI in Hodgkin's lymphoma is approximately 20-30%, the PPV of 29.72 for FDG-PET/CT, as this paper reported, essentially means that FDG-PET/CT has no diagnostic value for detecting lymphomatous BMI.…”

“…As a result, we cannot agree with the authors' conclusion that FDG-PET/CT had a PPV of 29.72% in detecting BMI, which is totally different from our clinical findings and different from other research reports [7][8][9][10][11][12]14]. Given that the incidence of BMI in Hodgkin's lymphoma is approximately 20-30%, the PPV of 29.72 for FDG-PET/CT, as this paper reported, essentially means that FDG-PET/CT has no diagnostic value for detecting lymphomatous BMI.…”

“…Given that the incidence of BMI in Hodgkin's lymphoma is approximately 20-30%, the PPV of 29.72 for FDG-PET/CT, as this paper reported, essentially means that FDG-PET/CT has no diagnostic value for detecting lymphomatous BMI. This is not consistent with our clinical observation and other research findings, which reported a .90% PPV in a similar clinical setting [7][8][9][10][11][12]. Yours etc., …”

“…The fact that a unilateral iliac BMB missed 26-50% of BMI cases in lymphoma patients (based on the findings of bilateral iliac BMB) [3][4][5][6] provided strong evidence that a significant number of BMI lesions would be missed even if a bilateral iliac BMB was performed. In addition, multiple studies revealed that FDG-PET or PET/CT detects more BMI than iliac BMB [7][8][9][10][11][12]. BMI typically manifests as multifocal FDG abnormalities on FDG-PET imaging [9,10,12].…”

Análise quantitativa do PET-CT ao diagnóstico e interim, como fator prognóstico dos desfechos clínicos de pacientes com linfoma de Hodgkin clássico: experiência de um único centro brasileiro

“…Quase três décadas depois, na conferência de Lugano (2014), nova atualização foi feita e o uso da letra "E" ficou reservado apenas aos estádios I e II (Quadro 2). A tomografia por emissão de pósitrons 18 F-fluoro-2-deoxi-Dglicose (18F-FDG-PET-CT) foi colocada como método preferido para o estadiamento, visto mudar a classificação em 16-31% e estratégia terapêutica em 7-15% dos casos, quando comparado à tomografia computadorizada (TC) 23,24,25 . Foram estabelecidos critérios de avaliação para acometimento hepático, esplênico e de medula óssea, de acordo com o padrão e a intensidade de captação do radiotraçador, ficando dispensada a realização da biópsia de medula óssea, considerando o valor preditivo negativo de 98-99,9% para detecção de envolvimento medular 26,27,28 49 .…”