Gadolinium-based contrast agents are used with magnetic resonance imaging (MRI) to highlight tumor vascularity in organs. They are also widely used for primary tumor visualization. We conducted a systematic review and meta-analysis of the existing evidence of the accuracy of gadolinium-enhanced MRI for staging lymph node metastases.
We systematically searched the MEDLINE, Cochrane, CANCERLIT, and EMBASE databases for studies published in English or German from 1988 年 01 月 1 日, to 2008 年 01 月 1 日, that assessed the diagnostic accuracy of gadolinium-enhanced MRI in the evaluation of lymphatic metastases compared with histopathologic examination as the reference test. Based on a priori-defined clinical considerations, we studied three subgroups of studies: those that used a single malignancy criterion and those that used multiple malignancy criteria with or without contrast highlighting. Summaries of MRI sensitivity and specificity for detecting lymph node metastases were calculated using a bivariate regression model. All statistical tests were two-sided.
The literature search yielded 43 full-text papers that were considered for inclusion in the meta-analysis. We performed quantitative pooled analyses on the 32 studies that provided data on patient-level diagnosis. The weighted estimates of sensitivity and specificity for all studies combined were 0.72 (95+ACU- confidence interval +AFs-CI+AF0- +AD0- 0.66 to 0.79) and 0.87 (95+ACU- CI +AD0- 0.82 to 0.91). Estimates of sensitivity and specificity were essentially unchanged for studies that used a single malignancy criterion (0.71 +AFs-95+ACU- CI +AD0- 0.61 to 0.79+AF0- and 0.88 +AFs-95+ACU- CI +AD0- 0.80 to 0.93+AF0-, respectively+ADs- n +AD0- 11 studies) or multiple malignancy criteria without contrast enhancement (0.70 +AFs-95+ACU- CI +AD0- 0.58 to 0.79+AF0- and 0.86 +AFs-95+ACU- CI +AD0- 0.68 to 0.94+AF0-, respectively+ADs- n +AD0- 6 studies). The sensitivity increased to 0.84 (95+ACU- CI +AD0- 0.70 to 0.92), with a specificity of 0.82 (95+ACU- CI +AD0- 0.72 to 0.89) for the nine studies that incorporated contrast enhancement in their multiple malignancy criteria. Six studies did not define the malignancy criteria they used.
The overall accuracy of gadolinium-enhanced magnetic resonance imaging for the detection of nodal metastases is moderate. Incorporating contrast enhancement in the malignancy criteria substantially improves the accuracy of this diagnostic test.