Real-world data on the comprehensive genetic profiling test for Japanese patients with metastatic castration-resistant prostate cancer.

OBJECTIVE: comprehensive genomic profiling test has been covered by Japanese health insurance since June 2019. However, no real-world data on the test have been reported with a focus on Japanese patients with prostate cancer. METHODS: we retrospectively reviewed the data of 45 consecutive patients with metastatic castration-resistant prostate cancer, who underwent the comprehensive genomic profiling tests at Kitasato University Hospital between August 2019 and December 2022. Patients' characteristics, prevalence of gene alterations and therapeutic impact of genotype-matched therapy were assessed. RESULTS: genomic data were obtained using a tissue-based test (n = 32) and liquid-based test (n = 13). Actionable genomic alternations were identified in 51.1% of patients, and 22.2% were treated with genotype-matched therapy. The main reason for not receiving genotype-matched therapy was disease progression, accounting for 46.2% (6/13). Kaplan-Meier analysis showed significantly longer overall survival after the comprehensive genomic profiling tests in patients with genotype-matched therapy under public insurance (17.8%, n = 8) than those without it (median: not reached vs. 18.1 months; P = 0.003). Five (62.5%) out of the eight patients with genotype-matched therapy under public insurance had BRCA1 or 2 deleterious alteration. Multivariate analyses showed that BRCA deleterious alteration (17.8%, n = 8) was an independent risk factor for shorter time to castration-resistant prostate cancer (hazard ratio: 2.46, 95% confidence interval: 1.04-5.87; P = 0.041), and no patients with the alteration had ≤5 bone metastases. CONCLUSIONS: the results of this study showed the promising survival outcomes in patients with genotype-matched therapy under public insurance, even in the castration-resistant prostate cancer setting. Further detection of promising therapeutic target gene is expected to increase the number of patients who reach genotype-matched therapies.

Dosimetric Predictors of Toxicity after Prostate Stereotactic Body Radiotherapy: A Single-Institutional Experience of 145 Patients.

The indications for stereotactic body radiotherapy (SBRT) for prostate cancer have increased. However, the relationships between adverse events and risk factors remain unclear. This study aimed to clarify associations between adverse events and dose index for prostate SBRT. Participants comprised 145 patients irradiated with 32-36 Gy in 4 fractions. Radiotherapy-related risk factors such as dose-volume histogram parameters and patient-related risk factors such as T stage and Gleason score were evaluated in a competing risk analysis. Median follow-up duration was 42.9 months. A total of 9.7% had acute Grade ≥ 2 GU toxicities and 4.8% had acute Grade ≥ 2 GI toxicities. A total of 11.1% had late Grade ≥ 2 GU toxicities and 7.6% had late Grade ≥ 2 GI toxicities. Two (1.4%) patients suffered from late Grade 3 GU toxicities. Similarly, two (1.4%) patients suffered from late Grade 3 GI toxicities. Acute GU and GI events correlated with prostate volume and dose to the hottest 10 cc volume (D10cc)/volumes receiving a minimum of 30 Gy (V30 Gy) of rectum, respectively. Late GI toxicity, frequency, and rectal hemorrhage correlated with rectal D0.1 cc/D1 cc, maximum dose to the bladder, and rectal D0.1 cc, respectively. Toxicities after prostate SBRT using 32-36 Gy/4 fractions were acceptable. Our analysis showed that acute toxicities correlated with volume receiving a medium dose level, and late toxicities correlated with highest point dose of organs at risk.

Case Reports of Transdermal Fentanyl Patch Administration Difficulties in Cancer Patients with Excess Sweating.

(Case 1) A 45-year-old male was diagnosed with prostate cancer. Treatment was administered using bicalutamide and leuprorelin acetate, while a transdermal fentanyl (TDF) was applied for pain relief. However, TDF continued to peel off owing to excessive sweating, even when reinforced by a protective layer. As such, TDF was discontinued and pain control was initiated using other medicines. Sweating occurred irregularly because of hot flashes, approximately four to five times per day. (Case 2) A 37-year-old male was diagnosed with a malignant thymoma and sacral metastasis. For analgesic control, etodolac tablets, carbamazepine tablets, and TDF were administered. Subsequently, the dose of the TDF was gradually increased, but the analgesic effect was low; thus, fentanyl blood concentration was measured. The measurements showed that even higher TDF doses did not increase fentanyl blood levels. During this period, full body sweating began to occur to a large extent due to unknown causes, and it was thought that the absorption of fentanyl decreased. When using a TDF, it is necessary to monitor patients for any sweating during treatment, while also considering changes in medication in some cases. This should promote the maintenance and improvement of the quality of life of the affected patients.

Comparative effectiveness of low-dose-rate brachytherapy with or without external beam radiotherapy in favorable and unfavorable intermediate-risk prostate cancer.

We compared clinical outcomes associated with seed brachytherapy (SEED-BT) alone and SEED-BT plus external-beam radiotherapy (EBRT) for intermediate-risk prostate cancer using propensity score-matched analysis. From 2006 to 2011, 993 patients diagnosed with intermediate-risk were treated with either SEED-BT alone (n = 775) or SEED-BT plus EBRT (n = 158) at 3 tertiary hospitals. In the propensity score-matched analysis (102 pairs), median follow-up was 95 months (range 18-153 months). The 8-year biochemical recurrence-free rate (bRFR) was significantly better with SEED-BT alone than with combined radiotherapy (93.3% vs. 88.4%; HR 0.396; 95% CI 0.158-0.991). Grade 2 or greater late genitourinary toxicities were significantly fewer with SEED-BT alone than with combined radiotherapy (21.0% vs. 33.2%; HR 0.521; 95% CI 0.308-0.881). Similarly, grade 2 or greater late gastrointestinal toxicities were significantly fewer with SEED-BT alone (0% vs. 12.2%; HR 0.125; 95% CI 0.040-0.390). For the unfavorable intermediate-risk subgroups, SEED-BT alone yielded a significantly better bRFR than the combined radiotherapy (HR 0.325; 95% CI 0.115-0.915). SEED-BT alone might be a better disease-management plan than SEED-BT plus EBRT for intermediate-risk prostate cancer regardless of favorable and unfavorable characteristics.

Cancer-specific and net overall survival in older patients with de novo metastatic prostate cancer initially treated with androgen deprivation therapy.

OBJECTIVE: This study aimed to assess survival outcomes in older patients with de novo metastatic prostate cancer who initially received androgen deprivation therapy. METHODS: The retrospective multicenter study included 2784 men with metastatic prostate cancer who were treated with androgen deprivation therapy between 2008 and 2017. Patients were classified into <75, 75-79, and ≥80 age groups. Propensity score matching was conducted to assess the cancer-specific survival of the groups. The 5-year net overall survival of each group was derived to evaluate relative survival compared with the general population using the Pohar-Perme estimator and the 2019 Japan Life Table. RESULTS: During the follow-up (median, 34 months), 1014 patients died, of which 807 died from metastatic prostate cancer progression. Compared with the <75 group, the cancer-specific survival of the 75-79 group was similar (hazard ratio 1.07; 95% confidence interval 0.84-1.37; P = 0.580), whereas that of the ≥80 group was significantly worse (hazard ratio 1.41; 95% confidence interval 1.10-1.80; P = 0.006). The 5-year net overall survival of the <75, 75-79, and ≥80 age groups were 0.678, 0761, and 0.718, respectively. The 5-year net overall survival of patients aged ≥80 years with low- and high-volume disease were 0.893 and 0.586, respectively, which was comparable with those in patients aged <75 years (0.872 and 0.586, respectively). CONCLUSIONS: Older metastatic prostate cancer patients aged ≥80 years had poorer cancer-specific survival compared with younger patients. Conversely, 5-year net overall survival in older patients aged ≥80 years was comparable with that in younger patients aged <75 years.

Direct comparison of low-dose-rate brachytherapy versus radical prostatectomy using the surgical definition of biochemical recurrence for patients with intermediate-risk prostate cancer.

BACKGROUND: We compared the oncological outcomes of patients who received seed brachytherapy (SEED-BT) with those who received radical prostatectomy (RP) for intermediate-risk prostate cancer. METHODS: Candidates were patients treated with either SEED-BT (n = 933) or RP (n = 334). One-to-one propensity score matching was performed to adjust the patients' backgrounds. We compared the biochemical recurrence (BCR)-free rate using the Phoenix definition (prostate-specific antigen [PSA] nadir plus 2 ng/mL) for SEED-BT and the surgical definition (PSA cut-off value of 0.2 ng/mL) for RP. We also directly compared the BCR-free rates using the same PSA cut-off value of 0.2 ng/mL for both SEED-BT and RP. RESULTS: In the propensity score-matched analysis with 214 pairs, the median follow-up treatment was 96 months (range 1-158 months). Fifty-three patients (24.7%) were treated with combined SEED-BT and external-beam radiotherapy. Forty-three patients (20.0%) received salvage radiotherapy after RP. Comparing the BCR-free rate using the above definitions for SEED-BT and RP showed that SEED-BT yielded a significantly better 8-year BCR-free rate than did RP (87.4% vs. 74.3%, hazard ratio [HR] 0.420, 95% confidence interval [CI] 0.273-0.647). Comparing the 8-year BCR-free rate using the surgical definition for both treatments showed no significant difference between the two treatments (76.7% vs. 74.3%, HR 0.913, 95% CI 0.621-1.341). SEED-BT had a significantly better 8-year salvage hormonal therapy-free rate than did RP (92.0% vs. 85.6%, HR 0.528, 95% CI 0.296-0.942, P = 0.030). The 8-year metastasis-free survival rates (98.5% vs. 99.0%, HR 1.382, 95% CI 0.313-6.083, P = 0.668) and overall survival rates (91.9% vs. 94.6%, HR 1.353, 95% CI 0.690-2.650) did not significantly differ between the treatments. CONCLUSIONS: The BCR-free rates did not significantly differ between patients treated with SEED-BT and those treated with RP for intermediate-risk prostate cancer even when they were directly compared using the surgical definition for BCR. SEED-BT and RP can be adequately compared for oncological outcomes.

Efficacy of combined androgen blockade therapy in patients with metastatic hormone-sensitive prostate cancer stratified by tumor burden.

OBJECTIVE: To determine the effect of combined androgen blockade with a first-generation anti-androgen on the prognoses of metastatic hormone-sensitive prostate cancer patients stratified by tumor burden. METHODS: We retrospectively analyzed the cases of metastatic hormone-sensitive prostate cancer patients who were treated with androgen deprivation therapy in 2008-2017 at 30 institutions in Japan. To compare the overall survival and progression-free survival rates of the patients treated with castration monotherapy and combined androgen blockade, we carried out a Cox proportional hazards regression analysis using both inverse probability of treatment weighting and instrumental variables methods. High-burden disease was defined as the presence of four or more bone metastases and/or visceral metastasis. RESULTS: Of 2048 patients, 702 (34.3%) and 1346 (65.7%) patients were classified as the low- and high-burden groups, respectively. In each group, >80% of the patients were treated with combined androgen blockade. Although there was no significant between-group difference in the overall survival according to the androgen deprivation therapy method, in the high-burden group the progression-free survival of the combined androgen blockade-treated patients was significantly better than that of patients treated with castration monotherapy: inverse probability of treatment weighting method, hazard ratio 0.49, 95% confidence interval 0.34-0.71; instrumental variables method, hazard ratio 0.80, 95% confidence interval 0.60-0.98. CONCLUSION: In the high-burden group, combined androgen blockade with a first-generation anti-androgen resulted in superior progression-free survival compared with castration monotherapy. For well-selected metastatic hormone-sensitive prostate cancer patients, the use of combined androgen blockade might still have some suitable scenarios.

Management of patients with advanced prostate cancer in Japan: 'real-world' consideration of the results from the Advanced Prostate Cancer Consensus Conference.

A multidisciplinary approach is necessary to manage advanced prostate cancer. The Advanced Prostate Cancer Consensus Conference (APCCC) in 2019 provided a practical guide to help clinicians consider therapeutic options in controversial areas, but healthcare systems vary across the world. At the 109th annual meeting of the Japanese Urological Association in December 2021, Japanese urologists voted on the questions in the APCCC 2019 guidelines regarding prostate-specific membrane antigen-positron emission tomography (PSMA-PET), management of oligometastatic prostate cancer, management of nonmetastatic castration-resistant prostate cancer (CRPC), management of a primary tumor in metastatic settings, systemic treatment of newly diagnosed metastatic castration-sensitive prostate cancer (CSPC), management of metastatic CRPC (mCRPC), and tumor genomic testing. We summarize the "real-world" status of the management of advanced prostate cancer in Japan. Several differences were noted in the management of advanced prostate cancer between Japanese urologists and the APCCC 2019 guidelines. Many Japanese urologists chose conventional imaging modalities for detecting metastasis instead of PSMA-PET. More Japanese urologists prefer androgen-deprivation therapy (ADT) alone in the management of low-volume metastatic CSPC than the APCCC panelists do, In the management of M0 CRPC, darolutamide and enzalutamide were chosen more by Japanese urologists than by the voters at the APCCC 2019. Bicalutamide remains one of the options for the management of mCRPC in Japan. More Japanese urologists do not recommend microsatellite instability (MSI) and BRCA1/2 tests than the voters at the APCCC 2019. Clinical evidence in Japan should be collected to address these discrepancies.

Cytopathic effects and local immune responses in repeated neoadjuvant HSV-tk + ganciclovir gene therapy for prostate cancer.

OBJECTIVE: Cytopathic effects and local immune response were analyzed histologically in prostatic cancer (PCa) with in situ herpes simplex virus-thymidine kinase (HSV-tk)/ganciclovir (GCV) gene therapy (GT). METHODS: Four high-risk PCa patients who received HSV-tk/GCV GT were investigated. After two cycles of intraprostatic injection of HSV-tk and administration of GCV, radical prostatectomy was performed. Formalin-fixed, paraffin-embedded sections were evaluated using immunohistochemistry. PCa with hormone therapy (HT, n=3) or without neoadjuvant therapy (NT, n=4) that were equivalent in terms of risk were also examined as reference. Immunoreactively-positive cells were counted in at least three areas in cancer tissue. Labeling indices (LI) were calculated as percentage values. RESULTS: ssDNA LI in GT increased, indicating apoptosis, as well as tumor-infiltrating lymphocytes and CD68-positive macrophages, compared with their biopsies. GT cases showed significantly higher numbers of single-stranded DNA (ssDNA) LI, CD4/CD8-positive T cells and CD68-positive macrophages including M1/M2 macrophages than HT or NT cases. However, there was no significant difference in CD20-positive B cells among the types of case. There were strong correlations between CD8+ T cells and CD68+ macrophages (ρ=0.656, p<0.0001) as well as CD4+ T cells and CD20+ B cells (ρ=0.644, p<0.0001) in PCa with GT. CONCLUSIONS: Enhanced cytopathic effect and local immune response might be indicated in PCa patients with HSV-tk/GCV gene therapy.

Effect of cisplatin on metastatic castration-resistant prostate cancer with BRCA2 mutation: A case report.

Poly (ADP-ribose) polymerase inhibitors exhibit strong activity for treating the DNA damage repair defect in patients with prostate carcinoma (PCa). Although conventional DNA-damaging agents can theoretically lead to synthetic antitumoral effects, no report has clearly mentioned the clinical use of cisplatin for treating PCa patients with the breast cancer gene (BRCA)2 mutation. We administered 80 mg/m2 cisplatin triweekly to a patient with metastatic castration-resistant PCa (mCRPC) with the BRCA2 mutation, and after ten cycles, the prostate-specific antigen was dramatically decreased. We suggest that BRCA2 mutations may indicate the use of cisplatin for treating patients with mCRPC.

Novel metastatic burden-stratified risk model in de novo metastatic hormone-sensitive prostate cancer.

The metastatic burden is a critical factor for decision-making in the treatment of metastatic hormone-sensitive prostate cancer (HSPC). This study aimed to develop and validate a novel risk model for survival in patients with de novo low- and high-burden metastatic HSPC. The retrospective observational study included men with de novo metastatic prostate cancer who were treated with primary androgen-deprivation therapy at 30 institutions across Japan between 2008 and 2017. We created a risk model for overall survival (OS) in the discovery cohort (n = 1449) stratified by the metastatic burden (low vs high) and validated its predictive ability in a separate cohort (n = 951). Based on multivariate analyses, lower hemoglobin levels, higher Gleason grades, and higher clinical T-stage were associated with poor OS in low-burden disease. Meanwhile, lower hemoglobin levels, higher Gleason grade group, liver metastasis, and higher extent of disease scores in bone were associated with poor OS in patients with high-burden disease. In the discovery and validation cohorts, the risk model using the aforementioned parameters exhibited excellent discriminatory ability for progression-free survival and OS. The predictive ability of this risk model was superior to that of previous risk models. Our novel metastatic burden-stratified risk model exhibited excellent predictive ability for OS, and it is expected to have several clinical uses, such as precise prognostic estimation.

A novel prognostic model for Japanese patients with newly diagnosed bone-metastatic hormone-naïve prostate cancer.

Objectives: To evaluate the prognosis of newly diagnosed patients with metastatic hormone-naïve prostate cancer (mHNPC) and develop a novel prognostic model based on ChemoHormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer (CHAARTED) risk classifications. Patients and methods: We retrospectively analyzed the data of 578 newly diagnosed mHNPC patients initially treated with androgen deprivation therapy. We evaluated three clinical factors, namely, CHAARTED risk classifications (high-volume disease [HVD] vs low-volume disease [LVD]), Gleason scores (GS, 9-10 vs ≤8), and hemoglobin (Hb, ≤13.0 g/dL vs >13.0 g/dL), for their prognostic potential in predicting time to castration-resistant prostate cancer (TTC) and overall survival (OS) of mHNPC patients by multivariate analysis. Moreover, we developed a novel prognostic model that consisted of significant prognostic factors. Results: Of the entire cohort, the median TTC and OS values were 18.3 and 67.5 months, respectively. HVD, GS 9-10, and Hb ≤13.0 g/dL were independent poor prognostic factors for both TTC and OS. We developed a novel prognostic model which could stratify mHNPC patients into four risk groups according to the numbers of poor prognostic factors: group 1, LVD with low-risk (LVD patients without GS 9-10 and Hb ≤13.0 g/dL); group 2, LVD with high-risk (LVD patients with GS 9-10, Hb ≤13.0 g/dL, or both); group 3, HVD with low-risk (HVD patients without GS 9-10 with or without Hb ≤13.0 g/dL); and group 4, HVD with high-risk (HVD patients with GS 9-10 with or without Hb ≤13.0 g/dL). The median TTC and OS of groups 1, 2, 3, and 4 were 124.8, 36.4, 17.9, and 11.2 months, and 117.2, 94.2, 67.9, and 46.2 months, respectively. A significant difference in TCC and OS was found between all groups. Conclusion: We developed a prognostic model for mHNPC patients that consisted of CHAARTED risk classifications, GS, and Hb. Our prognostic model could significantly stratify the prognosis of patients with LVD and HVD into two groups each. This model might be a good reference for shared decision making between patients and physicians on the initial treatment for mHNPC.

Efficacy and safety of darolutamide in Japanese patients with nonmetastatic castration-resistant prostate cancer: a sub-group analysis of the phase III ARAMIS trial.

BACKGROUND: Darolutamide, an oral androgen receptor inhibitor, has been approved for treating nonmetastatic castration-resistant prostate cancer (nmCRPC), based on significant improvements in metastasis-free survival (MFS) in the ARAMIS clinical trial. Efficacy and safety of darolutamide in Japanese patients are reported here. METHODS: In this randomized, double-blind, placebo-controlled phase III trial, 1509 patients with nmCRPC and prostate-specific antigen (PSA) doubling time ≤ 10 months were randomized 2:1 to darolutamide 600 mg twice daily or matched placebo while continuing androgen deprivation therapy. The primary endpoint was MFS. RESULTS: In Japan, 95 patients were enrolled and randomized to darolutamide (n = 62) or placebo (n = 33). At the primary analysis (cut-off date: September 3, 2018), after 20 primary end-point events had occurred, median MFS was not reached with darolutamide vs. 18.2 months with placebo (HR 0.28, 95% CI 0.11-0.70). Median OS was not reached due to limited numbers of events in both groups but favored darolutamide in the Japanese subgroup. Time to pain progression, time to PSA progression, and PSA response also favored darolutamide. Among Japanese patients randomized to darolutamide vs. placebo, incidences of treatment-emergent adverse events (TEAEs) were 85.5 vs. 63.6%, and incidences of treatment discontinuation due to TEAEs were 8.1 vs. 6.1%. CONCLUSIONS: Efficacy outcomes favored darolutamide in Japanese patients with nmCRPC, supporting the clinical benefit of darolutamide in this patient population. Darolutamide was well tolerated; however, due to the small sample size, it is impossible to conclude with certainty whether differences in the safety profile exist between Japanese and overall ARAMIS populations.

Differential prognostic factors in low- and high-burden de novo metastatic hormone-sensitive prostate cancer patients.

Metastatic burden is a critical factor for therapy decision-making in metastatic hormone-sensitive prostate cancer. The present study aimed to identify prognostic factors in men with high- or low-metastatic burden treated with primary androgen-deprivation therapy. The study included 2450 men with de novo metastatic prostate cancer who were treated with primary androgen-deprivation therapy at 30 institutions across Japan between 2008 and 2017. We investigated the prognostic value of various clinicopathological parameters for progression-free survival (PFS) and overall survival (OS) in patients stratified by low- or high-metastatic burden. Among the 2450 men, 841 (34.3%) and 1609 (65.7%) were classified as having low- and high-metastatic burden, respectively. Median PFS of the low- and high-burden groups were 44.5 and 16.1 months, respectively, and the median OS was 103.2 and 62.7 months, respectively. Percentage of biopsy-positive core, biopsy Gleason grade group, T-stage, and N-stage were identified to be differentially prognostic. M1a was associated with worse PFS than was M1b in the low-burden group, whereas lung metastasis was associated with better PFS and OS than was M1b in the high-burden group. Differential prognostic factors were identified for patients with low- and high-burden metastatic prostate cancer. These results may assist in decision-making to select the optimal therapeutic strategies for patients with different metastatic burdens.

Complete biochemical response following metastasis-directed radiotherapy for oligometastatic prostate cancer: A case report.

Localized treatment has recently become an option for treating oligometastatic prostate cancer. Metastasis-directed therapy (MDT) is a new approach for localized treatment, and many clinical trials are ongoing. In the present case, biochemical recurrence occurred 8 months after a radical prostatectomy for localized prostate cancer, and oligometastases were diagnosed via whole-body magnetic resonance imaging. Metastasis-directed radiotherapy (MDRT) was performed on all oligometastatic sites. After MDRT without androgen deprivation therapy, the prostate-specific antigen (PSA) decreased to an undetectable level and did not increase for 24 months.

Prognostic Value of the LATITUDE and CHAARTED Risk Criteria for Predicting the Survival of Men with Bone Metastatic Hormone-Naïve Prostate Cancer Treated with Combined Androgen Blockade Therapy: Real-World Data from a Japanese Multi-Institutional Study.

BACKGROUND: The CHAARTED and LATITUDE trials demonstrated a prolonged overall survival (OS) for metastatic hormone-naïve prostate cancer (mHNPC) patients who receive up-front docetaxel or abiraterone acetate. These studies used their own risk criteria: CHAARTED trial defines high- and low-volume diseases and LATITUDE trial targeting a high-risk disease. The present study explored whether or not the CHAARTED and LATITUDE criteria were useful for predicting the outcome in Japanese bone mHNPC patients, including elderly patients (≥70 years). METHODS: A total of 532 mHNPC patients diagnosed from 2004 to 2014 in multithird referral cancer centers were enrolled in this study. All patients had bone metastasis and received combined androgen blockade treatment as an initial hormonal therapy. RESULTS: The number of patients with CHAARTED low-volume and high-volume diseases was 178 (33.5%) and 354 (66.5%), respectively. On the contrary, the number of patients with LATITUDE low-risk and high-risk diseases was 157 (29.5%) and 375 (70.5%), respectively. A total of 307 (57.7%) patients were defined as having both CHAARTED high-volume and LATITUDE high-risk disease. The median castration-resistant prostate cancer- (CRPC-) free survival was 12.5 months for the CHAARTED high volume, 56.9 months for the CHAARTED low volume, 13.6 months for the LATITUDE high risk, and 37.3 months for the LATITUDE low risk, respectively. The OS was 50.1 months in patients with CHAARTED high-volume disease, 95.1 months in patients with CHAARTED low-volume disease, 54.0 months in patients with LATITUDE high-risk disease, and 92.7 months in patients with LATITUDE low-risk disease, respectively. This trend was also observed in elderly (≥70 years old) patients. CONCLUSIONS: The patients with CHAARTED high-volume disease or LATITUDE high-risk disease showed a shorter CRPC-free survival and a shorter OS than those in the CHAARTED low-volume disease group or in the LATITUDE low-risk group among Asian Japanese bone metastatic HNPC patients.

Size of pelvic bone metastasis as a significant prognostic factor for metastatic prostate cancer patients.

INTRODUCTION: To investigate the potential prognostic value of image analysis of pelvic bone metastasis in newly diagnosed prostate cancer patients. METHODS: Data from 69 patients with both bone scintigraphy and pelvic CT images were selected for this analysis. Open source software (3D Slicer version 4.8.1.) was used for image analysis. Metastatic pelvic bone lesions were manually contoured, and radiomic features were extracted. As risk factors for overall survival (OS) and cause-specific survival (CSS), 105 radiomic features and clinical risk factors including age, initial prostate-specific antigen, Gleason score, TNM stage, lactate dehydrogenase (LDH), hemoglobin (Hb), alkaline phosphatase, extent of disease, visceral metastases, and radiotherapy were assessed by uni- and multivariate analyses. RESULTS: Median follow-up was 41 months (range 0-157 months). Five-year overall survival and cause-specific survival rate were 37.9% and 43.5%, respectively. After multivariate analysis, LDH, Hb, and "maximum 2D diameter" defined as maximum tumor size in the axial plane were detected as risk factors for OS. Gleason sum, LDH, and maximum 2D diameter were detected as risk factors for CSS. CONCLUSION: Maximum 2D diameter was detected as a significant prognostic factor for metastatic prostate cancer patients.

Potential effectiveness of local radiotherapy for extending survival and reducing symptomatic local events in patients with de novo metastatic prostate cancer.

Objectives: To evaluate the association between the use of local radiotherapy (RT) with the survival of patients with de novo metastatic prostate cancer and symptomatic local events (SLEs). Patients and methods: Patients were initially diagnosed with metastatic prostate cancer between 2008 and 2017 at 30 institutes in Japan. Prostate-specific antigen (PSA) progression-free survival (PSA-PFS) under initial androgen deprivation therapy and overall survival (OS) was compared between patients receiving local RT (RT group) and no RT (no-RT group) by multivariate Cox proportional hazard analyses. The occurrence rate of grade ≥2 SLEs was compared by multivariate logistic regression analyses. Propensity score matching (PSM) analyses were performed to compare PSA-PFS and OS of the groups in the high and low metastatic burden cohort. Results: Two hundred and five (7%) of 2829 patients received RT before PSA progression. Median PSA-PFS and OS were significantly longer in the RT group than in the no-RT group and the difference was significant in multivariate analyses (HR = 0.44, 95% CI = 0.33-0.57 and HR = 0.40, 95% CI = 0.27-0.60, respectively). The occurrence rate of grade ≥2 SLEs was significantly lower in the RT group (2%) than the no-RT group (9%) and the difference was significant in multivariate analyses (HR = 0.28, 95% CI = 0.10-0.76). Using PSM analyses, PSA-PFS and OS remained significantly different (HR = 0.64, 95% CI = 0.46-0.89 and HR = 0.47, 95% CI = 0.30-0.72, respectively), between the RT (n = 182) and the no-RT (n = 182) groups. The difference in OS was significant in the high metastatic burden cohort (HR = 0.55, 95% CI = 0.37-0.81). Conclusions: Addition of local RT to standard treatment for de novo metastatic prostate cancer patients tends to have the potential to extend survival, even in patients with high metastatic burden, and to reduce SLEs.

Pembrolizumab for Treatment-Refractory Metastatic Castration-Resistant Prostate Cancer: Multicohort, Open-Label Phase II KEYNOTE-199 Study.

PURPOSE: Pembrolizumab has previously shown antitumor activity against programmed death ligand 1 (PD-L1)-positive metastatic castration-resistant prostate cancer (mCRPC). Here, we assessed the antitumor activity and safety of pembrolizumab in three parallel cohorts of a larger mCRPC population. METHODS: The phase II KEYNOTE-199 study included three cohorts of patients with mCRPC treated with docetaxel and one or more targeted endocrine therapies. Cohorts 1 and 2 enrolled patients with RECIST-measurable PD-L1-positive and PD-L1-negative disease, respectively. Cohort 3 enrolled patients with bone-predominant disease, regardless of PD-L1 expression. All patients received pembrolizumab 200 mg every 3 weeks for up to 35 cycles. The primary end point was objective response rate per RECIST v1.1 assessed by central review in cohorts 1 and 2. Secondary end points included disease control rate, duration of response, overall survival (OS), and safety. RESULTS: Two hundred fifty-eight patients were enrolled: 133 in cohort 1, 66 in cohort 2, and 59 in cohort 3. Objective response rate was 5% (95% CI, 2% to 11%) in cohort 1 and 3% (95% CI, < 1% to 11%) in cohort 2. Median duration of response was not reached (range, 1.9 to ≥ 21.8 months) and 10.6 months (range, 4.4 to 16.8 months), respectively. Disease control rate was 10% in cohort 1, 9% in cohort 2, and 22% in cohort 3. Median OS was 9.5 months in cohort 1, 7.9 months in cohort 2, and 14.1 months in cohort 3. Treatment-related adverse events occurred in 60% of patients, were of grade 3 to 5 severity in 15%, and led to discontinuation of treatment in 5%. CONCLUSION: Pembrolizumab monotherapy shows antitumor activity with an acceptable safety profile in a subset of patients with RECIST-measurable and bone-predominant mCRPC previously treated with docetaxel and targeted endocrine therapy. Observed responses seem to be durable, and OS estimates are encouraging.

A phase I dose-escalation trial of stereotactic body radiotherapy using 4 fractions for patients with localized prostate cancer.

PURPOSE: To report results from our phase I dose-escalation study of stereotactic body radiotherapy (SBRT) using 4 fractions for patients with localized prostate cancer. MATERIALS & METHODS: Fraction sizes of 8 Gy, 8.5 Gy, and 9 Gy were defined as levels 1, 2, and 3. The prescribed dose was delivered to at least 95% of the planning target volume. Image-guided, intensity-modulated radiotherapy was delivered to all patients. Dose-limiting toxicity (DLT) was defined as acute toxicity of Grade 3 or higher. The maximum tolerated dose (MTD) was defined as the level at which ≥30% of patients showed DLT. The recommended dose (RD) was defined to be one dose level below the MTD. If no patients at level 3 showed DLT, level 3 was defined as the recommended dose (RD). RESULTS: Nine patients were enrolled in each level. All patients were low or intermediate risk. Median durations of follow-up for patients at levels 1-3 were 48.9 months, 42.6 months, and 18.4 months, respectively. Protocol treatment was completed for all patients. No patient showed DLT at each dose level. Level 3 was therefore designated as the RD for the phase II study. Although most toxicities were Grade 1, genitourinary toxicity was common compared to gastrointestinal toxicity. Three-year biochemical control rate was 90.3%. CONCLUSION: The dose level of 36 Gy in 4 fractions with a 2-day break was tolerable and highly encouraging for SBRT of localized prostate cancer. The phase II trial to confirm the efficacy and toxicity of this treatment is now on going. TRIAL REGISTRATION: UMIN, UMIN000010236 . Registered 13 March 2013.