Prostate-specific antigen detected prostate cancer: pathological characteristics of ultrasound visible versus ultrasound invisible tumors.

Most studies examining the issue of 'early detection of prostate cancer' advocate the combined use of serum prostate-specific antigen (PSA) and digital rectal examination (DRE). As a result, a significant number of new prostate cancers are diagnosed on the basis of an elevated serum PSA when the DRE is unremarkable. The purpose of this study is to determine if the PSA-detected tumors that are visible on transrectal ultrasound (TRUS) have the same pathological characteristics as PSA-detected tumors that are invisible on TRUS. One hundred and ninety-four patients with an elevated serum PSA concentration and nonpalpable prostate cancer who underwent radical retropubic prostatectomy (RRP) at our institution between March 1988 and December 1991 were reviewed. The patients were divided into two groups: 97 (50%) had no identifiable lesion on TRUS, and 97 (50%) had at least one hypoechoic area consistent with adenocarcinoma of the prostate. The pathological characteristics of the RRP specimens from the two groups were compared. There was no significant difference in the age (p = 0.14) or the preoperative serum PSA values (p = 0.18) between the groups. Also, there was no significant difference between the groups with regard to tumor volume (p = 0.89), focality of the cancer (p = 0.43), Gleason score (p = 0.81), DNA ploidy status (p = 0.96), pathological stage (p = 0.92), surgical margin involvement (p = 0.27), and tumor location (p = 0.64). These findings suggest that the clinical TNM staging system for prostate cancer may be simplified by eliminating the distinction between PSA-detected cancers visible on TRUS and PSA detected cancers not visible on TRUS.(ABSTRACT TRUNCATED AT 250 WORDS)