[Comparative diagnostic value of ultrasonics and rectal examination in prostatic cancer in a series of 213 patients].

The value of endorectal sonography for the diagnosis of prostatic cancer was established after retrospective interpretation of sonographic data issued from 213 patients without prior knowledge of either clinical or pathological data. Endorectal sonography was performed with a mechanical sectorial high frequency (7.5 MHz) probe realized by the authors. A pathology report (73 biopsies, 52 TUR, 7 suprapubic adenomectomy specimens) was available for 132 patients: 25 pathological examinations were interpreted as normal, 41 adenomas, 24 prostatitis or fibrosis and 42 cancers (5 clinical stage T0, 22 T1, 2 T2 and 13 T3). Specificity for the diagnosis of cancer was respectively 65% or 79% according to the normality reference considered, i.e. either the group of patients having a normal pathological control (90 patients) or the same group plus another group of patients with a normal rectal examination (171 patients). Sensitivity for the diagnosis of cancer was only 48%: 53% of cancers were falsely interpreted as prostatitis or adenomas and 9% as normal (2 T0 and 2 T1). The large proportion of local stages without capsular involvement (29/42) is partly responsible for this lack of sensitivity. Sonography can reveal the presence of abnormalities in the echostructure of the gland but does not allow tissue characterization. Rectal examination and sonography are complementary techniques. In the same study, rectal examination had a 48% specificity and a 92% sensitivity.