Role of 18F-fluorodeoxyglucose PET/computed tomography in the diagnosis and treatment response assessment of primary bone lymphoma.

OBJECTIVE: Primary bone lymphoma (PBL) is a rare type of extranodal lymphoma, and the clinical application value of 18F-fluorodeoxyglucose PET/computed tomography (18F-FDG PET/CT) in PBL has not been fully evaluated. This study aimed to determine the imaging characteristics of PBL and investigate the value of 18F-FDG PET/CT parameters.

METHODS: A total of 25 patients with PBL who underwent PET/CT examination before treatment were included in this study. The clinicopathological parameters and PET/CT parameters were analyzed.

RESULTS: Among the 25 patients, 7 patients had single lesions, 15 patients had nonsingle lesions (≥2) and 3 patients had diffuse distribution in the medullary cavity. The bone destruction types included osteolytic, osteogenic, normal density, mixed lytic and osteogenic. All patients showed increased FDG uptake, and the CT detection rate was 88%. Five patients underwent PET/CT assessment mid-treatment, and when assessed using the Deauville five-point scale, four patients were PET-negative and one patient was PET-positive. There were two PET-positive and three PET-negative patients when assessed using the Δ maximum standardized uptake value (SUVmax) method. Six patients underwent PET/CT imaging at the end of treatment. When assessed using the Deauville five-point scale, five patients (83%) were PET-negative and one patient (17%) was PET-positive. The same results were obtained when evaluated by the ΔSUVmax method.

CONCLUSION: PET/CT plays a substantial role in the diagnosis and treatment efficacy evaluation of PBL, and it should be recognized by clinicians and radiologists. Changes in metabolic parameters such as SUV, metabolic tumor volume and total lesion glycolysis have considerable potential for application in PBL diagnostics and treatment efficacy evaluation.