Does the addition of targeted prostate biopsies to standard systemic biopsies influence treatment management for radiation oncologists?

OBJECTIVES: To study the management impact that magnetic resonance imaging (MRI)-guided targeted prostate biopsies could provide relative to using only non-targeted systematic biopsies in men with clinically localized prostate cancer (PCa). PATIENTS AND METHODS: A consecutive series of untreated men undergoing Artemis (MRI-ultrasonography fusion) biopsies between March 2010 and June 2013 was evaluated in this retrospective, institutional review board-approved study. Fusion biopsy included MRI-targeted and systematic sampling at the same session. 3-Tesla multiparametric MRI was performed at a median of 2 weeks before biopsy. Patients were included if ≥1 systematic core was found to harbour PCa. The impact of the information obtained from targeted vs systematic biopsies was studied with regard to the following: Gleason score (GS), National Comprehensive Cancer Network (NCCN) risk reclassification, cancer core length, percentage of core positive for tumour involvement, and percentage of positive biopsy cores. RESULTS: The study sample included 215 men (mean ± sd age 66 ± 8 years). The median (range) prostate-specific antigen (PSA) was 6.0 (0.7-181) ng/mL. The mean number of total biopsy samples was 18 (12 systematic and six targeted samples). Of 215 men, 34 (16%) had a higher GS on targeted vs systematic biopsy. A total of 21/183 men (12%) were stratified into a higher NCCN risk group when incorporating targeted biopsy GS results and 18/101 men (18%) were upgraded to intermediate- or high-risk from the low-risk group. Among the 34 men whose cancer severity was upgraded, increases in cancer core length, percentage of tumour involvement and percentage of cores involved were all statistically significant (P < 0.01). CONCLUSION: Targeted prostate biopsy provided information about GS, NCCN risk and tumour volume beyond that obtained in systematic biopsies, specifically increasing the proportions of men in the intermediate- and high-risk groups. Such men may be recommended for additional treatments (pelvic nodal irradiation or hormonal therapy). The appropriateness of changing treatment because of targeted biopsy results is still unclear.

Magnetic resonance imaging-ultrasound fusion biopsy for prediction of final prostate pathology.

PURPOSE: We explored the impact of magnetic resonance imaging-ultrasound fusion prostate biopsy on the prediction of final surgical pathology. MATERIALS AND METHODS: A total of 54 consecutive men undergoing radical prostatectomy at UCLA after fusion biopsy were included in this prospective, institutional review board approved pilot study. Using magnetic resonance imaging-ultrasound fusion, tissue was obtained from a 12-point systematic grid (mapping biopsy) and from regions of interest detected by multiparametric magnetic resonance imaging (targeted biopsy). A single radiologist read all magnetic resonance imaging, and a single pathologist independently rereviewed all biopsy and whole mount pathology, blinded to prior interpretation and matched specimen. Gleason score concordance between biopsy and prostatectomy was the primary end point. RESULTS: Mean patient age was 62 years and median prostate specific antigen was 6.2 ng/ml. Final Gleason score at prostatectomy was 6 (13%), 7 (70%) and 8-9 (17%). A tertiary pattern was detected in 17 (31%) men. Of 45 high suspicion (image grade 4-5) magnetic resonance imaging targets 32 (71%) contained prostate cancer. The per core cancer detection rate was 20% by systematic mapping biopsy and 42% by targeted biopsy. The highest Gleason pattern at prostatectomy was detected by systematic mapping biopsy in 54%, targeted biopsy in 54% and a combination in 81% of cases. Overall 17% of cases were upgraded from fusion biopsy to final pathology and 1 (2%) was downgraded. The combination of targeted biopsy and systematic mapping biopsy was needed to obtain the best predictive accuracy. CONCLUSIONS: In this pilot study magnetic resonance imaging-ultrasound fusion biopsy allowed for the prediction of final prostate pathology with greater accuracy than that reported previously using conventional methods (81% vs 40% to 65%). If confirmed, these results will have important clinical implications.

Anatomic and technical considerations for optimizing recovery of sexual function during robotic-assisted radical prostatectomy.

PURPOSE OF REVIEW: Although cure of prostate cancer is the primary goal of radical prostatectomy, preserving erectile function is also tantamount, given the indolent clinical course of most prostate cancers, particularly low-risk disease. In order to optimize postprostatectomy erectile function during a robotic-assisted radical prostatectomy, there must be a detailed understanding of pelvic anatomy to recognize the optimal nerve-sparing plane and technical finesse to minimize stretch injury to the neurovascular bundle. RECENT FINDINGS: The magnified, well illuminated robotic-operative field coupled with less blood loss has paralleled greater understanding of the periprostatic 'fascial' planes, leading to differentiation of intrafascial versus interfascial nerve-sparing approaches. However, refinement of tissue handling during nerve-sparing to minimize lateral displacement of the neurovascular bundle and attenuate neurapraxia enables earlier and better recovery of erectile function. SUMMARY: The critical maneuvers to preserving erectile function are atraumatic dissection of the prostate away from the optimal nerve-sparing plane to maximally preserve nerve fibers while minimizing neurapraxia. Therefore, attaining these principles involves a conceptual paradigm shift from 'radical' prostatectomy to neurosurgery of the prostate.

Laterality of nephrocalcinosis in kidney stone formers with severe hypocitraturia.

OBJECTIVE To examine the hypothesis that the distribution of nephrocalcinosis in patients with severe hypocitraturia should be symmetric. PATIENTS AND METHODS Patients with profound hypocitraturia defined as a 24-h urine citrate < 50 mg at the time of initial presentation were identified from the metabolic stone clinic database at our academic medical center. Two independent blinded reviewers evaluated all of the abdominal radiographs for the segmental distribution of macroscopic nephrocalcinosis. RESULTS A total of 44 patients met study criteria, with an equal distribution of males and females and a mean age of 55.4 ± 13.7 years. Mean urinary citrate was 28 ± 11 mg/day. Nephrocalcinosis was present in at least one renal segment in 22 patients (50%). Of the 22 patients with nephrocalcinosis, 9 patients (41%) had unilateral nephrocalcinosis and 13 patients (59%) had bilateral nephrocalcinosis. Of the 35 kidneys with nephrocalcinosis, 14 kidneys (40%) had nephrocalcinosis in only one renal segment, 13 kidneys (37%) had nephrocalcinosis in two segments and eight kidneys (23%) had nephrocalcinosis involving all three segments. CONCLUSIONS Despite the systemic nature of severe hypocitraturia, nephrocalcinosis is frequently asymmetric and focal in nature. This suggests that local factors intrinsic to the renal medullary interstitium, such as vascular injury, must play a role in the formation of nephrocalcinosis. Further study to elucidate these intrinsic local factors may further improve the treatment and prevention of urinary stone disease.

Changes in specific domains of sexual function and sexual bother after radical prostatectomy.

OBJECTIVE: To quantitatively assess the effect of radical prostatectomy (RP) on the specific domains that comprise overall sexual function (SF), focusing on the relationships among these domains and overall SF, and to identify predictors for recovery of SF over time, as a decline in SF and sexual bother (SB) are known potential complications of treatment for prostate cancer. PATIENTS AND METHODS: Within the Cancer of the Prostate Strategic Urologic Research Endeavor database, we identified men diagnosed between 1995 and 2001 with localized prostate cancer treated with RP. SF and SB outcomes, measured using the University of California Los Angeles Prostate Cancer Index, were assessed at 6-month intervals for 4 years after RP. RESULTS: In all, 620 men met the study criteria; at 6 months after RP, overall and all the specific domains of SF declined, with improvement in most specific domains by 2 years after RP. The greatest declines were in the ability to achieve erections, high-quality erections, and frequent erections; these domains were also most strongly correlated with overall SF. Sexual desire was relatively preserved, and there was a weak correlation between overall SF and sexual desire after RP, when there was the greatest discrepancy between sexual desire and other domains of function. SB showed continued improvement over time to 4 years but was not well correlated with any measurements of SF assessed. Younger age, college education, sexual aid and medication use, the absence of comorbid conditions, and nerve-sparing surgery were predictive of significant recovery of function in several specific domains of SF. CONCLUSIONS: RP affects specific domains of SF to differing degrees. Compromised erectile function is most commonly reported among these specific domains and seems to play a more dominant role in determining overall SF, but notably none of the domains of function were closely linked to SB. Because education is protective in the perception of bother, appropriate counselling and the setting of expectations for outcomes in overall and specific domains of SF might lead to improved quality of life after treatment for prostate cancer.

Multifocality and prostate cancer detection by multiparametric magnetic resonance imaging: correlation with whole-mount histopathology.

BACKGROUND: Multiparametric magnetic resonance imaging (mp-MRI) is increasingly used in prostate cancer (CaP). Understanding the limitations of tumor detection, particularly in multifocal disease, is important in its clinical application. OBJECTIVE: To determine predictors of CaP detection by mp-MRI as confirmed by whole-mount histopathology. DESIGN, SETTING, AND PARTICIPANTS: A retrospective study was performed of 122 consecutive men who underwent mp-MRI before radical prostatectomy at a single referral academic center. A genitourinary radiologist and pathologist collectively determined concordance. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The odds of tumor detection were calculated for clinical, MRI, and histopathologic variables using a multivariate logistic regression model. RESULTS AND LIMITATIONS: The 122 patients had 283 unique histologically confirmed CaP tumor foci. Gleason score was 6 in 21 (17%), 7 in 88 (72%), and ≥8 in 13 (11%) patients. Of the 122 cases, 44 (36%) had solitary and 78 (64%) had multifocal tumors. Overall mp-MRI sensitivity for tumor detection was 47% (132/283), with increased sensitivity for larger (102/141 [72%] >1.0 cm), higher-grade (96/134 [72%] Gleason ≥7) tumors, and index tumors (98/122 [80%]). Index tumor status, size, and prostate weight were significant predictors of detection in a multivariate analysis, and multifocality did not adversely impact detection of index tumors. A prostatectomy population was necessary by design, which may limit the ability to generalize these results. CONCLUSIONS: Sensitivity for tumor detection increased with tumor size and grade. Index tumor status and tumor size were the strongest predictors of tumor detection, regardless of tumor focality. Some 80% of index tumors were detected, but nonindex tumor detection, even of high-grade lesions, was poor. These findings have important implications for focal therapy. PATIENT SUMMARY: We evaluated the ability of magnetic resonance imaging (MRI) to detect cancer in patients undergoing prostatectomy. We found that tumor size and grade were important predictors of tumor detection, and although cancer is often multifocal, MRI is often able to detect the worst focus of cancer.

Targeted prostate biopsy: value of multiparametric magnetic resonance imaging in detection of localized cancer.

Prostate cancer is the second most common cancer in men, with 1.1 million new cases worldwide reported by the World Health Organization in one recent year. Transrectal ultrasound (TRUS)-guided biopsy has been used for the diagnosis of prostate cancer for over 2 decades, but the technique is usually blind to cancer location. Moreover, the false negative rate of TRUS biopsy has been reported to be as high as 47%. Multiparametric magnetic resonance imaging (mp-MRI) includes T1- and T2-weighted imaging as well as dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI). mp-MRI is a major advance in the imaging of prostate cancer, enabling targeted biopsy of suspicious lesions. Evolving targeted biopsy techniques-including direct in-bore biopsy, cognitive fusion and software-based MRI-ultrasound (MRI-US) fusion-have led to a several-fold improvement in cancer detection compared to the earlier method. Importantly, the detection of clinically significant cancers has been greatly facilitated by targeting, compared to systematic biopsy alone. Targeted biopsy via MRI-US fusion may dramatically alter the way prostate cancer is diagnosed and managed.

A system for evaluating magnetic resonance imaging of prostate cancer using patient-specific 3D printed molds.

We have developed a system for evaluating magnetic resonance imaging of prostate cancer, using patient-specific 3D printed molds to facilitate MR-histology correlation. Prior to radical prostatectomy a patient receives a multiparametric MRI, which an expert genitourinary radiologist uses to identify and contour regions suspicious for disease. The same MR series is used to generate a prostate contour, which is the basis for design of a patient-specific mold. The 3D printed mold contains a series of evenly spaced parallel slits, each of which corresponds to a known MRI slice. After surgery, the patient's specimen is enclosed within the mold, and all whole-mount levels are obtained simultaneously through use of a multi-bladed slicing device. The levels are then formalin fixed, processed, and delivered to an expert pathologist, who identifies and grades all lesions within the slides. Finally, the lesion contours are loaded into custom software, which elastically warps them to fit the MR prostate contour. The suspicious regions on MR can then be directly compared to lesions on histology. Furthermore, the false-negative and false-positive regions on MR can be retrospectively examined, with the ultimate goal of developing methods for improving the predictive accuracy of MRI. This work presents the details of our analysis method, following a patient from diagnosis through the MR-histology correlation process. For this patient MRI successfully predicted the presence of cancer, but true lesion volume and extent were underestimated. Most cancer-positive regions missed on MR were observed to have patterns of low T2 signal, suggesting that there is potential to improve sensitivity.