Race-specific reference ranges of serum prostate-specific antigen levels in countries with a low incidence of prostate cancer

Clarifying the PSA grey zone: The management of patients with a borderline PSA

INTRODUCTION

Prostate specific antigen is a marker for prostate cancer and a key diagnostic tool, yet when to refer patients with a borderline PSA is currently unclear. This review describes how to assess a patient with borderline PSA and provides an algorithm for management.

METHODS

Current literature on reference values, factors affecting PSA, indications for referral, non-invasive investigations and the role of MRI were reviewed. Medline and EMBASE were searched using MeSH terms.

RESULTS

The literature suggests that a PSA of over 1.5 ng/mL should be used as a cut-off to consider further testing for all age groups. There is strong evidence to show that adjuncts are useful when interpreting PSA results, most notably percentage free PSA and proPSA. Considerable weighting should also be given to the ERSPC risk calculator when deciding when to refer. Multi-parametric MRI is valuable in closely examining suspicious lesions to reduce the number of negative biopsies. MRI fusion biopsy (TRUS, transrectal ultrasonography or transperineal) should be considered over standard TRUS biopsy to detect more clinically significant disease.

CONCLUSIONS

Management of borderline PSA is not straightforward. A cut-off of 1.5 ng/mL should be used in conjunction with digital rectal exam, risk calculation and PSA adjuncts. Imaging and biopsy should utilise mpMRI to achieve improved diagnosis of clinically significant prostate cancer, with fewer unnecessary investigations.

A comparison of prostate cancer detection rates by 12 or 6 core biopsy at different prostate-specific antigen densities in Korean men

OBJECTIVES

To evaluate the diagnostic value of 12 core biopsy versus sextant biopsy at different prostatic-specific antigen densities (PSAD).

METHODS

We retrospectively analyzed the records of 1,463 patients who underwent transrectal ultrasound-guided prostate biopsies at our institution. 995 patients underwent 12 core biopsy and 468 sextant biopsy of the prostate. The cancer detection rates achieved by these two methods were analyzed at different PSAD levels.

RESULTS

All patients were stratified into 5 groups according to PSAD level; group A: PSAD < 0.1 (n = 290), group B: 0.1 < or = PSAD < 0.2 (n = 572), group C: 0.2 < or = PSAD < 0.3 (n = 248), group D: 0.3 < or = PSAD < 0.4 (n = 122), and group E: PSAD > or = 0.4 (n = 231). In group B, 12 core biopsy had a higher detection rate than 6 core biopsy (P = 0.017).

CONCLUSIONS

These results demonstrate 12 core biopsy is better able to detect cancer than 6 core biopsy in patients with a PSAD in the range 0.1-0.2, which suggests that PSAD be considered when deciding on the number of prostate biopsy cores required.

Accuracy of a high prostate-specific antigen level for prostate cancer diagnosis upon initial biopsy in Korean men

PURPOSE

This study aimed to evaluate the cancer detection rate in a Korean population with prostate-specific antigen (PSA) levels greater than or equal to 20.0 ng/mL.

MATERIALS AND METHODS

A total of 174 men 50 to 79 years old (median 69) included in the study. The median prostate volume of the patients was 44.8 mL (range 14.1 to 210.0) and their serum PSA ranged from 20.0 to 9725.0 ng/mL (median 44.8).

RESULTS

Of 174 men 141 (81.0%) were diagnosed with prostate cancer on initial biopsy. In the total number of patients, the positive predictive value (PPV) was 62.9% for PSA 20 to 29.9, 72.7% for PSA 30 to 39.9 and 100% for PSA 40 to 49.9 ng/mL. In patients with an abnormal digital rectal examination (DRE), the values for these PSA ranges increased to 89.5%, 91.7% and 100%, respectively. The PPV was 81.0% for PSA cutoff of 20, 89.2% for a cutoff of 30, 95.4% for a cutoff of 40, and 94.7% for a cutoff of 50 ng/mL. In conjunction with an abnormal DRE, the values for these PSA cutoffs increased to 95.9%, 98.1%, 100%, and 100%, respectively.

CONCLUSION

Our data suggest the ability to predict the presence of prostate cancer reliably on initial biopsy when PSA threshold is greater than or equal to 50 ng/mL. This PSA threshold may be lowered to 40 ng/mL in the presence of an abnormal DRE. In Korean men with high PSA, the detection rate of prostate cancer on biopsy appears to be comparable to that for American men.

Prostate biopsy in subjects with abnormal transrectal ultrasonography but normal digital examination findings and prostate-specific antigen levels

AIM

The aim of the present study was to evaluate the value of transrectal ultrasonography (TRUS) for prostate cancer diagnosis in men with no other indication for biopsy, such as an abnormal digital rectal examination or abnormally high prostate-specific antigen (PSA) levels.

MATERIALS AND METHODS

The study cohort contained a total of 104 men aged 41-78 years (median 62.5 years) who had suspicious findings on TRUS. The median prostate volume of the patients was 33.0 ml (range 15.0-90.9) and the serum PSA ranged from 0.2 to 4.0 ng/ml (median 2.5 ng/ml).

RESULTS

Of 104 men, 12 (11.5%) were diagnosed with prostate cancer on initial biopsy. The positive predictive value (PPV) was 3.7% for PSA 0.1-1.0 ng/ml, 4.8% for PSA 1.1-2.0 ng/ml, 16.7% for PSA 2.1-3.0 ng/ml and 18.4% for PSA 3.1-4.0 ng/ml. The PPV for cancer with Gleason score 7 or higher was 0.0%, 0.0%, 16.7% and 7.9%, respectively. No statistically significant differences in patient characteristics and biopsy results were found between patients who received only systemic biopsy and those who received systemic plus lesion-directed biopsies.

CONCLUSION

The results of this study do not provide a rationale to recommend the additional use of lesion-directed biopsy in patients with suspicious lesions at TRUS but with no other indication for biopsy. Furthermore, our data raise the question of whether serum PSA levels lower than 4.0 ng/ml should be considered normal in Asian men.

Digital rectal examination as a prostate cancer-screening method in a country with a low incidence of prostate cancer

The objective of this study was to evaluate the value of using digital rectal examination (DRE) for prostate cancer diagnosis in an Asian population. Patients with serum prostate-specific antigen (PSA) levels ranging from 2.5 to 19.9 ng/ml underwent transrectal ultrasonography-guided prostate biopsies. Patients were divided into two groups: the normal DRE group (n=721) and the abnormal DRE group (n=192). The cancer detection rate was higher in the abnormal DRE group (47.4%) than in the normal DRE group (23.0%) (P<0.001). However, the detection rates in these two groups were not significantly different in men 45-59 years old as well as in men with low PSA levels (2.5-3.9 ng/ml). In all subjects, the areas under the receiver operating characteristic curves for positive biopsies were 60.0% (95% confidence interval (CI), 55.7-64.3%, P<0.001). However, in the subgroup analysis, the predictive power of the DRE was not significant in men 45-59 years old. In addition, DREs of patients with low PSA levels had no discriminative ability. The pathological features of the prostate biopsies were not significantly different between the two groups in subjects 45-59 years old and in subjects with PSA levels from 2.5 to 3.9 ng/ml. Our data indicate that DREs increase the probability of cancer detection. However, our findings also raise the question, 'Are DREs really useful for cancer detection in younger men and men with low PSA levels in the Asian population?'