Value of preoperative 3T multiparametric MRI for surgical margin status in patients with prostate cancer.

PURPOSE: To examine the value of preoperative multiparametric magnetic resonance imaging (MRI) as a predictor of surgical margin (SM) status in patients with prostate cancer (PC). MATERIALS AND METHODS: The Institutional Review Board approved this retrospective study; the requirement for informed consent was waived. Fifty-six male patients with histologically proven PC underwent preoperative 3T multiparametric MRI including high b value (0, 2000 s/mm(2) ) diffusion-weighted imaging. In each patient, clinical data, such as biopsy Gleason score and D'Amico clinical risk score, and multiparametric MRI findings, such as tumor location, tumor size, tumor extension in the apical or proximal region, tumor apparent diffusion coefficient (ADC), and the presence or absence of MRI findings of extracapsular extension (ECE) were evaluated. Statistical evaluations included the Fisher's exact test, χ(2) test, Mann-Whitney U-test, and logistic regression analysis. RESULTS: On histopathological evaluation, 15 patients (27%) were SM-positive (SMP group), and 41 (73%) were SM-negative (SMN group). The tumor ADC was significantly lower in the SMP group than in the SMN group (P = 0.001). The frequency of tumor extension in the apex or base and suspected ECE on MRI were significantly higher in the SMP group than in the SMN group (P = 0.037 and 0.011, respectively). On multivariate analysis, tumor ADC was the only predictor of SM status in PC (P = 0.003). CONCLUSION: PC with positive SM was characterized by tumor extension in the apical and proximal regions, lower tumor ADC, and tumors with positive MRI findings of ECE, compared to tumors with negative SM. J. Magn. Reson. Imaging 2016;44:584-593.

Practical application of color Doppler ultrasonography in patients with ejaculatory dysfunction.

We describe two cases in which dynamic analysis of ejaculation using color Doppler ultrasonography was useful in diagnosis of ejaculatory dysfunction and planning of therapy. The first patient was a 32-year-old man with a diagnosis of retrograde ejaculation. A bladder neck collagen injection was carried out, as the main cause was thought to be the bladder neck remaining open during ejaculation. The patient had antegrade ejaculation 1 week later. The second patient was a 48-year-old man with a diagnosis of anorgasmia accompanied by decreased seminal emission and insufficient function of the rhythmic pelvic striated muscles. The patient was prescribed etilefrine hydrochloride 15 mg/day. The symptom improved 2 weeks after starting this drug. These cases suggest that the use of color Doppler ultrasonography during ejaculation can improve the understanding of ejaculatory dysfunction and therapy for this condition.

High b value (2,000 s/mm2) diffusion-weighted magnetic resonance imaging in prostate cancer at 3 Tesla: comparison with 1,000 s/mm2 for tumor conspicuity and discrimination of aggressiveness.

OBJECTIVE: The objective of our study was to investigate tumor conspicuity and the discrimination potential for tumor aggressiveness on diffusion-weighted magnetic resonance imaging (DW-MRI) with high b value at 3-T. MATERIALS AND METHODS: The institutional review board approved this study and waived the requirement for informed consent. A total of 50 patients with prostate cancer (69 cancer foci; 48 in the PZ, 20 in the TZ, and one in whole prostate) who underwent multiparametric prostate MRI including DW-MRI (b values: 0, 1000 s/mm2 and 0, 2000 s/mm2) on a 3-T system were included. Lesion conspicuity score (LCS) using visual assessment (1 = invisible for surrounding normal site; 2 = slightly high intensity; 3 = moderately high; and 4 = very high) and tumor-normal signal intensity ratio (TNR) were assessed, and apparent diffusion coefficient (ADC, ×10-3 mm2/s) of the tumor regions and normal regions were measured. RESULTS: Mean LCS and TNR at 0, 2000 s/mm2 was significantly higher than those at 0, 1000 s/mm2 (p<0.001 for both). In addition, ADC at both 0, 1000 and 0, 2000 s/mm2 was found to distinguish intermediate or high risk cancer with Gleason score ≥7 from low risk cancer with Gleason score ≤6 (p<0.001 for both). Furthermore, ADC of tumor regions correlated with Gleason score at both 0, 1000 s/mm2 (ρ = -0.602; p<0.001) and 0, 2000 s/mm2 (ρ = -0.645; p<0.001). CONCLUSIONS: For tumor conspicuity and characterization of prostate cancer on DW-MRI of 3-T MRI, b = 0, 2000 s/mm2 is more useful than b = 0, 1000 s/mm2.

Diffusion-weighted MRI and its role in prostate cancer.

In the last 5 years, the multiparametric approach has been investigated as the method for the MRI of prostate cancer. In multiparametric MRI of the prostate, at least two functional MRI techniques, such as diffusion-weighted MRI (DW-MRI) and dynamic contrast-enhanced MRI, are combined with conventional MRI, such as T2 -weighted imaging. DW-MRI has the ability to qualitatively and quantitatively represent the diffusion of water molecules by the apparent diffusion coefficient, which indirectly reflects tissue cellularity. DW-MRI is characterized by a short acquisition time without the administration of contrast medium. Thus, DW-MRI has the potential to become established as a noninvasive diagnostic method for tumor detection and localization, tumor aggressiveness, local staging and local recurrence after various therapies. Accordingly, radiologists should recognize the principles of DW-MRI, the methods of image acquisition and the pitfalls of image interpretation.

Salvage high-dose-rate brachytherapy for local prostate cancer recurrence after radiotherapy - preliminary results.

OBJECTIVE: To assess the preliminary clinical results of salvage high-dose-rate brachytherapy (HDR-BT) applied in cases of suspected local recurrence or of residual tumour after radiotherapy. PATIENTS AND METHODS: The subjects were 11 patients who met the above conditions and underwent salvage HDR-BT between December 2006 and January 2009. The T stage at the initial treatment was T1c in three patients, T2 in three patients and T3 in five patients. Ten patients received HDR-BT ± electron beam radiation therapy and one patient received proton beam irradiation. Follow-up after the completion of salvage HDR-BT lasted 18-41 months (mean 29 months). A dose of 11.0 Gy radiation was delivered twice (22.0Gy in total), separated by a 6-h interval, on the day the applicators were inserted. RESULTS: Seven of the 11 cases remained in a biochemical non-evidence of disease state. The prostate-specific antigen (PSA) level continuously rose after salvage HDR-BT in three of the four other cases. Hormone administration was initiated in the four cases of PSA recurrence. No G3 or more severe events occurred, and the incidence of G2 was low during this study period. CONCLUSION: Of the 11 cases treated with salvage HDR-BT, PSA levels remained low in seven cases and the incidence of complications was also low. This suggests that salvage HDR-BT is effective as an option for treatment of local prostate cancer recurrence after radiotherapy.

Comparison of Two Different α1-Adrenoceptor Antagonists, Tamsulosin and Silodosin, in the Treatment of Male Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Hyperplasia: A Prospective Randomized Crossover Study.

OBJECTIVES: We assessed the efficacy and safety of two α1-adrenoceptor antagonists, tamsulosin and silodosin, in the treatment of male lower urinary tract symptoms. METHODS: Men aged 50 years or older who had a total International Prostate Symptom Score (IPSS) of 8 or higher were enrolled in this study. Forty-six patients were randomized into two groups. Twenty-three patients were initially prescribed tamsulosin 0.2 mg once daily for 3 months, followed by silodosin 4 mg twice daily for 3 months (group T); the other group of 23 patients were initially prescribed silodosin, followed by tamsulosin (group S). Patients then switched to the alternative treatment after a 1-month clearance period. Evaluations included clinical determination of IPSS, quality-of-life index, maximum flow rate and postvoid residual urine volume before and after treatment. RESULTS: A total of 46 men, 23 in group T and 23 in group S, were treated and 41 (89.1%) completed the treatment. IPSS, quality-of-life index, maximum flow rate and postvoid residual urine volume were significantly improved in both groups after treatment. The changes in the total IPSS from baseline in groups S and T at 3 months were -6.6 and -7.5, respectively. There were no significant differences between the two groups. After taking both medications, 18 patients preferred silodosin, 11 preferred tamsulosin and others felt they had the same effects. Six and none patients experienced adverse events during silodosin and tamsulosin treatment, respectively. CONCLUSION: Two types of α1-adrenoceptor antagonists in the same individuals provide similar efficacy. Profiles and difference of each drug should be considered in making treatment choice.

Retroperitoneoscopic nephrectomy for treatment of a case of left single ectopic ureter accompanied by dysplastic kidney.

We report the case of a 7-year-old girl with a single ectopic ureter who was treated with retroperitoneoscopic nephrectomy for a chief complaint of urinary incontinence. Preoperative CT showed a contrasted dysplastic kidney of 1cm in the renal fossa and a left ureteral opening into the vagina. Retroperitoneoscopic left nephrectomy was conducted with opening of the lateroconal fascia to enable identification of the dysplastic kidney. No intraoperative complications were encountered. Urinary incontinence improved immediately after surgery. This case shows that a retroperitoneal approach can be used in nephrectomy if the position of the kidney can be determined preoperatively.

Prostate cancer detection in patients with total serum prostate-specific antigen levels of 4-10 ng/mL: diagnostic efficacy of diffusion-weighted imaging, dynamic contrast-enhanced MRI, and T2-weighted imaging.

OBJECTIVE: The purpose of this study is to evaluate the utility of T2-weighted imaging, dynamic contrast-enhanced MRI (DCE-MRI), and diffusion-weighted imaging (DWI) for detecting prostate cancer in patients with total serum prostate-specific antigen (PSA) levels of 4-10 ng/mL, which is referred to as the "gray zone." MATERIALS AND METHODS: Fifty patients with gray-zone PSA levels underwent MRI before biopsy. According to the sites of biopsy, the prostate was divided into eight regions on MRI scans. These regions were evaluated individually for the following features: detectability of prostate cancer on per-region and per-patient bases, and relationship between tumor size and positive or negative MRI findings for tumor detection. RESULTS: On a per-region basis, the sensitivity and specificity of tumor detection were 36% and 97% for T2-weighted imaging, 43% and 95% for DCE-MRI, 38% and 96% for DWI, and 53% and 93% for the combined method of MRI, respectively. The sensitivity of combined MRI to detect tumor was significantly higher than those of the individual methods (p < 0.001 to p = 0.001). Tumor size was significantly larger in regions with positive MRI findings than in regions with negative MRI findings (p = 0.004). On a per-patient basis, sensitivity and specificity of combined MRI to detect prostate cancer were 83% and 80%, respectively. CONCLUSION: Combined T2-weighted imaging, DWI, and DCE-MRI findings appear to be potentially useful for detecting and managing prostate cancer, even when performed for patients with gray-zone PSA levels.

Locally recurrent prostate cancer after high-dose-rate brachytherapy: the value of diffusion-weighted imaging, dynamic contrast-enhanced MRI, and T2-weighted imaging in localizing tumors.

OBJECTIVE: The purpose of this article is to retrospectively evaluate the utility of prostate MRI for detecting locally recurrent prostate cancer after high-dose-rate (HDR) brachytherapy. MATERIALS AND METHODS: Sixteen men with biochemical failure after HDR brachytherapy for prostate cancer underwent prostate MRI, including T2-weighted imaging, dynamic contrast-enhanced MRI (DCE-MRI), and diffusion-weighted imaging (DWI), using a 1.5-T MRI unit before 12-core-specimen biopsy. Two radiologists in consensus assessed the presence of tumor on each sequence within eight regions of the prostate (six from the peripheral zone [PZ] and two from the transition zone [TZ]) on the basis of biopsy. RESULTS: Biopsy revealed locally recurrent prostate cancer in 22 (17 in PZ and five in TZ) of 128 regions (17.2%). The sensitivity, specificity, and accuracy of each MRI method in the detection of recurrent tumor were 27%, 99%, and 87%, respectively, for T2-weighted imaging; 50%, 98%, and 90%, respectively, for DCE-MRI; and 68%, 95%, and 91%, respectively, for DWI. The sensitivity of DWI in detecting recurrent tumor was significantly higher than that of T2-weighted imaging (p = 0.004). Multiparametric MRI achieved the highest sensitivity (77%) but with slightly decreased specificity (92%). CONCLUSION: These results indicate that a multiparametric MRI protocol that includes DWI provides a sensitive method to detect local recurrence after HDR brachytherapy.

Effects of three types of alpha-1 adrenoceptor blocker on lower urinary tract symptoms and sexual function in males with benign prostatic hyperplasia.

OBJECTIVES: The aim of the present study was to explore the effects of three different types of alpha-1 adrenoceptor blockers (α1-blocker) on lower urinary tract symptoms (LUTS), erectile dysfunction (ED) and ejaculatory dysfunction (EjD) in patients with benign prostatic hyperplasia. METHODS: A total of 136 male LUTS patients aged 50-80 years with International Prostate Symptom Score (IPSS) ≥8 were enrolled. They were divided into three groups. Group S received silodosin at 4 mg twice a day; group T received tamsulosin at 0.2 mg once a day; and group N received naftopidil at 50 mg once a day. Assessment included IPSS, quality of life indexes (QOL), International Index of Erectile Function (IIEF-5), an ejaculation questionnaire, Qmax and post-void residual urine volume (PVR). These parameters were recorded at baseline, and at 1 and 3 months after treatment had ended. RESULTS: Mean IPSS and Qmax significantly improved after treatment in all groups without any significant difference among them. As for the IIEF-5 score, only group N significantly improved at 1 and 3 months. After treatment, 2.6 and 2.4% of patients complained of a de novo reduced volume of ejaculation in both groups T and N, respectively. Ten out of 41 patients (24.4%) complained of a total absence of antegrade ejaculation in group S after treatment. CONCLUSIONS: All three types of α1-blockers provided an objective and subjective improvement of LUTS in the present study population. However, erectile function only improved in patients treated with naftopidil and a higher rate of EjD was observed in those receiving silodosin. Because of their variable effects, we should consider the sexual dimension when prescribing α1-blockers for LUTS.

SERPINE2 is a possible candidate promotor for lymph node metastasis in testicular cancer.

Testicular germ cell tumors (TGCTs) commonly metastasize to the lymph node or lung. However, it remains unclear which genes are associated with TGCT metastasis. The aim of this study was to identify gene(s) that promoted human TGCT metastasis. We intraperitoneally administered conditioned medium (CM) from JKT-1, a cell-line from a human testicular seminoma, or JKT-HM, a JKT-1 cell sub-line with high metastatic potential, into mice with JKT-1 xenografts. Administration of CM from JKT-HM significantly promoted lymph node metastasis. A cDNA microarray analysis showed that JKT-HM cells highly expressed the Serpine peptidase inhibitor, clade E, member 2 (SERPINE2), which encodes a secreted protein. Administration of CM from SERPINE2-silenced JKT-HM cells inhibited lymph node metastasis in the xenograft model, compared with administration of CM from JKT-HM cells. There was no significant difference in xenograft volume. Moreover, administration of CM from SERPINE2-over-expressing JKT-1 was likely to promote lymph node metastasis in the xenograft model. There was no difference in the in vitro proliferation or migration of JKT-1 cells cultured with CM from JKT-HM cells, compared to that with CM from JKT-1. There was no promotion of proliferation or lymphangiogenesis in the xenografts, as measured by Ki-67 and LYVE-1 immunohistochemistry, respectively. Although we could not clarify how SERPINE2 promoted lymph node metastasis, it may be a promoter in the development of lymph node metastasis in the human seminoma cells in a mouse xenograft model.

Apparent diffusion coefficient values in peripheral and transition zones of the prostate: comparison between normal and malignant prostatic tissues and correlation with histologic grade.

PURPOSE: To investigate the utility of apparent diffusion coefficient (ADC) values for discriminating tumor in patients with prostate cancer from normal prostatic tissues in healthy adult men, and to identify correlations between ADC and histologic grade of prostate cancer. MATERIALS AND METHODS: A total of 125 healthy male volunteers (mean age, 60 years; range, 50-86 years) and 90 prostate cancer patients (mean age, 71 years; range, 51-88 years) underwent diffusion-weighted imaging (DWI) of the prostate with a single-shot echo-planar imaging sequence using b-factors of 0 and 800 sec/mm2. ADC was measured from two locations in the peripheral zone (PZ) and two locations in the central gland (CG) in normal subjects, and tumor locations of PZ or transition zone (TZ) in patients with prostate cancer. RESULTS: Mean ADC values of tumor regions in both PZ (1.02+/-0.25x10(-3) mm2/sec) and TZ (0.94+/-0.21x10(-3) mm2/sec) were significantly lower than those in the corresponding normal regions (1.80+/-0.27x10(-3) mm2/sec and 1.34+/-0.14x10(-3) mm2/sec, respectively) (P<0.0001 each). Furthermore, a significant negative correlation was identified between ADC in PZ cancer and tumor Gleason score (rho=-0.497, P<0.0001). CONCLUSION: ADC values appear to provide acceptable diagnostic accuracy in both PZ and TZ.

Ejaculatory dysfunction caused by the new alpha1-blocker silodosin: A preliminary study to analyze human ejaculation using color Doppler ultrasonography.

OBJECTIVES: In order to clinically investigate the mechanism of ejaculatory dysfunction attributable to the alpha1-blocker silodosin, a real-time observation of ejaculation by healthy males was performed. METHODS: Following intake of silodosin, a newly developed selective alpha1-blocker for benign prostatic hypertrophy, ejaculation was dynamically observed using color Doppler ultrasound in three healthy males. Normal ejaculation was also investigated in the same manner. RESULTS: With silodosin intake, no antegrade ejaculation was observed in cases 1 or 2. In case 1, seminal fluid slowly but continuously flowed out from the seminal vesicles into the bladder. In case 2, only a small amount of seminal fluid flowed into the bladder during the ejaculatory sensation. In case 3, ejection of a small amount of semen from the external urethral orifice was observed and inflow of a small amount of seminal fluid into the bladder was also captured. Without silodosin intake, all three subjects exhibited antegrade ejaculation. CONCLUSIONS: The mechanism of ejaculatory dysfunction is intricately related to retrograde ejaculation (retrograde inflow of seminal fluid), insufficient contraction of the seminal vesicles, and insufficient rhythmic contraction of the muscles of the pelvic floor.

Prostate cancer: relationships between postbiopsy hemorrhage and tumor detectability at MR diagnosis.

PURPOSE: To retrospectively evaluate the influence of postbiopsy hemorrhage on the accuracy of tumor detection at T2-weighted magnetic resonance (MR) imaging, dynamic contrast material-enhanced MR imaging, and diffusion-weighted (DW) MR imaging of prostate cancer, with histologic findings as the reference standard. MATERIALS AND METHODS: The institutional review board approved this study and waived the requirement for informed consent. Forty male patients aged 62-84 years (mean age, 71 years) who had prostate cancer underwent MR imaging of the prostate gland after ultrasonographically (US) guided systematic 12-core-specimen biopsy. The mean time between biopsy and MR imaging was 24 days (range, 6-54 days). T1-weighted, T2-weighted, dynamic contrast-enhanced, and DW imaging examinations were performed at 1.5 T. The prostate was divided, according to the biopsy sites, into eight regions on the MR images. Three reviewers in consensus evaluated each region for hemorrhage and prostate cancer. Statistical evaluations were performed with Mann-Whitney U, Ryan, and Spearman rank correlation tests. RESULTS: Intraglandular hemorrhage was observed in 38 (95%) patients and significantly more often in the peripheral zone (PZ) than in the transition zone (TZ) (P < .001). Degree of hemorrhage did not correlate significantly (P = .536) with time between biopsy and MR imaging. The sensitivity, specificity, and accuracy of combined T2-weighted, dynamic contrast-enhanced, and DW imaging in the diagnosis of prostate cancer were 69%, 85%, and 78%, respectively. Sensitivity and specificity were lower for the TZ than for the PZ. Degree of hemorrhage was significantly lower in regions of positive biopsy findings than in regions of negative biopsy findings (P = .001) and correlated negatively with tumor size (P = .043). CONCLUSION: Interpretation of combined T2-weighted, dynamic contrast-enhanced, and DW MR image findings can yield reasonable diagnostic accuracy in both the PZ (80% [191 of 240 regions]) and the TZ (74% [59 of 80 regions]).

Optimal approach for prostate cancer detection as initial biopsy: prospective randomized study comparing transperineal versus transrectal systematic 12-core biopsy.

OBJECTIVES: Transperineal and transrectal prostate biopsy are both used for prostate cancer detection. However, which approach is superior remains unknown. In this study, we performed a prospective randomized study to compare the efficacy of transperineal versus transrectal 12-core initial prostate biopsy. METHODS: From May 2003 to October 2005, a prospective randomized study of transperineal versus transrectal 12-core biopsy (126 and 120 patients, respectively) was conducted in 246 patients with a prostate-specific antigen level of 4.0 to 20.0 ng/mL. All procedures were performed with the patient in the lithotomy position, with the transperineal and transrectal approach performed with spinal anesthesia (0.5% bupivacaine) or a caudal block (1% lidocaine), respectively. With both approaches, eight biopsy specimens were obtained systematically from the peripheral zone, including the apex, and four from the transition zone. RESULTS: The cancer detection rate was 42.1% (53 of 126 patients) with the transperineal approach and 48.3% (58 of 120 patients) with the transrectal approach (P = 0.323). For all patients undergoing transperineal and transrectal biopsy, the cancer core rate (cancer core number/biopsy core number) was 13.7% (207 of 1512 cores) and 14.4% (208 of 1440 cores), respectively (P = 0.566). Apart from headache, presumably related to the spinal anesthesia, no significant differences were found in the complications between the two groups. CONCLUSIONS: No significant differences were found in the cancer detection rate, cancer core rate, or complications between the two approaches. We believe that the preferred approach as an initial prostate biopsy is the transrectal approach, which does not require spinal anesthesia or another burdensome process.

Age-related and zonal anatomical changes of apparent diffusion coefficient values in normal human prostatic tissues.

PURPOSE: To identify age-related changes and differences in the diffusion of water molecules within the prostate, through diffusion-weighted imaging (DWI) of the prostate gland in healthy adult Japanese men. MATERIALS AND METHODS: A total of 114 healthy male volunteers (mean age, 55 years; range, 24-81 years) underwent DWI of the prostate with a single-shot echo-planar imaging (EPI) sequence using b-factors of 0 and 1000 seconds/mm(2). Apparent diffusion coefficient (ADC) values of six locations in the peripheral zone (PZ) and two locations in the central gland (CG) were measured and correlations between region and age were examined. RESULTS: ADC values measured within both PZ and CG regions of the prostate showed a uniform distribution, and no significant differences were found between evaluated regions. However, mean ADC values were 1.64 +/- 0.27 x 10(-3) mm(2)/second for PZ and 1.26 +/- 0.12 x 10(-3) mm(2)/second for CG, representing a significant difference. In addition, significant positive correlations were identified between ADC values for both PZ and CG regions and subject age (r = 0.526, P < 0.0001; r = 0.190, P = 0.0431, respectively). CONCLUSION: ADC values within both PZ and CG regions of the prostate increase with age, and this must be taken into consideration when using DWI in the diagnosis of prostate cancer.

Hydronephrosis caused by intra-abdominal abscess from cecal perforation by an ingested fish bone.

A patient was treated for hydronephrosis caused by an intra-abdominal abscess arising from cecal perforation by an ingested fish bone. To the authors' knowledge there is no previous report of such ureteral obstruction. Ureteral stenting, drainage of the abscess, and ileocecal resection were performed. Six months of stenting were required to attain ongoing ureteral patency following removal.

Transperineal extended biopsy improves the clinically significant prostate cancer detection rate: a comparative study of 6 and 12 biopsy cores.

BACKGROUND: We evaluated the improvement in the rate of prostate cancer detection when using a 12-core transperineal biopsy protocol including transitional zone biopsy. METHODS: Between April 2003 and November 2004, 247 consecutive men underwent transperineal systemic 12-core biopsy of the prostate. Six cores were obtained at the peripheral zone, four at the transitional zone and two at the apex. We examined the cancer detection rate in each of the 12 cores, and also determined the improvement of cancer detection resulting from the extensive 12-core versus standard 6-core biopsy. RESULTS: Using the extensive 12-core biopsy, prostate cancer was detected in 98 cases (39.7%). Prostate-specific antigen (PSA), PSA density, the positive rate in digital rectal examination and transrectal ultrasound findings were significantly higher in the prostate cancer group than in the non-prostate cancer group, and prostate volume was larger in non-prostate cancer group. Every site showed almost the same positive rate, between 17.8 and 21.5%. There were 20 cases which were positive in the extended biopsy, but negative in the sextant. The detection improved significantly (20.4%). The improvement of cancer detection in extended biopsy was better in men with PSA levels of 10 ng/mL or less (28.9%), PSA density 0.3 or less (25.8%), negative digital rectal examination (23.3%), and negative transrectal ultrasound (21.6%). Of these twenty patients, no cases with insignificant tumor were detected in the six prostatectomy cases. In particular, three cases of the six were transitional-zone-only cancer. CONCLUSION: Transperineal extended 12-core biopsy including 4 transitional zone cores is a more useful procedure than transperineal 6-core biopsy. Routine transitional zone biopsy, that is different from transrectal biopsy, might be useful for detecting biologically significant cancer.