Association of quantitative magnetic resonance imaging parameters with histological findings from MRI/ultrasound fusion prostate biopsy.

INTRODUCTION: Purpose of this pilot study was to correlate quantitative parameters derived from the multiparametric magnetic resonance imaging (MP-MRI) of the prostate with results from MRI guided transrectal ultrasound (MRI/TRUS) fusion prostate biopsy in men with suspected prostate cancer. MATERIALS AND METHODS: Thirty-nine consecutive patients who had 3.0T MP-MRI and subsequent MRI/TRUS fusion prostate biopsy were included and 73 MRI-identified targets were sampled by 177 cores. The pre-biopsy MP-MRI consisted of T2-weighted, diffusion weighted (DWI), and dynamic contrast enhanced (DCE) images. The association of quantitative MRI measurements with biopsy histopathology findings was assessed by Mann-Whitney U- test and Kruskal-Wallis test. RESULTS: Of 73 targets, biopsy showed benign prostate tissue in 46 (63%), cancer in 23 (31.5%), and atypia/high grade prostatic intraepithelial neoplasia in four (5.5%) targets. The median volume of cancer-positive targets was 1.3 cm3. The cancer-positive targets were located in the peripheral zone (56.5%), transition zone (39.1%), and seminal vesicle (4.3%). Nine of 23 (39.1%) cancer-positive targets were higher grade cancer (Gleason grade > 6). Higher grade targets and cancer-positive targets compared to benign lesions exhibited lower mean apparent diffusion coefficient (ADC) value (952.7 < 1167.9 < 1278.9), and lower minimal extracellular volume fraction (ECF) (0.13 < 0.185 < 0.213), respectively. The difference in parameters was more pronounced between higher grade cancer and benign lesions. CONCLUSIONS: Our findings from a pilot study indicate that quantitative MRI parameters can predict malignant histology on MRI/TRUS fusion prostate biopsy, which is a valuable technique to ensure adequate sampling of MRI-visible suspicious lesions under TRUS guidance and may impact patient management. The DWI-based quantitative measurement exhibits a stronger association with biopsy findings than the other MRI parameters.

Prostate volumetric assessment by magnetic resonance imaging and transrectal ultrasound: impact of variation in calculated prostate-specific antigen density on patient eligibility for active surveillance program.

OBJECTIVE: The objective of this study was to investigate impact of prostate volume variations on prostate-specific antigen density (PSAD) and patient eligibility for active surveillance (AS). METHODS: Prostate volume and PSAD were calculated for 46 patients with prostate cancer in AS who underwent prostate magnetic resonance imaging and transrectal ultrasound (TRUS). Manual method and 2 semiautomated methods for prostate segmentation (3D-SLICER and OsiriX) were used for MR volumetry. RESULTS: Magnetic resonance volumetric methods showed very good agreement (intraclass correlation coefficient, 0.98). The concordance correlation coefficient was higher among MR volumetry methods (0.971-0.998) than between TRUS and MR volumetry (0.849-0.863). The variation in PSAD estimated by TRUS versus magnetic resonance imaging was higher in large prostates (r = 0.327, P = 0.027). Transrectal ultrasonography volumetry may improperly classify 20% of patients as eligible for AS with PSAD greater than 0.15 threshold. CONCLUSIONS: Although clinically used TRUS reliably estimates PSAD, it may misclassify some patients who are not eligible for AS based on PSAD criteria. Magnetic resonance-based volumetry should be considered for a more reliable PSAD calculation.

Testosterone in prostate cancer: the Bethesda consensus.

OBJECTIVE: • Androgen stimulation of prostate cancer (PCa) cells has been extensively studied. The increasing trend of using serum testosterone as an absolute surrogate for castration state means that the diagnostic measurement of testosterone and the values potentially influencing prognosis must be better understood. This is especially important when PCa progresses from an endocrine to an intracrine status. PATIENTS AND METHODS: • We performed a literature review using the MEDLINE database for publications on: (i) hormonal changes with androgen deprivation therapy (ADT); (ii) monitoring hormonal therapy with testosterone measurement; (iii) the efficacy of intermittent androgen deprivation (IAD) compared with continuous androgen deprivation; (iv) the underlying mechanisms of castration-resistance; and (v) novel treatments for castration-resistant PCa (CRPCa). RESULTS: • The optimum serum castration levels to be achieved with ADT are still debated. Recently, the 50 ng/dL threshold has been questioned because of reports indicating worse outcomes when levels between 20 and 50 ng/dL were studied. Instead, a 20 ng/dL threshold for serum testosterone after ADT in patients with advanced prostate cancer was recommended. CONCLUSION: • Understanding the mechanisms of androgen biosynthesis relating to PCa as well as prognostic implications might achieve a consensus regarding the role of ADT for both the androgen-sensitive and -insensitive disease state.

An algorithm for medical management in male lower urinary tract symptoms.

PURPOSE OF REVIEW: Benign prostatic hyperplasia (BPH) as the main cause of lower urinary tract symptoms (LUTS) may lead to acute urinary retention and need for BPH-related surgery. The present article describes the result of the recent trials on different medical treatment options. RECENT FINDINGS: Recent studies have shown the efficacy of new selective α-blockers (silodosin and naftopidil); however, there are limited data and no strong evidence for the use of these new agents. Combination therapy of α-blocker and 5α-reductase inhibitor results in great benefit for symptom improvement as well as risk reduction of disease progression and complications. The use of selective antimuscarinic agents in patients with moderate-to-severe symptoms and nonobstructive pattern recognized as overactive bladder type has also been successfully evaluated. There is also a potential clinical use of phosphodiesterase type 5 inhibitors in patients with coexisting LUTS and erectile dysfunction. SUMMARY: Initial evaluation and filling appropriate questionnaires of the disease severity and quality are important steps in medical management of LUTS. Other comorbidities including erectile dysfunction, cardiovascular diseases should also be evaluated. Using prostate volume, uroflowmetry, serum PSA, one could estimate the risk of clinical progression. Most patients benefit from combination therapy of α-blocker and 5α-reductase inhibitor.

Magnetic resonance-invisible versus magnetic resonance-visible prostate cancer in active surveillance: a preliminary report on disease outcomes.

OBJECTIVE: To assess the association between magnetic resonance (MR) appearance of prostate cancer on a baseline multiparametric prostate (MP) MR imaging (MRI) and biopsy outcome in men with favorable-risk prostate cancer managed with active surveillance (AS). MATERIALS AND METHODS: Ninety-six consecutive men (mean age, 67.8 years) who had a baseline MP MRI within 1 year of AS enrollment were included in the study. MP MRI results were analyzed to identify men with MR-invisible tumor defined as no signal abnormality on T2-weighted images, no focal restricted diffusion, and no perfusion abnormality on dynamic contrast-enhanced images. Patients with (n = 84) or without (n = 12) MR-visible tumor were compared and the impact of MR-invisibility of tumor on the risk of adverse biopsy pathology based on the Epstein criteria was investigated with a median follow-up of 23 months. RESULTS: Adverse biopsy pathology occurred in 36.5% (35 of 96) of patients. There was no significant difference in the fulfillment of AS criteria at enrollment, prostate-specific antigen level or density, prostate volume, and number of biopsies (total or after MRI) between the 2 groups of patients. A total of 8.3% (1 of 12) of men with MR-invisible tumor had adverse biopsy pathology as compared with 40.5% (34 of 84) of men with MR-visible tumors. The MR-invisibility of tumor was associated with a lower risk of adverse biopsy pathology (crude relative risk = 0.35; 95% confidence interval, 0.10-1.25; prostate-specific antigen density-adjusted relative risk = 0.21; 95% confidence interval, 0.03-1.32). CONCLUSION: The MR-invisibility of tumor on MP MRI could be of prognostic significance in monitoring men in AS with potential benefit of tailoring the frequency of surveillance biopsies and reducing the number of unnecessary biopsies.

Performance of multiparametric magnetic resonance imaging in the evaluation and management of clinically low-risk prostate cancer.

OBJECTIVE: The purpose of this article is to review the multiparametric magnetic resonance imaging (mMRI) of the prostate and MR-guided prostate biopsy, and their role in the evaluation and management of men with low-risk prostate cancer. METHODS: We performed a literature review based on the MEDLINE database search for publications on the role of mMRI (a) in detection and localization of prostate cancer, prediction of tumor aggressiveness and progression and (b) in guiding targeted prostate biopsy. RESULTS: The mMRI, particularly diffusion-weighted imaging with T2-weighted imaging, is a useful tool for tumor localization in low-risk prostate cancer as it can detect lesions that are more likely missed on extended biopsy schemes and can identify clinically significant disease requiring definitive treatment. The MR-guided biopsy of the most suspicious lesions enables more accurate and safer approach to guide enrollment into the active surveillance program. However, the MR-guided biopsy is complex. The fusion of MRI data with transrectal ultrasound for the purpose of biopsy provides a more feasible technique with documented accurate sampling. CONCLUSION: Although the mMRI is not routinely used for risk stratification and prognostic assessment in prostate cancer, it can provide valuable information to guide management of men with low-risk disease. Incorporation of mMRI into the workup and monitoring of patients with low-risk prostate cancer can help discriminate clinically significant disease from indolent disease. Targeted biopsy of MR-suspicious lesions enables accurate sampling of potentially aggressive tumors that may affect outcomes.

Effect of combination treatment on patient-related outcome measures in benign prostatic hyperplasia: clinical utility of dutasteride and tamsulosin.

BACKGROUND: Benign prostatic hyperplasia, the fourth most commonly diagnosed medical condition in the elderly, is a major underlying cause of lower urinary tract symptoms in men. Medical therapy is usually the first therapeutic option. Combination therapy is increasingly used for better symptom relief and outcome. METHODS: We searched the literature using the MEDLINE database for the efficacy of combination therapy in men with benign prostatic hyperplasia in terms of symptom improvement and impact on quality of life. RESULTS: Combination therapy with dutasteride and tamsulosin not only provides better symptom improvement and improved urinary flow rate, but is also associated with a more favorable impact on quality of life and patient satisfaction with treatment than monotherapy. Combination therapy also reduces the risk of events related to disease progression, such as acute urinary retention and benign prostatic hyperplasia-related surgery. CONCLUSION: Combination therapy with dutasteride and tamsulosin is highly efficacious as medical therapy for benign prostatic hyperplasia in patients with moderate-to-severe lower urinary tract symptoms.