Predicting Prostate Biopsy Outcome by Findings at Digital Rectal Examination, Transrectal Ultrasonography, PSA, PSA Density and Free-To-Total PSA Ratio in a Population-Based Screening Setting

Clinical significance of multiparametric MRI and PSA density as predictors of residual tumor (pT0) following radical prostatectomy for T1a-T1b (incidental) prostate cancer

Purpose

The aim of this study was to evaluate predictors of residual tumor and clinical prognosis in T1a-T1b (incidental) prostate cancer by analysis of specimens from men undergoing surgery for benign prostatic hyperplasia.

Materials and methods

We retrospectively reviewed medical records of incidental prostate cancer patients who had undergone radical prostatectomy. Patients whose tumor statuses were further confirmed by prostate biopsy, or who had used androgen deprivation therapy before radical prostatectomy, were excluded. Clinical and pathological parameters were analyzed to evaluate residual tumor and clinical prognosis. We used univariate and multivariate logistic regression analyses, as well as receiver operator characteristics, to predict residual tumor (pT0).

Results

The final analysis included 95 patients. Among these patients, 67 (70.53%) exhibited residual tumor, whereas 28 (29.47%) did not (pT0). Pathology findings showed that 44 (65.67%), 16 (23.88%), and 7 patients (10.45%) exhibited Gleason scores of G6, G7, and ≥G8, respectively. Fifty-seven and 10 patients exhibited pathologic T stages T2 and T3, respectively. Mean follow-up duration was 70.26 (±34.67) months. Biochemical recurrence was observed in 11 patients; none were pT0 patients. Multivariate logistic regression showed that low prostate-specific antigen density after benign prostatic hyperplasia surgery and invisible lesion on multiparametric magnetic resonance imaging were significantly associated with pT0. Additionally, a combination of these factors showed an increase in the diagnostic accuracy of pT0, compared with mpMRI alone (AUC 0.805, 0.767, respectively); this combination showed sensitivity, specificity, and positive predictive values of 71.6%, 89.3%, and 94.1%, respectively.

Conclusion

Our results suggest that patients with incidental prostate cancer who have both prostate-specific antigen density ≤0.08 after benign prostatic hyperplasia surgery as well as invisible cancer lesion on multiparametric magnetic resonance imaging should be considered for active surveillance.

Free to Total Psa Ratio is not a Reliable Predictor of Prostate Biopsy Outcome

Aims and background

The aim of this study was to assess the validity of predictors of prostate biopsy outcome in order to improve their positive predictive value.

Material and methods

The study material consisted of a consecutive series of 410 prostate biopsies performed during 2003. The variables tested as possible predictors were age, findings at palpation (DRE) and ultrasonography (TRUS), total prostate-specific antigen (PSA), and free-to-total prostate-specific antigen (F/T) ratio. The association with biopsy outcome (cancer vs non-cancer) was investigated by univariate and multivariate analysis.

Results

All tested variables showed a statistically significant and independent association with biopsy outcome both in univariate and multivariate analysis. Nevertheless, no variable had good performance as a biopsy indicator: depending on the considered variable, three to nine cancer biopsies would be delayed in order to avoid ten benign biopsies. Using 0.12, 0.15 and 0.20 as the cutoff for F/T would avoid 77.3%, 64.4% and 43.1% of benign biopsies but would delay 54.0%, 35.6% and 21.0% of cancer biopsies, respectively.

Conclusion

Although it may contribute to diagnostic suspicion, F/T should never exclude a biopsy indicated because of suspicion arising from other diagnostic tests.

On the Clinical Usefulness of the Free-to-Total Prostate-Specific Antigen Ratio

The free-to-total prostate-specific antigen ratio (F/T PSA) is associated with the presence of prostate cancer and is thus used as an indicator for suspicion of prostate cancer and as a determinant for biopsy. We reviewed a recent retrospective series of 966 consecutive prostate biopsies where F/T PSA was blindly determined and did not influence biopsy indication. We simulated the association of F/T PSA with biopsy outcome and its impact as a biopsy determinant. When adopting an F/T PSA cutoff of 10%, 13%, 16% or 20% among random sextant biopsies in the 4–10 ng/mL total PSA range, the sensitivity was 15%, 37%, 55% and 72% and the specificity 89%, 80%, 64% and 44%, respectively. Using F/T PSA as a biopsy determinant, from 1.7 to 2.6 cancer biopsies would have been delayed to avoid 10 benign biopsies. As this balance is not acceptable, F/T PSA has no role as a biopsy indicator and its clinical use is questionable.

PSA Doubling Time as a Predictor of the Outcome of Random Prostate Biopsies Prompted by Isolated PSA Elevation in Subjects Referred to an Outpatient Biopsy Facility in a Routine Clinical Scenario

Aim

To assess the validity of PSA doubling time (PSADT) as a predictor of prostate sextant biopsy outcome in patients with PSA levels in the 4–10 ng/mL range.

Material and methods

A consecutive series of 355 sextant biopsies performed during 2001–2007 in subjects with negative digital rectal examination and transrectal ultrasonography was considered. Variables tested as possible predictors were age, total and free/total PSA value, PSA velocity and PSA doubling time. While PSA at time of biopsy and free/total PSA were determined with a standardized method undergoing strict quality control, previous PSA values used to assess velocity/doubling time came from other labs using different assays over widely varying intervals of time. The association with biopsy outcome (cancer vs non-cancer) was investigated by univariate and multivariate analysis.

Results

Apart from free/total PSA ratio, no other studied variable showed a statistically significant and independent association with biopsy outcome, either at univariate or multivariate analysis. No studied variable had a good performance as a biopsy indicator. Depending on the variable considered, 1.17 to 1.97 cancers would be missed to spare 10 benign biopsies.

Conclusion

When based on PSA data determined with different assays over widely varying intervals and in the absence of an underlying protocol for PSA surveillance, PSA velocity and doubling time should never discount a biopsy prompted by total PSA elevation.

Incidental Prostate Cancer Diagnosis During Holmium Laser Enucleation: Assessment of Predictors, Survival, and Disease Progression

OBJECTIVE

To determine the prevalence and predictors of incidental prostate cancer (IPCa) after Holmium laser enucleation of the prostate (HoLEP) and to assess its functional and oncological outcomes.

METHODS

A prospectively maintained database was reviewed for cases with IPCa at the time of HoLEP. Patients with preoperative PCa were excluded. Patients were divided into two groups based on the presence (group I [GI]) or absence of cancer (group II [GII]) in histopathology. Univariate and multivariate logistic regression analyses were performed.

RESULTS

Of 1242 patients, 70 (5.64%) were identified to have IPCa. Prostate size was comparable between both groups. GI patients had significantly higher preoperative prostate-specific antigen (PSA) and total PSA density (tPSAD) compared to cancer-free patients. T1a and T1b adenocarcinomas were detected in 54 (77.1%) and 16 (22.9%) patients, respectively. After a median follow-up of 48 (1-171) months, both groups were comparable in all functional outcomes but the quality of life was significantly better in GII. Patients' age and preoperative tPSAD independently predicted IPCa after HoLEP. A tPSAD cutoff value of 0.092 has a sensitivity and specificity of 0.83 and 0.67, respectively. Seven patients (11.7%) needed adjuvant therapy while other GI patients opted for active surveillance. The Kaplan-Meier analysis demonstrated an overall survival of 72.8% at 5 years and 63.5% at 10 years for patients with PCa.

CONCLUSION

PCa is not uncommonly identified after HoLEP, even in those with negative preoperative biopsies. In older patients, total PSAD could be a predictor using a cutoff <0.1. After HoLEP, active surveillance for low-grade PCa carries good functional and oncological outcomes.

Role of PSA-related variables in improving positive ratio of biopsy of prostate cancer within serum PSA gray zone

OBJECTIVE

The aim of this study was to assess the validity of predictors of prostate biopsy outcome in order to improve their positive predictive value (PPV). The related variables of PSA such as free/total PSA ratio (F/T), complexed/total PSA ratio (C/T), density of PSA (PSAD) were studied to improve early diagnosis for early PCa within serum PSA gray zone.

METHODS

Samples of venous blood were collected early in the morning from 459 patients, aged 50 to 88 years (average 70.5 years old), whose serum T-PSA was between 4 to 10 ng/mL (153 cases of Pca, 306 cases of BPH). Serum T-PSA, F-PSA and C-PSA were determined by ELISA method; prostate volume was measured by transrectal ultrasound, then prostate biopsy was taken for all patients.

RESULTS

Out of f 459 patients, 153 cases of Pca and 306 of BPH were diagnosed by prostate biopsy, whose mean values of T-PSA were 7.2 ± 1.25 ng/mL and 6.8 ± 0.96 ng/mL, respectively (P<0.05), of F/T were 0.117 ± 0.018 and 0.196 ± 0.021 (P<0.01), and of C/T they were 0.890 ± 0.023 and 0.754 ± 0.015 (P<0.01), of PSAD were 0.197 ± 0.023 and 0.106 ± 0.019 (P<0.01). The threshold of F/T>0.16 diagnosed 91 cases of cancer (59.5%), of C/T>0.84 88 cases (57.5%), of PSAD>0.15 94 cases (61.4%), and especially, of F/T>0.16 combined PSAD>0.15 80 cases whose sensitivity, specificity, accuracy, positive predictive values were 52.3%, 76.1%, 68.2%, 52.3%, respectively (P<0.05).

CONCLUSION

There are some defects only in taking T-PSA as a biomarker for the diagnosis of PCa within serum PSA gray zone, and the threshold of F/T>0.16 combined PSAD>0.15 may be a new and significant indicator to provide a better basis for the diagnosis of early PCa.

The ratio of prostate-specific antigen (PSA) to prostate volume (PSA density) as a parameter to improve the detection of prostate carcinoma in PSA values in the range of < 4 ng/mL

BACKGROUND

The objective of this study was to evaluate the prostate specific antigen (PSA) density (PSAD) (the quotient of PSA and prostate volume) compared with the percent free PSA (%fPSA) in different total PSA (tPSA) ranges from 2 ng/mL to 20 ng/mL. Possible cut-off levels depending on the tPSA should be established.

METHODS

In total, 1809 men with no pretreatment of the prostate were enrolled between 1996 and 2004. Total and free PSA were measured with the IMMULITE PSA and Free PSA kits (Diagnostic Products, Los Angeles, CA). Prostate volume was determined by transrectal ultrasound. The diagnostic validity of tPSA, %fPSA, and PSAD was evaluated by receiver operation characteristic (ROC) curve analysis.

RESULTS

The PSAD differed significantly (P < 0.0001) between patients with prostate carcinoma and patients with benign prostatic hyperplasia in all analyzed ranges of tPSA and prostate volume. At the 90% and 95% sensitivity levels and regarding the area under the ROC curve (AUC) within the tPSA range of 2-4 ng/mL, The PSAD was significantly better than tPSA and %fPSA. Within the tPSA range of 4-10 ng/mL, the PSAD did not perform better than %fPSA.

CONCLUSIONS

PSAD showed a better performance than %fPSA at tPSA concentrations < 4 ng/mL for detecting prostate carcinoma, with a significantly larger AUC for PSAD (0.739) compared with %fPSA (0.667). PSAD did not perform better than %fPSA when the tPSA range of 4-10 ng/mL was analyzed. Different PSAD cut-off values of 0.05 at tPSA 2-4 ng/mL, 0.1 at tPSA 4-10 ng/mL, and 0.19 at 10-20 ng/mL were necessary to reach 95% sensitivity.

Effect of growth hormone (GH) and/or testosterone replacement on the prostate in GH-deficient adult patients

The prostate is a target organ of the GH and IGF-I axis because prostate hypertrophy is found in acromegaly, reduced prostate size is found in GH deficiency (GHD) patients, and additionally, IGF-I is reported to be a positive predictor factor of prostate cancer. To investigate whether GH replacement therapy in adult patients with GHD has adverse effects on the prostate, we studied the effect of 12-month GH or GH plus testosterone replacement on prostate pathophysiology in 24 adult patients with GHD (11 euandrogenemic and 13 hypoandrogenemic), compared with 24 age-matched healthy controls. At study entry, GHD patients had lower prostate volume than controls (19.4 +/- 1.7 vs. 24.9 +/- 1.7 ml; P = 0.03). After 12 months of treatment, all hypoandrogenemic patients achieved normal testosterone levels, and prostate volume increased in the patients to the same level as controls (25.0 +/- 1.9 ml). The percentage increase in prostate volume was greater in hypoandrogenemic patients receiving both GH and testosterone replacement (51 +/- 11%) than in those receiving GH replacement alone (15 +/- 3%; P < 0.0009). At baseline, prostate volume was similar in GHD patients below or above 60 yr of age (16.8 +/- 1.3 vs. 23 +/- 3.6 ml; P = 0.08), whereas after treatment it was higher in the latter patients (21.8 +/- 1.2 vs. 29.5 +/- 3.9 ml; P = 0.04). Prostate-specific antigen (PSA) and free PSA did not change, whereas PSA density was significantly reduced after treatment in hypoandrogenemic patients; there was also no change in calcifications, cysts, or nodules. In conclusion, GH replacement restores prostate size to normal in both young and elderly patients, with no increase in prostate abnormalities. Because the simultaneous treatment with GH and testosterone induces an increase of prostate size by 50% of baseline on average, care is suggested in elderly patients with prostate hyperplasia to avoid any risk of prostate symptoms. In these cases, GH replacement might be performed sequentially to reduce the hypertrophic effect of combining GH and testosterone.