Kazuo Nishimura

Objective: We aimed to evaluate clinical outcomes after metastasis-directed radiotherapy (MDRT) in patients with oligoprogressive castration-resistant prostate cancer (CRPC) and to identify factors associated with durable disease control. Methods: We retrospectively analyzed 43 patients with oligoprogressive CRPC who underwent MDRT between 2020 and 2024 at a single institution. The primary endpoint was progression-free survival (PFS), defined using composite criteria from the Prostate Cancer Working Group 3 and Response Evaluation Criteria in Solid Tumors. Secondary endpoints included prostate-specific antigen (PSA) response and secondary PFS (PFS2) in patients who underwent repeat MDRT. Clinical factors associated with PFS were assessed by Cox proportional hazards regression. Results: The median PFS after initial MDRT was 9.0 months (95% confidence interval [CI], 7.0–11.0). A PSA decline of ≥50% was achieved in 53% of patients, including a ≥ 90% decline in 21%. Thirteen patients (30%) underwent repeat MDRT for recurrent oligoprogression, with a median PFS2 of 14.0 months (95% CI, 10.0–25.0). In multivariable analysis, prior androgen receptor signaling inhibitor (ARSI) exposure for CRPC (hazard ratio [HR], 4.53; 95% CI, 1.75–11.73) and PSA doubling time ≤ 2.4 months (HR, 3.24; 95% CI, 1.29–8.15) were independently associated with shorter PFS. No grade ≥ 3 treatment-related adverse events were observed. Conclusions: MDRT was followed by clinically meaningful disease control in patients with oligoprogressive CRPC. Prior ARSI exposure for CRPC and a shorter PSA doubling time were associated with earlier progression. These findings are exploratory and warrant validation in prospective studies.

As life expectancy increases, a growing number of older adults undergo radical prostatectomy for localized prostate cancer; however, longitudinal age-specific functional outcomes remain insufficiently characterized. We conducted a prospective multicenter cohort study evaluating age-stratified trajectories of patient-reported outcomes (PROs) assessed using the Expanded Prostate Cancer Index Composite (EPIC) and perioperative complications following robot-assisted radical prostatectomy (RARP). A total of 604 patients were categorized into three age groups (< 65, 65–74, and ≥ 75 years). PROs were assessed using the EPIC at baseline and at 1, 3, 6, and 12 months postoperatively, and longitudinal changes were analyzed using linear mixed-effects models. Urinary function declined transiently after surgery in all age groups and substantially recovered by 12 months, with no significant differences between men aged ≥ 75 years and younger patients. Sexual function decreased irrespective of age, although younger patients maintained higher absolute scores after nerve-sparing procedures. In contrast, sexual bother demonstrated an age-dependent pattern, with minimal change observed in men aged ≥ 75 years. Perioperative complication rates did not differ significantly across age groups. These findings suggest that chronological age alone should not preclude consideration of RARP in appropriately selected elderly patients and provide evidence supporting individualized surgical decision-making in an aging population.

Introduction: Reactive lymphoid hyperplasia (RLH) is a rare benign lymphoproliferative disorder that rarely involves the kidney and has not been reported in association with regional lymphadenopathy. Case Presentation: A 70‐year‐old woman was incidentally found to have a left renal mass. Contrast‐enhanced computed tomography revealed a 20‐mm enhancing renal lesion with enlarged hilar lymph nodes, leading to a preoperative diagnosis of renal cell carcinoma with nodal metastasis (cT1aN1M0). Open radical nephrectomy with regional lymphadenectomy was performed. Histopathological analyses established a diagnosis of reactive lymphoid hyperplasia. No additional treatment was administered, and the patient has remained free of recurrence for 3 months. Conclusion: We report the first case of RLH accompanied by regional lymph node enlargement. Because RLH can closely mimic renal cell carcinoma on imaging, it should be considered in the differential diagnosis of renal masses when the clinical presentation is inconsistent with typical renal cell carcinoma.

Objective: To evaluate adverse events in testicular cancer survivors using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire‐Testicular Cancer 26 (EORTC QLQ‐TC26). Methods: Testicular cancer survivors at eight high‐volume institutions in Japan were surveyed regarding age, International Germ Cell Consensus Classification, number of chemotherapy cycles, paclitaxel use, follow‐up period after treatment, and adverse events scores of EORTC QLQ‐TC26. Adverse events scores were assessed by the number of chemotherapy cycles and the follow‐up period. Results: A total of 551 testicular cancer survivors responded to the adverse events questionnaires of EORTC QLQ‐TC26. Median age at response was 43 years and median follow‐up was 61 months. Chemotherapy was administered to 393 (71%) survivors, and paclitaxel was used in 91 (17%) survivors. Testicular cancer survivors who received three or more cycles of chemotherapy showed significantly worse adverse events scores than those without chemotherapy. Scores for tingling or numbness in the fingers or toes, pale/cold fingers or toes, and problems with hearing were affected by chemotherapy. Tingling or numbness tended to improve over time, whereas problems with hearing showed no evidence of improvement. In addition, scores for tingling or numbness were worse when paclitaxel was used. Conclusions: Testicular cancer survivors suffered from adverse events with three or more cycles of chemotherapy, and problems with hearing did not improve after treatment. We should provide testicular cancer survivors with adequate information about long‐lasting adverse events, particularly problems with hearing.

Background Systemic therapy for metastatic renal cell cancer (mRCC) has changed significantly due to randomized controlled trial results. We investigated whether these changes affect real-world outcomes and clarified factors associated with treatment outcomes in patients from a single institution outside of clinical trials. Methods We retrospectively reviewed records of mRCC patients treated at Osaka International Cancer Institute between January 2005 and May 2024. Between-group analysis of progression-free survival (PFS) and overall survival (OS) by Kaplan–Meier comparison and identification of survival-associated factors by univariate and multivariate analyses were performed. Patients assumed ineligible for clinical trials were analyzed in subgroups according to any of Eastern Cooperative Oncology Group performance status > 1, hemoglobin level < 9.0 g/dL, estimated glomerular filtration rate < 40 mL/min/1.73 m², platelet count < 100,000/μL, neutrophil count < 1500/μL, non-clear cell histology, or brain metastasis. Results In total, 320 patients were evaluated: 2005–2009, n = 58; 2010–2014, n = 77; 2015‒2019, n = 86; and 2020‒2024, n = 99. Significant between-group differences were observed for median PFS (7 vs. 8 vs. 12 vs. 20 months; p = 0.0048) and (35 vs. 38 vs. 67 vs. 52 months; p = 0.0206). Multivariate analysis revealed that first-line or subsequent-line immune checkpoint inhibitor (ICI) use was an independent factor for OS (HR: 0.28, p < 0.0001). Even among 112 (35%) trial-ineligible patients, multivariate analysis demonstrated that the use of first-line or subsequent-line ICI was an independent factor for OS (HR: 0.26, p < 0.0001). Conclusion Over time, treatment outcomes appeared to have improved with real-world treatment for mRCC, with use of ICIs being related to improvements in treatment outcomes.

Objectives: This study aimed to evaluate predictors of late biochemical recurrence in patients with no recurrence at 5 years after radical prostatectomy (RP).Methods: We retrospectively investigated patients who underwent RP for prostate cancer in our institute from 1999 to 2016, selecting those with no biochemical recurrence at 5 years post‐RP. These patients did not receive neoadjuvant and adjuvant hormone therapy. Following RP, patients were regularly monitored using ultra‐sensitive prostate‐specific antigen (PSA) measurements, with a detection limit of 0.01 ng/mL. Biochemical recurrence was defined as PSA level ≥0.2 ng/mL, confirmed by subsequent PSA >0.2 ng/mL.Results: Among 581 patients who underwent RP, 312 with no biochemical recurrence at 5 years post‐RP were selected. The median follow‐up period was 123 months. The 10‐year biochemical recurrence‐free survival rate for this cohort was 89.6%. Patients with a PSA value p = 0.035; hazard ratio 37.5, 95% confidence interval 11.6–121.3, p < 0.001, respectively). Patients with Grade Group of 4 or more had a significantly reduced PSA doubling time at biochemical recurrence compared to those with Grade Group of 3 or less.Conclusions: Among patients whose PSA levels remain below 0.02 ng/mL at 5 years after RP, the risk of subsequent late biochemical recurrence is very low. Utilizing ultra‐sensitive PSA measurements at the 5‐year mark can provide useful information regarding the need for follow‐up beyond 5 years.

Aim: We aimed to determine Japanese metastatic castration resistant prostate cancer (CRPC) patients' Ra-223 treatment experience. Patients & methods: Patients answered the Cancer Therapy Satisfacti... Plain language summary What is this study about? We wanted to know the treatment experience with Radium-223 (Ra-223) among Japanese prostate cancer patients. Ra-223 is a radioactive molecule used f... Tweetable abstract A study on Japanese metastatic castration resistant prostate cancer patients who receive Radium-223 therapy showed that treatment satisfaction, anxiety and health-related quality...

The aim of this study was to evaluate the effectiveness of intensity-modulated radiation therapy in combination with long-term androgen deprivation therapy for high-risk and very high-risk localized prostate cancer while also investigating factors associated with the therapeutic effect. Men who fulfilled criteria for the National Comprehensive Cancer Network high-risk or very high-risk localized prostate cancer and were treated with definitive intensity-modulated radiation therapy (74–78 Gy) of the prostate and the seminal vesicle combined with androgen deprivation therapy in our institution from 2007 to 2016 were identified (n = 197). In principle, patients received androgen deprivation therapy for 3–6 months before radiation, concurrently, and for 2 years after completion of intensity-modulated radiation therapy. The median follow-up period was 96 months. The 5-year and 10-year overall survival rates in the overall population were 96.9% and 89.3%, respectively. The 5-year and 10-year cumulative incidence rates of biochemical failure were 2.5% and 16.3% in the high-risk group, and 8.6% and 32.0% in the very high-risk group, respectively, indicating a significant difference between the two groups (P = 0.023). Grade Group 5 and younger age (cutoff: 70 years old) were independent predictors of recurrence (P = 0.016 and 0.017, respectively). Patients exhibiting biochemical failure within P = 0.039) when contrasted with those who had a longer interval to biochemical failure. Patients with the National Comprehensive Cancer Network very high-risk prostate cancer, particularly those with Grade Group 5 and younger age, showed worse outcomes following intensity-modulated radiation therapy and long-term androgen deprivation therapy.

As immune checkpoint inhibitors become more widely available, the optimal management of immune-related adverse events (irAEs) is becoming increasingly important. Although irAEs are diverse, reports on cytokine release syndrome are rare. Here, we report a case of a 48-year-old man with relapsing cytokine release syndrome after receiving pembrolizumab and axitinib combination therapy for metastatic renal cell carcinoma. During dose reduction of prednisolone for immune-related hepatitis on day 33 after starting pembrolizumab plus axitinib, the patient suddenly developed abdominal pain, and a few hours later became hypotensive and poorly oxygenated. Despite the use of a ventilator and high doses of catecholamines, blood pressure and oxygenation could not be maintained. Extracorporeal membrane oxygenation and intra-aortic balloon pumping were also administered. The cytokine release syndrome (CRS) was treated with tocilizumab, and his general condition improved. Lower-grade CRS relapsed four times despite a moderate dose of oral prednisolone with mycophenolate mofetil or tacrolimus. After gradual reduction in prednisolone over 5 months, the patient was discharged from the hospital. Partial remission of renal cell carcinoma continued for 21 months, and salvage radical nephrectomy was performed. The patient remained disease-free without the need for further treatment 9 months after surgery.

Progression of bone metastases is the primary cause of death in prostate cancer, and skeletal-related events (SREs), including pathologic fractures, spinal cord compression, radiation, or surgery to bone can impair patients’ quality of life. Over the past decade, the development of cytotoxic agents, androgen-receptor-axis-targeted therapies (ARATs), and radioligand therapies has prolonged overall survival of prostate cancer patients with bone metastases and reduced the risk of SREs. The use of bone-modifying agents has also contributed to the reduced risk of SREs. Initial use of a cytotoxic agent, docetaxel, or an ARAT agent with androgen deprivation therapy (ADT) is the current approach to metastatic castration-sensitive prostate cancer. However, there is no consensus on the optimal medication for upfront use in combination with ADT, or on specific patient selection. Recently, next-generation imaging modalities, such as whole-body magnetic resonance imaging and prostate-specific membrane antigen-positron emission tomography have been utilized to detect bone metastases at an early stage. In addition, metastasis-directed therapy, such as stereotactic body radiation therapy, has been attempted. In the future, patients with bone metastatic prostate cancer will be divided into subgroups and their treatment options will be tailored to their specific characteristics.