18F-FDG PET/CT versus bone marrow biopsy in detecting bone marrow infiltration in initial staging of pediatric lymphoma

To evaluate the efficacy of PET/CT using18F-FDG (18F-fluorodeoxyglucose) as a radiotracer compared to conventional bone marrow biopsy (BMB) in detecting infiltration to bone marrow (BM) in pediatric patients with lymphoma at the time of initial diagnosis. 66 pediatric patients with lymphoma (47Hodgkin’s and 19non-Hodgkin’s lymphoma) were referred for initial staging by18F-FDG PET/CT study. All patients underwent bilateral iliac BMB and 18F-FDG PET/CT scan with no more than 2 weeks interval in-between. Follow-up for at least 6 months was used as a reference standard to compare diagnostic performance between two modalities in detecting bone marrow infiltration (BMI). Sensitivity, specificity, accuracy, as well as positive and negative predictive values of 18F-FDG PET/CT in detecting BMI were (80%, 86%, 85%, 63%, and 94%) in contrast to BMB (80%, 53%, 59%, 33%, and 90%) respectively. 18F-FDG PET/CT was concordant to BMB in 39/66 patients (59%). 18F-FDG PET/CT was more accurate and specific, with higher predictive values than BMB in detecting BMI during initial staging of pediatric lymphoma. In most pediatric lymphoma patients, 18F-FDG PET/CT can be used instead of BMB to determine BMI during their initial staging process.