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Introduction The efficacy of olaparib for treatment‐related neuroendocrine prostate cancer is unknown. Here, we report a case of treatment‐related neuroendocrine prostate cancer with a BRCA2 mutation that was treated with olaparib with 1‐year efficacy. Case presentation A 75‐year‐old man initially diagnosed with prostate adenocarcinoma developed treatment‐related neuroendocrine prostate cancer after 10‐year androgen deprivation therapy. Despite the initial temporary effects of etoposide and carboplatin, the patient experienced prostate bed tumor recurrence 1 year after chemotherapy cessation. FoundationOne® detected a BRCA2 gene mutation, and olaparib was initiated after repeating one chemotherapy course using the same chemotherapeutic agents. The patient received olaparib with sustained tumor regression for 1 year without severe side effects. Conclusion Olaparib may be the treatment of choice for treatment‐related neuroendocrine prostate cancer in patients with BRCA mutations.

Abstract Background The significance of metastasis-directed therapy for oligometastatic prostate cancer has been widely discussed, and targeted therapy for progressive sites is a feasible option as a multidisciplinary treatment for castration-resistant prostate cancer (CRPC). When oligometastatic CRPC with only bone metastases progresses after targeted therapy, it tends to progress as multiple bone metastases. The progression of oligometastatic CRPC after targeted therapy may be due in part to the presence of micrometastatic lesions that, though undetected on imaging, were present prior to targeted therapy. Thus the systemic treatment of micrometastases in combination with targeted therapy for progressive sites is expected to enhance the therapeutic effect. Radium-223 dichloride (radium-223) is a radiopharmaceutical that selectively binds to sites of increased bone turnover and inhibits the growth of adjacent tumor cells by emitting alpha rays. Therefore, for oligometastatic CRPC with only bone metastases, radium-223 may enhance the therapeutic effect of radiotherapy for active metastases. Methods This phase II, randomized trial of Metastasis-Directed therapy with ALpha emitter radium-223 in men with oligometastatic CRPC (MEDAL) is designed to assess the utility of radium-223 in combination with metastasis-directed radiotherapy in patients with oligometastatic CRPC confined to bone. In this trial, patients with oligometastatic CRPC with three or fewer bone metastases on whole-body MRI with diffusion-weighted MRI (WB-DWI) will be randomized in a 1:1 ratio to receive radiotherapy for active metastases plus radium-223 or radiotherapy for active metastases alone. The prior use of androgen receptor axis-targeted therapy and prostate-specific antigen doubling time will be used as allocation factors. The primary endpoint will be radiological progression-free survival against progression of bone metastases on WB-DWI. Discussion This will be the first randomized trial to evaluate the effect of radium-223 in combination with targeted therapy in oligometastatic CRPC patients. The combination of targeted therapy for macroscopic metastases with radiopharmaceuticals targeting micrometastasis is expected to be a promising new therapeutic strategy for patients with oligometastatic CRPC confined to bone. Trial registration Japan Registry of Clinical Trials (jRCT) (jRCTs031200358); Registered on March 1, 2021, https://jrct.niph.go.jp/latest-detail/jRCTs031200358

Background: Unexpected adverse pathology is a major concern in surgical management of clinically localised renal cell carcinoma (RCC). Further studies are needed to improve preoperative risk stratification. Objective: To define and classify tumour shape irregularity (TSI) based on preoperative imaging, and to investigate its effect on pathological and oncological outcomes in clinically localised RCC. Design, setting, and participants: We retrospectively analysed 474 patients with cT1-2N0M0 RCC managed by partial or radical nephrectomy. Preoperative dynamic computed tomography was used to define and classify TSI, graded as 1 (completely elliptical shape), 2 (elliptical shape with minor and focal protrusions), or 3 (nonelliptical shape presenting with major and/or extensive protrusions). Intervention: Partial or radical nephrectomy. Outcome measurements and statistical analysis: A logistic regression analysis evaluated the risk factors for pT3a upstaging and Fuhrman grade 3–4. A Cox proportional hazard analysis assessed preoperative variables for recurrence-free survival (RFS). Results and limitations: The median tumour size was 3.5 cm, and 94 patients (20%) had (R)adius (tumour size as maximal diameter), (E)xophytic/endophytic properties of tumour, (N)earness of tumour deepest portion to collecting system or sinus, (A)nterior (a)/posterior (p) descriptor, and (L)ocation relative to polar lines (RENAL) score ≥10. TSI was graded as 1, 2, and 3 in 214 (45%), 151 (32%), and 109 (23%) patients, respectively. Higher TSI was significantly associated with a larger tumour size and a higher RENAL score. Overall, pT3a upstaging and Fuhrman grade 3–4 were observed in 45 (9.5%) and 116 patients (31% in 380 clear cell RCC cases), respectively. The incidence of pT3a upstaging and Fuhrman grade 3–4 was significantly higher in patients with higher TSI (0.5%, 8.6%, and 28% for pT3a upstaging and 12%, 33%, and 60% for Fuhrman grade 3–4 in TSI 1, 2, and 3 groups, respectively). In multivariable analyses, higher TSI was independently associated with adverse pathological outcomes. During the median follow-up of 6.0 yr, 49 patients (10%) developed recurrence. Multivariable analyses demonstrated that older age and higher TSI were independent risk factors for worse RFS. The limitations include the retrospective design. Conclusions: TSI may be a useful adjunct in preoperative risk stratification for adverse pathology and recurrence after surgery in clinically localised RCC. Patient summary: Tumour shape irregularity is significantly associated with unfavourable pathological outcomes, that is, locally advanced stage or high-grade cancer, and with a higher recurrence rate after surgery in patients with clinically localised renal cell carcinoma. Preoperative evaluation of the tumour shape may help in patient counselling and treatment decisions.

The accurate classification of kidney tumors necessitates the utilization of various diagnostic techniques. Within the domain of medical imaging tests, the integration of multi-modal medical imaging represents an innovative approach to enhance diagnostic precision. However, the integration of multi-modal medical imaging faces a critical challenge: the insufficiency of correspondingly paired data across modalities, resulting in a paucity of training samples for neural networks. To mitigate this limitation, generative artificial intelligence, specifically generative models capable of generating additional data, thereby addressing the gap in the multi-modal medical imaging record. In our work, our primary objective is to improve the classification results that outperform an existing method of using single-modal medical images. To achieve this, we harness the wealth of information of multi-modal data derived from Contrast-Enhanced Computed Tomography (CECT) and Magnetic Resonance Imaging (MRI), along with their respective subtypes, to determine which specific modality or pair contributes the most effectively to classification. Our work introduces the comprehensive comparison between the different multi-modal fusion techniques, in which the Area Under the Curve (AUC) serves as the benchmark for performance evaluation. Moreover, this work tackles the problem of the unavailability of kidney tumor data by partially recovering from the available data using Conditional CycleGAN, which is part of the image-to-image translation that maps between two different image domains. Through the employment of multi-modal fusion techniques and our proposed recovery of missing data, our research has yielded superior classification results than single-modal classification approaches.

In this research, we proposed a two-stage pipeline for segmenting urinary stones. The first stage U-Net generated the map localizing the urinary organs in full abdominal x-ray images. Then, this map was used for creating partitioned images input to the second stage U-Net to reduce class imbalance and was also used in stone-embedding augmentation to increase a number of training data. The U-Net model was trained with the combination of real stone-contained images and synthesized stone-embedded images to segment urinary stones on the partitioned input images. In addition, we proposed to use an inverse weighting method in the focal Tversky loss function in order to rebalance lesion size. The U-Net model using our proposed pipeline produced a 71.28% pixel-wise $F_{2}$ score and a 69.82% region-wise $F_{2}$ score, which were 2.88% and 7.63%, respectively, higher than those of a baseline method. Experimental results showed that the proposed method improved urinary stone segmentation results, especially for small stones and stones in uncommon locations.

Introduction SDH Gene mutation is known to be a common cause of pheochromocytoma/paraganglioma and renal cell carcinoma. Here, we report a case of succinate dehydrogenase B‐deficient paraganglioma, which has a high risk of metastasis and recurrence, complicated by succinate dehydrogenase‐deficient renal cell carcinoma, which is rare and accounts for approximately 0.1% of all renal cell carcinomas. Case presentation A 50‐year‐old man underwent en bloc resection of a retroperitoneal tumor and the right kidney for retroperitoneal paraganglioma and right renal tumor. Both tumors showed negative expressions of succinate dehydrogenase B in immunostaining. The patient was diagnosed with succinate dehydrogenase‐deficient paraganglioma and succinate dehydrogenase‐deficient renal cell carcinoma. Seventeen months later, retroperitoneal lymphadenectomy revealed lymph node metastasis of the paraganglioma. Deletion of the SDHB gene was revealed by genome sequencing of the lymph node. Conclusion This is the first reported case of synchronously diagnosed succinate dehydrogenase‐deficient paraganglioma and succinate dehydrogenase‐deficient renal cell carcinoma.

A urinary stone is a type of abnormality that occurs frequently in the urinary system. An automated segmentation of urinary stones is important for assisting medical doctors in early diagnosis and further treatment. While deep learning techniques are effective for image segmentation, they require a large number of datasets to achieve high accuracy. We proposed a GAN-based augmentation technique for creating synthetic images based on stone and non-stone mask inputs in order to improve the segmentation network’s performance by increasing the number and diversity of training data. The synthetic training images were generated from stone-contained images and stone-free images using existing stone ground truth and corresponding stone location maps, respectively. To segment urinary stones from full abdominal x-ray images, we trained the MultiResUnet model using both original stone-contained and our proposed synthetic samples. The proposed method obtained a 69.59% pixel-wise $F_{1}$ score and a 68.14% region-wise $F_{1}$ score, which achieved an improvement of 2.12% and 2.13%, respectively, over a model trained with only the original stone-contained dataset.

Large cell calcifying Sertoli tumor is an uncommon testicular neoplasm. We present a case of a 36-year-old man with a late-onset large cell calcifying Sertoli tumor that resulted in a solitary lung metastasis 5 years after radical orchiectomy. Pulmonary wedge resection was performed, and there was no recurrence at the 18-month follow-up after resection of the lung metastasis. Because of its malignant potential, late-onset large cell calcifying Sertoli tumor requires long-term follow-up.

Abstract Background Recent increased use of medical images induces further burden of their interpretation for physicians. A plain X-ray is a low-cost examination that has low-dose radiation exposure and high availability, although diagnosing urolithiasis using this method is not always easy. Since the advent of a convolutional neural network via deep learning in the 2000s, computer-aided diagnosis (CAD) has had a great impact on automatic image analysis in the urological field. The objective of our study was to develop a CAD system with deep learning architecture to detect urinary tract stones on a plain X-ray and to evaluate the model’s accuracy. Methods We collected plain X-ray images of 1017 patients with a radio-opaque upper urinary tract stone. X-ray images (n = 827 and 190) were used as the training and test data, respectively. We used a 17-layer Residual Network as a convolutional neural network architecture for patch-wise training. The training data were repeatedly used until the best model accuracy was achieved within 300 runs. The F score, which is a harmonic mean of the sensitivity and positive predictive value (PPV) and represents the balance of the accuracy, was measured to evaluate the model’s accuracy. Results Using deep learning, we developed a CAD model that needed 110 ms to provide an answer for each X-ray image. The best F score was 0.752, and the sensitivity and PPV were 0.872 and 0.662, respectively. When limited to a proximal ureter stone, the sensitivity and PPV were 0.925 and 0.876, respectively, and they were the lowest at mid-ureter. Conclusion CAD of a plain X-ray may be a promising method to detect radio-opaque urinary tract stones with satisfactory sensitivity although the PPV could still be improved. The CAD model detects urinary tract stones quickly and automatically and has the potential to become a helpful screening modality especially for primary care physicians for diagnosing urolithiasis. Further study using a higher volume of data would improve the diagnostic performance of CAD models to detect urinary tract stones on a plain X-ray.

Introduction The efficacy of salvage local therapy after external beam radiotherapy has recently gained attention. However, a challenge with these therapies is the risk of significant genitourinary and gastrointestinal toxicity. Focal brachytherapy may be a treatment option because of its potential to reduce side effects. Case presentation A patient with castration‐resistant prostate cancer was found to be free of metastases on whole‐body magnetic resonance imaging following external beam radiotherapy, and prostate biopsy revealed a localized recurrence in the ventral prostate. The patient underwent salvage focal brachytherapy and had a prostate‐specific antigen progression‐free survival of 23 months. No adverse effects were observed following salvage brachytherapy. Conclusion Our case suggests that salvage focal brachytherapy may be an effective local treatment option for nonmetastatic castration‐resistant prostate cancer that has relapsed after external beam radiotherapy, wherein the lesion is confined to a small area within the prostate.

Abstract Radiotherapy plus immune checkpoint inhibitors can potentially induce synergistic antitumor immune responses. However, little clinical evidence is established regarding their combination therapy. Here, we aimed to assess whether radiotherapy to the primary tumor impacts on the efficacy of pembrolizumab in advanced urothelial cancer. We retrospectively reviewed 98 advanced urothelial cancer patients receiving pembrolizumab in a second‐ or later‐line setting using our multicenter cohort. Patients were categorized according to a history of radiotherapy to the primary tumor: patients previously exposed to radiotherapy to the primary tumor (Radiotherapy group, 17 patients [17%]) and those not (Nonradiotherapy group, 81 patients [83%]). The associations of radiotherapy to the primary tumor with objective response and survival were evaluated. The Radiotherapy group showed a significantly higher objective response ratio than did the Non‐radiotherapy group (65% vs 19%; P

Background The dynamic change in C-reactive protein (CRP) levels, CRP kinetics, is a prognostic factor for metastatic renal cell carcinoma (mRCC) in the tyrosine kinase inhibitor era. We investigated the impact of early CRP kinetics on the efficacy of nivolumab in patients with mRCC.Methods We performed a retrospective analysis of 42 mRCC patients who were treated with nivolumab as a second-line or later therapy between 2016 and 2019. All patients had received previous TKI therapy. Patients were divided into three groups based on their early CRP kinetics: CRP levels increased to more than double compared with baseline within 1 month after initiation of nivolumab (flare) and then decreased to a lower value than baseline within 3 months (CRP flare-responders); CRP levels decreased by ≥30% within 3 months without “flare” (CRP responders); and the remaining patients (non-CRP responders). The maximum tumor shrinkage, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) were evaluated. The association of the early CRP kinetics and oncological outcomes was assessed.Results The median follow-up period was 8 months. The median baseline CRP level was 23 mg/L. CRP flare-responders, CRP responders, and non-CRP responders included 11 (26%), 15 (36%), and 16 (38%) patients, respectively. Thirteen patients (31%) died of mRCC. The maximum changes in target lesions from baseline of CRP flare-responder, CRP-responder, and non-CRP responder groups were −38%, −13%, and 16%, on average, respectively (p

Preoperative imaging differentiation between ChRCC and RO is difficult with conventional subjective evaluation, and the development of quantitative analysis is a clinical challenge. Forty-nine patients underwent partial or radical nephrectomy preceded by MRI and followed by pathological diagnosis with ChRCC or RO (ChRCC: n = 41, RO: n = 8). The whole-lesion volume of interest was set on apparent diffusion coefficient (ADC) maps of 1.5T-MRI. The importance of selected texture features (TFs) was evaluated, and diagnostic models were created using random forest (RF) analysis. The Mean Decrease Gini as calculated through RF analysis was the highest for mean_ADC_value. ChRCC had a significantly lower mean_ADC_value than RO (1.26 vs. 1.79 × 10−3 mm2/s, p < 0.0001). Feature selection by the Boruta method identified the first-quartile ADC value and GLZLM_HGZE as important features. ROC curve analysis showed that there was no significant difference in the classification performances between the mean_ADC_value-only model and the Boruta model (AUC: 0.954 vs. 0.969, p = 0.236). The mean ADC value had good predictive ability for the distinction between ChRCC and RO, comparable to that of the combination of TFs optimized for the evaluated cohort. The mean ADC value may be useful in distinguishing between ChRCC and RO.

Prognostic accuracy of the quick sequential organ failure assessment (qSOFA) score for mortality may be limited in elderly patients. Using our multi-institutional database, we classified obstructive acute pyelonephritis (OAPN) patients into young and elderly groups, and evaluated predictive performance of the qSOFA score for in-hospital mortality. qSOFA score ≥ 2 was an independent predictor for in-hospital mortality, as was higher age, and Charlson comorbidity index (CCI) ≥ 2. In young patients, the area under the curve (AUC) of the qSOFA score for in-hospital mortality was 0.85, whereas it was 0.61 in elderly patients. The sensitivity and specificity of qSOFA score ≥ 2 for in-hospital mortality was 80% and 80% in young patients, and 50% and 68% in elderly patients, respectively. For elderly patients, we developed the CCI-incorporated qSOFA score, which showed higher prognostic accuracy compared with the qSOFA score (AUC, 0.66 vs. 0.61, p < 0.001). Therefore, the prognostic accuracy of the qSOFA score for in-hospital mortality was high in young OAPN patients, but modest in elderly patients. Although it can work as a screening tool to determine therapeutic management in young patients, for elderly patients, the presence of comorbidities should be considered at the initial assessment.

Purpose We tested a new head-mounted display (HMD) system for surgery on the upper urinary tract. Surgical Technique Four women and one man with abnormal findings in the renal pelvis on computed tomography and magnetic resonance imaging underwent surgery using this new system. A high definition HMD (Sony, Tokyo, Japan) is connected to a flexible ureteroscope (Olympus, Tokyo, Japan) and the images from the ureteroscope are delivered simultaneously to various participants wearing HMDs. Furthermore, various information in addition to that available through the endoscope, such as the narrow band image, the fluoroscope, input from a video camera mounted on the lead surgeon’s HMD and the vital monitors can be viewed on each HMD. Results Median operative duration and anesthesia time were 53 and 111 minutes, respectively. The ureteroscopic procedures were successfully performed in all cases. There were no notable negative outcomes or incidents (Clavien-Dindo grade ≥1). Conclusion The HMD system offers simultaneous, high-quality magnified imagery in front of the eyes, regardless of head position, to those participating in the endoscopic procedures. This affordable display system also provides various forms of information related to examinations and operations while allowing direct vision and navigated vision.

We present an application of head-mounted display (HMD) to patient's self-monitoring of transurethral resection of bladder tumor (TURB). Six patients wore the HMD as an imaging monitor to view the operation in real-time during their TURB. Following the operation, the patients completed a questionnaire that evaluates understanding of the state of their disease and satisfaction with the HMD. As a result, monitoring the operation in real time through the HMD helped to increase patients' understanding of the state of their disease and satisfaction. For selected patients, the use of HMD could help to increase the patient's understanding of their disease.

An association between the development of overall or specific immune-related adverse events (irAEs) and outcomes of immune checkpoint inhibitors has recently been suggested. To address this emerging association in patients with urothelial cancer receiving pembrolizumab, we conducted a multicenter retrospective analysis, which is the first and largest in an Asian cohort as well as a systematic literature review. We retrospectively evaluated 97 patients with advanced urothelial cancer treated with pembrolizumab as second- or later-line treatment between January 2018 and March 2019. irAEs were categorized by the involved organs and graded using Common Terminology Criteria for Adverse Events version 5.0. Associations between irAEs and pembrolizumab efficacy, including objective response rate (ORR), progression-free survival (PFS), and overall survival (OS), were evaluated. In our review of the literature, 28 studies, including 9 studies involving patients with urothelial cancer and 19 studies reporting the association between outcomes and spectrum of irAEs, were analyzed. Patients with irAEs had significantly higher ORR (52% vs. 16%, P < .01), longer PFS (11.0 months vs. 3.6 months, P < .01) and OS (median not reached vs. 13.1 months, P = .12) than in patients without irAEs. Endocrine (P = .02), pneumological (P = .06), and other (gastrointestinal, hematological, hepatic) (P = .04) irAEs were associated with increased ORR, whereas skin irAEs were not. Endocrine irAEs (P = .04) was associated with improved OS, whereas pneumological and skin irAEs were not. The association between the occurrence of irAEs and clinical efficacy of immune checkpoint inhibitors was consistently supported by the multiple studies we reviewed. The association between clinical outcomes and the spectrum of organs/systems affected by irAEs seems to be inconsistent and could be dependent on tumor type. irAEs were associated with a higher ORR and better survival of patients with advanced urothelial cancer treated with pembrolizumab. [ABSTRACT FROM AUTHOR]

Background: The shortage of surgeon is one of the serious problems in Japan. To solve the problem, various efforts have been undertaken to improve surgical education and training. However, appropriate teaching methods in the operating room have not been well established. The aim of this study is to assess the utility of a novel interactive educational (IE) system for surgical education on urologic surgeries in the operating room. Methods: A total of 20 Japanese medical students were educated on urologic surgery using the IE system in the operating room. The IE system consists of two parts. The first is three-dimensional (3D) magnified vision of the operative field using a 3D head-mounted display and a 3D endoscope. The second is interactive educative communication between medical students and surgeons using a small-sized wireless communication device. The satisfaction level with the IE system and the physical burden on medical students was examined via questionnaire. Results: All students utilized the IE system in urologic surgery and responded to the survey. Most students were satisfied with the IE system. They also felt more welcomed by the surgeon when using the IE system than when not using it. No major unpleasant symptoms were observed but five students (25 %) experienced mild eye fatigue as a result of viewing the medical images. Conclusions: The IE system has the potential to motivate students to become interested in surgery and could be an efficient method of surgical education in the operating room. [ABSTRACT FROM AUTHOR]

The safety and efficacy of minimally invasive surgery relies on visual information. We aimed to develop an integrated image navigation system (RoboSurgeon System) that combines head-mounted displays (HMDs) with multiple image modalities, and assessed its feasibility in 5 prostate cancer patients who underwent gasless single-port endoscopic radical prostatectomy. A robotically manipulated transrectal ultrasound (TRUS) system was used. In all cases, preoperative magnetic resonance (MR) images and intraoperative real-time images of an endoscope, TRUS, and HMD-mounted camera were integrated and displayed synchronously on each HMD in a four-split screen mode during the entire process. The TRUS helped identify the boundary with the adjacent structures endoscopically in reference to MR images. There were no negative incidents in intraoperative or postoperative courses. Integrated image navigation using HMDs as individualized monitors is feasible in the natural ergonomic position and may be beneficial to identify correct dissection planes. The efficacy of the RoboSurgeon System deserves further evaluation. [ABSTRACT FROM AUTHOR]

We developed a new three-dimensional (3D) head-mounted display (HMD) system (RoboSurgeon system) that combines a high-definition 3D organic electroluminescent HMD with a high-definition 3D endoscope and applies it to minimally invasive surgery. This system presents the surgeon with a higher quality of magnified 3D imagery in front of the eyes, regardless of head position. We report 5 cases of RoboSurgeon gasless laparoendoscopic single-port partial cystectomy, which is carried out as part of our selective bladder-sparing protocol, with a technique utilizing both an intravesical and extravesical approach. While carrying out the surgery, the system provides the surgeon with both excellent 3D imagery of the operative field and clear imagery of the cystoscopy. All procedures were safely completed and there were no complications except for a case of postoperative lymphorrhea. Our experience shows that the 3D HMD system might facilitate maneuverability and safety in various minimally invasive procedures. [ABSTRACT FROM AUTHOR]

Purpose: We evaluated the usefulness of pre-biopsy multiparametric magnetic resonance imaging and clinical variables to decrease initial prostate biopsies. Materials and Methods: We prospectively evaluated 351 consecutive men with prostate specific antigen between 2.5 and 20 ng/ml, and/or digital rectal examination suspicious for clinically localized disease. All men underwent pre-biopsy multiparametric magnetic resonance imaging and initial 14 to 29-core biopsy, including anterior sampling. Three definitions of significant cancer were defined based on Gleason score and cancer volume (percent positive core and/or maximum cancer length). The overall cohort was divided into men at low risk--prostate specific antigen less than 10 ng/ml and normal digital rectal examination, and high risk--prostate specific antigen 10 ng/ml or greater and/or abnormal digital rectal examination. We evaluated the frequency of significant cancer according to magnetic resonance imaging and risk categories. Clinical variables as significant cancer predictors were analyzed using logistic regression. The sensitivity, specificity, and positive and negative predictive values of magnetic resonance imaging were calculated with or without clinical variables for significant cancer. Results: The frequency of significant cancer in men with negative vs positive magnetic resonance imaging was 9% to 13% vs 43% to 50% in the low risk group and 47% to 51% vs 68% to 71% in the high risk group. In men at low risk with negative magnetic resonance imaging prostate volume was the only significant predictor of significant cancer. In the low risk group the negative predictive value for significant cancer of a combination of positive magnetic resonance imaging and lower prostate volume (less than 33 ml) was 93.7% to 97.5%. Conclusions: Pre-biopsy multiparametric magnetic resonance imaging along with prostate volume decreases the number of initial prostate biopsies by discriminating between significant cancer and other cancer in men with prostate specific antigen less than 10 ng/ml and normal digital rectal examination. [ABSTRACT FROM AUTHOR]