Diffusion-weighted MRI in prostate cancer — comparison between single-shot fast spin echo and echo planar imaging sequences

Diffusion-weighted (DW) MRI at 1.5 T was carried out in two groups of patients. MRI data were correlated with the biopsy and histopathology (where available). The performance of two sequences — a single-shot FSE (14 patients) and a single-shot EPI (15 patients) — was compared. Average ADC values from the normal peripheral zone (PZ), central gland (CG) and the tumour [prostate carcinoma (PCa)] were calculated from b values of 0 and 600. Tukey–Kramer test was used for statistical analysis. EPI produced higher values of ADC (10−3 mm2/s) than FSE sequence: 1.992±0.208 vs. 1.573±0.270 in PZ (P<.001), 1.518±0.126 vs. 1.373±0.179 in CG and 1.214±0.254 vs. 0.993±0.158 in PCa (P<.01). In conclusion, both EPI and FSE sequences showed differences in ADC between normal PZ, CG and PCa; however, EPI produced significantly higher ADC values than FSE.