Published online May 28, 2015. doi: 10.3748/wjg.v21.i20.6374
Peer-review started: October 17, 2014
First decision: October 29, 2014
Revised: November 26, 2014
Accepted: December 19, 2014
Article in press: January 5, 2015
Published online: May 28, 2015
Processing time: 232 Days and 4.5 Hours
AIM: To investigate the diagnostic ability of single-shot echo-planar imaging (EPI) diffusion-weighted imaging (DWI) to differentiate between malignant and benign pancreatic lesions.
METHODS: A computerized search was performed on PubMed, MEDLINE and EMBASE up to August 2014. Nine studies (10 sets of data) with a total of 304 malignant pancreatic lesions and 188 benign pancreatic lesions were included. The characteristics of each study included the study name, year of publication, magnetic resonance modalities used, patient population, strength of field, pulse time, repetition time, echo time (TE), maximum b factor, mean age, mean body weight, fat suppression, number of benign and malignant lesions, and true positive, true negative, false positive and false negative results. All analyses were performed using Meta-DiSc and Stata 11.0.
RESULTS: The pooled sensitivity and specificity of single-shot EPI DWI were 0.83 (95%CI: 0.79-0.87) and 0.77 (95%CI: 0.70-0.83), respectively. The positive likelihood ratio and negative likelihood ratio were 5.09 (95%CI: 2.19-11.84) and 0.23 (95%CI: 0.15-0.36), respectively. The P value for the 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 0.89 and 0.82, respectively. Publication bias was not present (t = 0.58, P = 0.58). Meta-regression analysis indicated that fat suppression, mean age, TE, and maximum b factor were not sources of heterogeneity (all P > 0.05).
CONCLUSION: Single-shot EPI DWI is useful to differentiate between malignant and benign pancreatic lesions. Lesion size ≥ 2 cm is the limit for the diagnosis of early lesions.
Core tip: We performed a meta-analysis to investigate the diagnostic capability of single-shot echo-planar imaging (EPI) diffusion-weighted imaging (DWI) to differentiate between malignant and benign pancreatic lesions. Single-shot EPI DWI was useful to differentiate between malignant and benign pancreatic lesions. Lesion size ≥ 2 cm was the limit for the diagnosis of early lesions.