[CLINICAL STUDY OF SEQUENTIAL THERAPY WITH ABIRATERONE AND ENZALUTAMIDE FOLLOWING DOCETAXEL THERAPY FOR CASTRATION-RESISTANT PROSTATE CANCER].

(Purpose) This study is to evaluate the efficacy and safety of sequential therapy with two novel drugs, abiraterone and enzalutamide after docetaxel (DOC) therapy for castration-resistant prostate cancer (CRPC). (Material and methods) Twenty-one patients were identified received sequential therapy with abiraterone and enzalutamide after DOC therapy at our institution. We investigated PSA response (decrease of 50% or more) to prior administered drug as primary endpoint, and overall survival rate and occurrence of adverse events as secondary endpoint. (Results) There were 12 patients in the group preliminarily administered enzalutamide (Group E) and 9 patients in the group preliminarily administered abiraterone (Group A). The novel drugs were administered immediately following DOC therapy in nearly all cases. Of the 9 patients in Group A, only one patient (11%) and of the 12 patients in Group E, only one patient (9%) achieved PSA decrease of 50% or more, thus resulting in a poor response rate. There was not significantly difference in both groups. The overall survival rates of Group A and E were not significantly difference. There were three adverse events which required change drug. Those were two cases (appetite loss and general fatigue) on enzalutamide and one case (edema) on abiraterone. (Conclusion) This study suggested that sequential therapy with abiraterone and enzalutamide after DOC therapy had poor clinical benefit regardless of the order of administration of both drugs.

Extracapsular extension of prostate cancer: diagnostic value of combined multiparametric magnetic resonance imaging and isovoxel 3-dimensional T2-weighted imaging at 1.5 T.

OBJECTIVE: The objective of this study was to assess whether adding isovoxel 3-dimensional T2-weighted imaging (volume isotropic T2-weighted acquisition [VISTA]) to multiparametric magnetic resonance imaging (mp-MRI) improves the ability to diagnose the extracapsular extension (ECE) of prostate cancer. METHODS: Two radiologists independently evaluated ECE on images acquired with mp-MRI only (method A) and mp-MRI plus VISTA (method B) in 50 men who had undergone prostatectomy. We also compared the signal-to-noise ratio of the tumor on T2WI and VISTA scans. RESULTS: Sensitivity, specificity, and accuracy were higher with method B. For both readers, specificity, accuracy, and the area under the receiver operating characteristic curve of method B were significantly higher than those of method A (reader 1: P = 0.028, 0.025, and 0.006; reader 2: P = 0.017, 0.0071, and 0.018). The signal-to-noise ratio was significantly higher on T2-weighted imaging than VISTA images (9.21 [SD, 2.46] vs 7.30 [SD, 1.87], P < 0.01). CONCLUSIONS: The addition of VISTA to mp-MRI improves the diagnostic value for ECE significantly.

Clinical utility of the normalized apparent diffusion coefficient for preoperative evaluation of the aggressiveness of prostate cancer.

PURPOSE: Normalization of the apparent diffusion coefficient (ADC) may overcome ADC variability attributable to different patient and/or technical factors. The purpose of this study was to compare the efficacy of ADC and the normalized ADC (nADC) for differentiating between prostate cancer with a Gleason score (GS) = 6 and GS > 6 and to identify an optimum reference for nADC calculations. MATERIALS AND METHODS: Our study population comprised 58 patients who underwent diffusion-weighted MRI followed by radical prostatectomy. The nADC of the prostate cancer was calculated as ADC (cancer)/ADC (reference) by using the obturator internus muscle, urine in the bladder, and a 20-ml saline bottle placed on the groin as references. We performed receiver operating characteristic (ROC) analysis to identify the optimum reference for nADC calculations. RESULTS: To differentiate between GS = 6 and GS > 6 prostate cancer, the area under the ROC curve of the nADC obtained with a saline bottle as reference was best (0.85) and significantly better than the area under the ADC ROC curve (0.71). CONCLUSIONS: nADC is superior to ADC for estimating the aggressiveness of prostate cancer. It is a noninvasive technique that aids in the selection of appropriate treatments.

Triage of low-risk prostate cancer patients with PSA levels 10 ng/ml or less: comparison of apparent diffusion coefficient value and transrectal ultrasound-guided target biopsy.

OBJECTIVE: The purpose of our study was to identify low-risk prostate cancer on the basis of the D'Amico clinical risk score in patients with prostate-specific antigen (PSA) levels 10 ng/mL or less who had undergone radical prostatectomy by comparing apparent diffusion coefficient (ADC) with transrectal ultrasound (TRUS)-guided target biopsy. MATERIALS AND METHODS: In the preliminary study, we used receiver operating characteristic (ROC) analysis and determined the cutoff ADC to identify prostate cancer with a Gleason score of 6 or less for 117 patients. In the primary study, we assessed the combination of routine MRI (T2-weighted and diffusion-weighted imaging) plus the cutoff ADC value ("method A") to identify low-risk prostate cancer for another 89 patients. Their diagnostic value was compared with that of routine MRI combined with the Gleason score obtained from TRUS-guided target biopsies ("method B"). RESULTS: The preliminary study showed that a mean ADC of 1.04 × 10(-3) mm(2)/s was the best cutoff. In the primary study, accuracy was statistically higher with method A for each reader (p = 0.041). CONCLUSION: In patients with PSA levels 10 ng/mL or less, the combination of MRI findings plus the cutoff ADC is significantly more accurate for the identification of low-risk prostate cancer than is the combination of MRI followed by TRUS-guided target biopsy.

[Clinical study of long-term docetaxel based chemotherapy treatment for patients with castration-resistant prostate cancer].

PURPOSE: To evaluate long-term continuous administration of docetaxel (DOC), over survival rate, PSA level and adverse effects were analyzed, retrospectively. We also compared the results of long-term treatment group and short-term treatment group. MATERIAL AND METHODS: This study reported that 14 cases of long-term continuous administration of DOC consisting of 11 or more cycles among 51 patients of castration-resistant prostate cancer (CRPC) treated with DOC from October 2008 to September 2013 at our institution, retrospectively. Nineteen patients who had treated with DOC 10 or less cycles were defined as short-term dose group, and both groups were compared. DOC was administered every 3 to 4 weeks at 60 to 70 mg/m2, and was treated with prednisolone at 10 mg/day as a general. RESULTS: The median number of treatment cycles was 15. Thirteen cases showed a decrease in PSA levels and 10 cases showed a decrease in PSA levels of 50% or more, the 1-year survival rate of long-term dose and short-term dose group were 100% and 16%. Adverse effects of grade 3 or lower consisted of leukocytopenia in 85% and thrombocytopenia in 28%, however, grade 4 or higher were not observed in long-term dose group. In multivariable analysis of parameters, long-term treatment was related to PSA levels at start of treatment and ALP levels. CONCLUSION: Forty-two percent of patients who have CRPC at our institution undergo long-term DOC based chemotherapy treatment It may be suggested that long-term DOC based chemotherapy for some cases contribute to extend survival time with no serious adverse events.

Ultra-high-b-value diffusion-weighted MR imaging for the detection of prostate cancer: evaluation in 201 cases with histopathological correlation.

PURPOSE: To assess the diagnostic performance of diffusion-weighted magnetic resonance (MR) imaging (DWI) for prostate cancer detection, using different b-values. METHODS: A total of 201 patients who underwent MR imaging before total prostatectomy were evaluated. MR images were independently assessed by three radiologists. Three combinations of sequences were separately evaluated, as follows: group 1 [T2-weighted images (T2WI) alone], group 2 (T2WI and DWI with a b-value of 1,000 s/mm2), group 3 (T2WI and DWI with a b-value of 2,000 s/mm2). Whole-mount-section histopathological examination was the reference standard. Areas under the receiver operating characteristic curve (AUCs) and diagnostic performance parameters were determined. RESULTS: The sensitivity, specificity, and AUC for the detection of prostate cancer were as follows: 52.2%, 80.7%, and 0.694 in group 1; 61.2%, 82.6%, and 0.755 in group 2; 73.2%, 89.7%, and 0.842 in group 3. Group 3 achieved the highest diagnostic performance, followed by group 2 (P<0.05). In the transition zone, the specificity was lower (P<0.001) for group 2 (82.2%) than for group 1 (86.2%). CONCLUSION: The addition of diffusion-weighted images with a b-value of 2,000 s/mm2 to T2WI can improve the diagnostic performance of MR imaging in prostate cancer detection.

[Evaluation of immediate androgen deprivation adjuvant therapy in patients with lymph node positive prostate cancer after radical prostatectomy and pelvic lymphadenectomy].

PURPOSE: We assessed the outcome after radical prostatectomy and pelvic lymphadenectomy for lymph node positive prostate cancer retrospectively. Furthermore, we compared the efficacy of immediate androgen deprivation adjuvant therapy in node positive patients who have undergone radical prostatectomy. MATERIAL AND METHODS: We investigated 62 patients who have undergone radical prostatectomy and pelvic lymphadenectomy and have been found to have lymph node positive prostate cancer at our facility between January 1992 and January 2008. We researched the clinical stages, the pathological stages and Gleason scores for pathological pN1 + prostate cancer, retrospectively. The serum PSA levels were followed up every 6 months, and we considered that biochemical progression was PSA >0.4 ng/ml. We classified the groups treated with or without immediate androgen deprivation adjuvant therapy, the biochemical progression free survival and cause specific survival were analyzed by the Kaplan-Meier method, and the statistical significance was determined by the log rank test. RESULTS: The rate of lymph node positive patients who have undergone radical prostatectomy was 7.1%. The rate of 8 or greater in Gleason score of all the lymph node positive patients was 68.3%. The 5-year prostate cancer specific survival and 5-year biochemical progression free survival rates were 90.3 and 67.4% of all the patients. The biochemical progression free survival rate of the group of patients who have received immediate androgen deprivation therapy after radical prostatectomy was significantly higher than that of the group of patients who have not received immediately androgen deprivation therapy. CONCLUSION: It may be suggested that early androgen deprivation adjuvant therapy benefits patients with nodal metastases who have undergone radical prostatectomy and lymphadenectomy, compared with those who received deferred treatment, although in a retrospective nonrandomized study.