The diagnostic value of colour Doppler flow in the peripheral zone of the prostate, with histological correlation

To study the discriminative value of the amount of colour flow on Doppler ultrasound within the peripheral zone of the prostate.

One-hundred and twenty three men were studied using a 7 MHz transrectal probe, and 274 guided biopsies were undertaken. With each biopsy histological outcome was correlated with the grade of colour flow on ultrasound hard copy images. Biopsies with inflammatory cell infiltration, but without carcinoma, were subgraded according to the degree of inflammatory cell infiltration; and these grades were correlated with the corresponding colour flow grade.

Normal colour flow was seen with both normal and abnormal prostate biopsy. With increased colour flow the likelihood of abnormal tissue increases; the highest grade of colour flow was seen with either carcinoma or prostatitis (grade 0, 1, 2 and 3 colour flow = 23%, 65%, 74% and 100% respectively of biopsies that were abnormal). In biopsies with inflammatory cell infiltration there was no linear relationship between the grades of colour flow and cellular infiltration (r = 0.52, P > or = 0.05, Kendall rank correlation). The mean grade of cellular infiltration was significantly greater in samples with grade 3 colour flow compared with grades 0-2.

Grading of the amount of colour flow with Doppler ultrasound is of limited diagnostic discrimination, although with the greatest colour flow specificity for the diagnosis of abnormal prostate (either cancer or prostatitis) is very high. With prostatitis, markedly increased colour flow reflects the severity of inflammatory cellular reaction.