F-18 FDG PET for evaluation of bone marrow involvement in non-hodgkin lymphoma: A meta-analysis

Background: In recent years, the use of F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has become widespread for the staging of lymphoma. In non-Hodgkin lymphoma (NHL), the bone marrow (BM) involvement is a sign of extensive disease, and the iliac crest BM biopsy (BMB) is the established method for the detection of BM infiltration. However, iliac crest BMB is associated with a high rate of false-negative results. We assess the ability of FDG PET or PET/CT scan to ascertain the presence of BM involvement in aggressive and indolent NHL. Methods: The authors conducted a systematic MEDLINE search of articles published (last update, May 2010). Two reviewers independently assessed the methodological quality of each study. A meta-analysis of the reported sensitivity and specificity of each study was performed. Results: Eight studies met the inclusion criteria. The studies had several design deficiencies. Pooled sensitivity and specificity for the detection of non-Hodgkin aggressive lymphoma were 0.74 (95% CI, 0.65-0.83) and 0.84 (95% CI, 0.80-0.89), respectively. Pooled sensitivity and specificity for the detection of non-Hodgkin indolent lymphoma were 0.46 (95% CI, 0.33-0.59) and 0.93 (95% CI, 0.88-0.98), respectively. Conclusions: The diagnostic accuracy of FDG PET or PET/CT scans was slightly higher but without significant statistical difference (P = 0.1507) in patients with non-Hodgkin aggressive lymphoma as compared with those with non-Hodgkin indolent lymphoma. The sensitivity to detect indolent lymphoma BM infiltration was low for FDG PET or PET/CT.