FDG-PET in the detection of bone marrow disease in Hodgkin's disease and aggressive non-Hodgkin's lymphoma and its impact on clinical management.

AIM: Identification of bone marrow disease (BMD) is a crucial step in the diagnostic work-up of patients with lymphoma. In lymphoma staging, bone marrow biopsy (BMb) is considered as the gold standard, despite its limitations. The aim of this study was to compare the usefulness of 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography (FDG-PET) vs BMb in the detection of BMD in patients with Hodgkin's disease (HL) or aggressive non-Hodgkin's lymphoma (NHL) and its impact on therapy.

METHODS: A total of 194 consecutive patients with malignant lymphoma were referred for staging. The clinical stage was defined according to the Ann Arbor classification by means of contrast enhanced computed tomography (CT), BMb and whole body FDG-PET/CT scan. Sensitivity, specificity, accuracy in BMD evaluation were calculated for PET and BMb.

RESULTS: FDG-PET vs BMb: sensitivity 65.3% vs 55.1%; specificity 98.6% vs 100%; accuracy 90.2% vs 88.7%; positive and negative predictive value 94.1% and 89.3% vs 100% and 86.8%, respectively. Although PET and BMb had similar sensitivity and accuracy, BMD was identified by both methods in only 10 out of 49 patients. There were no significant differences in PET and BMb accuracy between the HL and the NHL patients. Moreover, treatment regimen was changed in 12 patients on the basis of FDG-PET findings.

CONCLUSION: Our study demonstrates that BMb and FDG-PET are complementary in the evaluation of BMD. FDG-PET improves the sensitivity of BMb, especially in the presence of focal BMD. Performing FDG-PET before BMb is advised for optimal biopsy site targeting.