Published online Feb 7, 2015. doi: 10.3748/wjg.v21.i5.1621
Peer-review started: June 27, 2014
First decision: July 21, 2014
Revised: August 23, 2014
Accepted: September 30, 2014
Article in press: September 30, 2014
Published online: February 7, 2015
AIM: To investigate the diagnostic capability of breath-hold diffusion-weighted imaging (DWI) for differentiation between malignant and benign hepatic lesions.
METHODS: A total of 614 malignant liver lesions (132 hepatocellular carcinomas, 468 metastases and 14 intrahepatic cholangiocarcinomas) and 291 benign liver lesions (102 hemangiomas, 158 cysts, 24 focal nodular hyperplasia, 1 angiomyolipoma and 6 hepatic adenomas) were included from seven studies (eight sets of data).
RESULTS: The pooled sensitivity and specificity of breath-hold DWI were 0.93 [95% confidence interval (CI): 0.91-0.95] and 0.87 (95%CI: 0.83-0.91), respectively. The positive likelihood ratio and negative likelihood ratio were 7.28 (95%CI: 4.51-11.76) and 0.09 (95%CI: 0.05-0.17), respectively. The P value for χ2 heterogeneity for all pooled estimates was < 0.05. From the fitted summary receiver operating characteristic curve, the area under the curve and Q* index were 0.96 and 0.91, respectively. Publication bias was not present (t = 0.49, P = 0.64). The meta-regression analysis indicated that evaluated covariates including magnetic resonance imaging modality, echo time, mean age, maximum b factor, and number of b factors were not sources of heterogeneity (all P > 0.05).
CONCLUSION: Breath-hold DWI is useful for differentiating between malignant and benign hepatic lesions. The diffusion characteristics of benign lesions that mimic malignant ones have rarely been investigated.
Core tip: We investigated the diagnostic capability of breath-hold diffusion-weighted imaging (DWI) and found that it is useful for differentiating between malignant and benign hepatic focal lesions. The diffusion characteristics of the benign liver lesions that mimic malignant lesions have rarely been investigated and further studies are needed. Standardization of the acquisition protocol for breath-hold DWI across multicenter trials is recommended.