PROSTATE SPECIFIC ANTIGEN ADJUSTED FOR TRANSITION ZONE EPITHELIAL VOLUME: THE POWERFUL PREDICTOR FOR THE DETECTION OF PROSTATE CANCER ON REPEAT BIOPSY

Significance of the prostate central gland and total gland volume ratio in the diagnosis of prostate cancer patients in the prostate specific antigen grey zone

Objective

To explore the significance of the prostate central gland to total gland volume ratio (PVc/PV) in the diagnosis of prostate cancer (PCa) in patients with prostate specific antigen (PSA) levels in the grey zone (4–10 ng/ml).

Methods

This retrospective study enrolled patients that had undergone prostate biopsy. The volume of the prostate and the central prostate gland were measured. The differences in PSA, the ratio of free to total PSA (f/tPSA), PSA density (PSAD) and PVc/PV between the PCa and non-PCa groups were compared. Receiver operating characteristic curve analysis for PCa and clinically significant PCa (csPCa) diagnosis were calculated according to PSA (reference), f/tPSA, PSAD and PVc/PV.

Results

This study enrolled 136 patients. There was no significant difference in PSA and f/tPSA between the PCa and non-PCa groups, while there were significant differences in PSAD and PVc/PV. The area under the curve values of PVc/PV for PCa or csPCa diagnosis were 0.876 and 0.933, respectively; and for PSAD, they were 0.705 and 0.790, respectively. These were significantly different compared with the PSA curve, whereas f/tPSA showed no significant difference from the PSA curve.

Conclusion

PVc/PV could be a predictor of PCa when PSA is between 4–10 ng/ml.

Peripheral zone prostate-specific antigen density: an effective parameter for prostate cancer prediction in men receiving 5α-reductase inhibitors

Purpose:

To evaluate the predictive performance of various parameters derived from volume-adjusted prostate-specific antigen (PSA) values in detecting prostate cancer (PCa) and high-grade (Gleason score≥7) PCa according to treatment with a 5α-reductase inhibitor (5ARI).

Methods:

The results of 3,520 prostate biopsies performed between May 2006 and January 2013 were retrospectively assessed. With adjustment for age, 291 patients who had received 5ARI treatment for more than 6 months were identified and matched 1:3 to patients naïve to 5ARIs, resulting in a total of 873 patients. Peripheral zone (PZ) and transition zone (TZ) volumes were determined by transrectal ultrasonography. Receiver-operating characteristic (ROC) curve analysis was used to compare predictive performances of PSA, PSA density (PSAD; PSA/prostate volume), PZPSAD (PSA/PZ volume), and TZPSAD (PSA/TZ volume) for detecting PCa and high-grade PCa for each group.

Results:

The area under the ROC curve (AUC) was higher for PSAD than for PSA in the 5ARI group (0.751 vs. 0.677) and in the 5ARI-naïve group (0.649 vs. 0.582), respectively (P<0.001). In the 5ARI group, the AUC for PZPSAD was even higher than that for PSAD (0.781 vs. 0.751, P=0.038); in the 5ARI-naïve group, however, PZPSAD failed to achieve significant superiority (0.652 vs. 0.649, P=0.321). All volume-adjusted PSA indexes showed higher predictive accuracies for detecting PCa than did PSA in both groups. For detecting high-grade cancer, PZPSAD also revealed the highest predictive value in the 5ARI group, whereas PSA revealed the highest predictive value in the 5ARI-naïve group.

Conclusions:

The diagnostic performance of PSAD in the detection of PCa is superior to that of PSA. For patients receiving 5ARI for more than 6 months, PZPSAD confers additional benefits for detecting both PCa and high-grade PCa.

Between-subject variations of transition zone epithelial volume and serum PSA levels in men with benign prostatic hyperplasia

PURPOSE

We verified if the measure of transition zone epithelial volume (TZepiV) could be a valid predictor of serum PSA value in men with benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

Between January 2005 and July 2008, a total of 90 patients undergoing transvesical suprapubic adenomectomy for sintomatic BPH were enrolled. In case of an elevated PSA level (above 4 ng/ml) or abnormal digital rectal examination, systematic multisite biopsies were performed preoperatively to rule out prostate cancer. We have examined PSA levels before and after open surgery, TZ weight as measured by the pathologist and TZepiV by multiplying percentage of epithelium of a single biopsy core with the weight of adenoma. Means, Spearman correlation coefficients and percent change were calculated for all variables and intervals.

RESULTS

The mean serum PSA decreased from 4.8 ng/ml preoperatively to 0.5 ng/ml postoperatively. The mean decrease in PSA was 90% (range 70-99%).The mean weight of enucleated adenoma was 67 gr.(range 18-201) and the TZepiV was 7.7 ml (0.3-28.4). Overall, both TZ volume and TZepiV were correlated to PSA value with TZepiV representing the most predictive variable for PSA (r = 0.54 P = 0.002 vs. r = 0.26 P = 0.02). When we analyzed different ranges of PSA values, only TZepiV was always significantly proportional to PSA.

CONCLUSIONS

Ninety percentage of serum PSA level comes from TZ in range of 0.01-0.17 ng/ml/gr. In presence of equal BPH volumes, the amount of epithelium can be different and it is the main determinant in PSA increase. Thus, TZ epithelial volume could represent a new useful clinical tool able to increase the specificity of PSA in the diagnosis of prostate cancer.

Making Sense of Prostate Specific Antigen: Improving its Predictive Value in Patients Undergoing Prostate Biopsy

PURPOSE

The clinical usefulness of PSA for prostate cancer screening is unclear, although the test remains in common use. New methods to interpret PSA are needed.

MATERIALS AND METHODS

We examined a cohort of 2,637 men who underwent prostate biopsies for abnormal DRE or PSA between 1999 and 2004. Using risk factors for prostate cancer, including patient age, ethnicity, family history of prostate cancer, previous negative biopsy, voiding symptoms and prostate volume, we developed risk groups for prostate cancer using recursive partitioning modeling independent of PSA or DRE. We then compared prostate cancer probabilities by PSA ranges by risk group.

RESULTS

Of the 2,637 men 1,282 (48.6%) had prostate cancer. Age, ethnicity, family history, previous negative biopsy and prostate volume were predictive for cancer. We constructed 6 risk groups by combining these factors and created tables to assign patients to these groups. Independent of PSA and DRE the probability of cancer ranged from 15% in patients in group 1 to 78% in patients in group 6 (p <0.0001). By adding PSA and DRE to each risk group prostate cancer probabilities were refined from 0% to 100%. Patients in the higher risk groups also had higher grade cancer (p <0.0001).

CONCLUSIONS

We generated 6 risk groups based on simple risk factors for prostate cancer. When used in the right context and patient, PSA is highly accurate for predicting prostate cancer and permitting rational decision making in patients with abnormal PSA.