[Relationship between peripheral hypoechoic nodules of the prostatic gland and prostate cancer]

The primary objective of the study was to evaluate the incidence of prostate cancer in the hypoechoic nodes located in the periphery of the prostate gland and its relationship with findings by digital rectal examination, and blood PSA and PSAD levels.

Retrospective study of 166 hypoechoic nodes detected and biopsed between January 1994 and August 1995, associating the pathoanatomical results with the findings from digital rectal examination, PSA and PSAD levels. Statistical analysis was done by estimation of confidence intervals for a 95% confidence level.

Nodal cancer was present in 54.8% cases. The association of suspicious rectal examination increased the probability of cancer by 63% (IC95 = 51%-75%). The association of suspicious rectal examination and PSAD > 0.15 increases by 36.7% (IC95 = 11.7%-61.1%) the probability of having cancer versus a suspicious digital rectal examination alone. When no suspicious rectal examination was considered, the difference in the proportions observed for PSA > 10 versus PSA levels > 4 and < or = 10 ng/mL is 13.7% (IC95 = -2.1%-29.4%) and, for PSAD > 0.15 versus PSAD < or = 0.15 was 11.6% (IC96 = 3.8%-27.1%).

Presence of a suspicious rectal examination and PSAD > 0.15 increased significantly the probability of prostate cancer being present in the hypoechoic node. When digital examination is not suspicious, neither the PSA or the PSAD levels influence significantly in the appearance of cancer.