EUS for locoregional staging of prostate cancer--a pilot study

This was a pilot study on EUS for locoregional evaluation of prostate cancer.

Our purpose was to evaluate radial and linear-array EUS in locoregional prostate cancer staging.

From April to December 2005, 23 patients were referred to the Department of Urology with a confirmed or highly suspected diagnosis of prostate cancer on the basis of cytohistologic examination of fragments obtained by transrectal US-guided biopsy or transuretheral means. After institutional review board approval, informed consent was obtained from all patients.

An endosonographer and a radiologist with expertise in prostate imaging performed radial and linear EUS examinations without knowledge of the stage of prostate cancer of the referred patients.

Systematic prostatic evaluation by EUS. All patients underwent prostatectomy, and the surgical specimens were analyzed and correlated with EUS findings.

Mean age was 65.91 years, and the mean prostate-specific antigen level was 27.73 ng/mL. Histopathologic study of the surgical specimen revealed adenocarcinoma in 20 of 23, atypical adenomatous hyperplasia in 2 of 23, and sclerosing adenosis in 1 of 23. Staging by EUS for T stage showed different sensitivity (S), specificity (E), and accuracy (A) according to the degree of tumor invasiveness as follows: T1 (S: 51.3%, E: 53.2%, A: 49.1%); T2 (S: 100%, E: 91.67%, A: 95%); T3 (S: 100%, E: 100%, A: 100%). In 3 (3/23) patients EUS did not find a defined lesion, but the surgical specimen showed T1 stage cancer. EUS staging for N stage showed 62.5% sensitivity, 58.33% specificity, and 60% accuracy for N0. Regarding N1, 58.3% sensitivity, 52.50% specificity, and 60% accuracy were found.

Uncontrolled, nonrandomized study.

EUS presented high sensitivity, specificity, and accuracy for prostate cancer staging.