Value of using real time elastography for detection of prostate cancer in men with PSA between 2.5 and 10 ng / ml versus systematic prostate biopsy with digital rectal examination and rectal ultrasound prostate trans-negative: no impact on the cancer detection rate
INTRODUCTION AND OBJECTIVES: The gold standard approach in the diagnosis of prostate cancer (PC) includes the serum prostate specific antigen (PSA) value, the digital rectal examination (DRE) and the ultrasound-guided systematic prostate biopsy sampling. Although over the years has tried to increase the sensitivity and specificity of this approach, the detection rate remains poor. New imaging modalities capable of displaying PC represent the subject of intensive research. Real Time Elastography (RTE) has been proposed as a new device to increase the detection rate of PC and reduce the number of biopsies for patient. Here we prospectively assess the real impact of RTE towards the detection rate of PC compared to systematic biopsy with 13 cores in patients with PSA between 2.5 ng/ml and 10 ng/ml with trans-rectal ultrasound and DRE negative.
Methods and results
METHODS: The study included 102 patients with a mean age of 64.5 years, a median PSA of 5.92 ng/ml, a median prostate volume 45 ml and a ratio free-to total ratio median of 16%. All patients underwent trans-rectal ultrasound. In addition, they performed a double-blind assessment of RTE performed by two experienced sonographers. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy have been estimated for each patient and for each biopsy-core.
RESULTS: A total of 32/102 (31.3%) patients were found positive for PC at the biopsy analysis. In 30/102 (29.4%) patients RTE revealed areas of greatest stiffness suspected of malignancy. The true positives were 7/102 patients (6.8%). PC was present in areas highlighted by RTE as well as in normal prostatic tissues. The false negatives were 22/102 (21.6%) patients. The RTE sensitivity, specificity, positive predictive value and negative predictive value were 24.4%, 65.7%, 21.9%, 68.6%, respectively. The accuracy was 53.9%. Considering the patients with suspected cores at RTE, we found 60 positive cores including PC in 9 (15%) cores. When considered the systematic biopsy cores we analyzed 1326 of which positive for PC 103 (7.76%).
CONCLUSIONS: The use of Real Time Elastography (RTE) needs a trainee in spite of expert urologists in the field of ultrasound and biopsy procedures . In addition , Real Time Elastography (RTE) is time – consuming . Only 1 out of 102 patients result true positive . In other 6 patients Real Time Elastography (RTE) reported areas positive for prostate cancer (PC), although neoplastic foci were histologically found also in areas suggested by Real Time Elastography (RTE) as apparently negative . Further studies are necessary to define the helpfulness of Real Time Elastography (RTE) in the detection of prostate cancer (PC) .Argomenti: cancro della prostata