Objective:

To compare the correlations of conventional and reduced field-of-view (FOV) apparent diffusion coefficient (ADC) with Gleason score and percentage of tumor involvement in prostate co

re biopsy.

Methods:

A total of 31 patients were confirmed prostate cancer by biopsy after conventional and reduced FOV diffusion weighted imaging (DWI). The cancer visibility on conventional and reduced FOV ADC maps was compared. The ADC value of cancer was measured by the two protocols

and the relationships between ADC value and Gleason score

percentage of tumor involvement were investigated. The relationship between ADC value and Gleason score was further assessed in biopsy samples with different percentages of tumor involvement (10%

11%-40%

41%-70%

71%-100%).

Results:

For 114 positive biopsy sites

cancer visibility on reduced FOV ADC map (100/114) was higher than that on conventional ADC map (86/114) (

P

0.05). Negative correlation between ADC value and Gleason score was observed for whole-sample (

r

=-0.42 and -0.41

P

0.05). There was a negative correlation between ADC value and Gleason score in the samples with 71%-100% of tumor involvement (

r

=-0.62 and -0.56

P

0.05). ADC value was also negatively correlated with percentage of tumor involvement (

r

=-0.69 and -0.63

P

0.05)

and the correlation coefficient was higher than that between ADCvalue and Gleason score.

Conclusion:

Reduced FOV ADC map could improve the visibility of prostate cancer

but ADC value is influenced by Gleason score and percentage of tumor involvement. So ADC value is limited in the prediction of Gleason score.