MicroRNAs as a potential tool in the differential diagnosis of thyroid cancer: a systematic review and meta‐analysis

Summary Objective Thyroid cancer is the most common endocrine malignancy, and its incidence has been increasing over the last 30 years. Several studies have suggested that mi RNA s may play a significant role in the differential diagnosis of indeterminate thyroid nodules. To systematically evaluate the utility of mi RNA s in discriminating malignant thyroid nodules from benign ones on fine‐needle aspiration biopsy ( FNAB ) samples, a systematic review and meta‐analysis of the published literatures were carried out. Patients and Design Three hundred and sixty‐one samples, obtained from 341 patients, were included in the research, and summary sensitivities ( SEN ), specificities ( SPE ), positive likelihood ratios, negative likelihood ratios and diagnostic odds ratio were calculated. Then, summary receiver operating characteristic curves ( SROC s) and areas under the SROC curves ( AUC s) were calculated to further estimate the overall diagnostic value of mi RNA s in thyroid cancer. Results The overall pooled SEN , SPE and AUC are 0·75, 0·81 and 0·89, respectively. For multiple mi RNA s assays, the pooled SEN , SPE and AUC are 0·87, 0·75 and 0·68, respectively. For single mi RNA assays, the corresponding results are 0·71, 0·84 and 0·87, respectively. The corresponding statistical results for differentiating indeterminate FNAB samples are 0·92, 0·68 and 0·86, respectively. Conclusion Our current meta‐analysis suggests that mi RNA s may serve as a novel diagnostic tool in distinguishing malignant thyroid nodules from benign ones on FNAB specimens. In addition, subgroup analysis suggests that a panel of mi RNA s may have a higher sensitivity but a relatively lower specificity than that of single mi RNA in distinguishing thyroid nodules.