Utility of PET/CT in the Diagnosis and Staging of Extranodal Natural Killer/T-Cell Lymphoma

The role of 18 F-fuorodexoyglucose-positron emission tomography/computed tomography ( 18 F-FDG-PET/CT) in the staging of Hodgkin lymphoma (HL) and aggressive B-cell non-Hodgkin lymphomas (NHL) has been demonstrated extensively. Nevertheless, the role of PET/CT in the diagnosis, staging, prognosis, and treatment evaluation of natural killer (NK)/T-cell lymphoma remains indeterminate. To systematically review and meta-analyze the publications on the value of 18 F-FDG-PET/CT in the diagnosis and staging of NK/T-cell lymphoma. Pubmed, Embase, Cochrane Library, and some other database were searched for initial studies (last updated on May 8th, 2014). The eligibility criteria were studies assessing the usefulness of PET/CT in the staging of NK/T-cell lymphoma, patients were diagnosed as NK/T-cell lymphoma through pathology, or clinical and imaging follow-up. Sensitivities and specificities of 18 F-FDG-PET/CT in individual studies were assessed. The summary receiver operating characteristic curve (sROC) and the area under the curve (AUC) were calculated. The “Meta-Disc 1.4” software was used for data analysis. Eight studies, with a total of 135 NK/T-cell lymphoma patients, were included in this meta-analysis. In terms of the 6 studies with patient based data, the pooled sensitivity and specificity of PET/CT in the diagnosis of NK/T-cell lymphoma were 0.95 (95% CI: 0.89–0.98) and 0.40 (95% CI: 0.09–0.78), respectively. For lesion-based analysis, with 1546 lesions included, the pooled sensitivity and specificity of PET/CT in the staging of NK/T-cell lymphoma were 0.98 (95% CI: 0.96–0.99) and 0.99 (95% CI: 0.99–1.00), respectively. For the patient based data, the AUC and ∗ Q index were 0.8537 and 0.7847, respectively. For lesion based data, the AUC and ∗ Q index were 0.9959 and 0.9755, respectively. The results of this current meta-analysis indicated that PET/CT could be used as a valuable diagnostic and staging tool for NK/T-cell lymphoma.