Yasuyuki Kobayashi

Alternative anti-androgen therapy has been widely used as a first-line treatment for castration-resistant prostate cancer, and it may affect treatment outcome of subsequent agents targeting the androgen receptor axis. We conducted the prospective observational DELC (Determination of Enzalutamide Long-term safety and efficacy for Castration-resistant prostate cancer patients after combined anti-androgen blockade followed by alternative anti-androgen therapy) study to evaluate the efficacy of enzalutamide in patients with castration-resistant prostate cancer who underwent prior combined androgen blockade with bicalutamide and then alternative anti-androgen therapy with flutamide. The DELC study enrolled 163 Japanese patients with castration-resistant prostate cancer who underwent alternative anti-androgen therapy with flutamide following failure of initial combined androgen blockade with bicalutamide in multiple institutions between January 2016 and March 2019. Primary endpoint was overall survival. Administration of enzalutamide was started at 160 mg orally once daily in all patients. The rate of decline of prostate-specific antigen by 50% or more was 72.2%, and median overall survival was 42.05 months. Multivariate analysis revealed that higher pretreatment serum levels of prostate-specific antigen (≥11.3 ng/mL; P = 0.004), neuron-specific enolase (P = 0.014) and interleukin-6 (≥2.15 pg/mL; P = 0.004) were independent risk factors for overall survival. Fatigue (30.0%), constipation (19.6%) and appetite loss (17.8%) were the most common clinically relevant adverse events. The enzalutamide dose was not reduced in any patient under the age of 70, but adherence was decreased in those over 70. In the DELC study, the safety of enzalutamide was comparable to that in previous reports. Serum levels of neuron-specific enolase and interleukin-6 were suggested as prognostic factors for castration-resistant prostate cancer with potential clinical utility.

Fat‐poor leiomyomatous angiomyolipoma, which is similar to smooth muscle tumors, is positive for smooth muscle markers and melanocytic marker human melanin black 45 (HMB‐45). We report a case of fat‐poor leiomyomatous angiomyolipoma arising from renal parenchyma negative for HMB‐45 diagnosed by combined staining with melanocytic markers HMB‐45 and Melan‐A.

Transurethral enucleation with bipolar (TUEB) is a safe and effective surgery for benign prostatic obstruction (BPO). However, few data exist concerning the influence of TUEB on erectile function (EF) in patients with BPO. To evaluate the influence of TUEB on EF in patients with BPO at 3- and 12-month follow-up. We prospectively enrolled 51 patients who underwent TUEB from June 2016 to April 2020. We evaluated maximum urinary flow rate (Qmax), postvoid residual urine (PVR), International Prostate Symptom Score (IPSS), quality of life (QoL), and International Index of Erectile Function-5 (IIEF-5) preoperatively and at 3- and 12-month follow-up. We classified the patients according to their preoperative IIEF-5 score into group 1 (IIEF-5 ≥10; n = 24) and group 2 (IIEF-5 <10; n = 27), and for further evaluation of EF, into subgroups a: severe (IIEF-5 5–7), b: moderate (8–11), c: mild to moderate (12–16), d: mild (17–21), and e: no erectile dysfunction (22–25). Data are displayed as median or median (interquartile range). The study comprised 51 patients with a median age of 75 (70.5–79.5) years. Median prostate and transition zone volumes were 69.5 (46.5–78.8) mL and 30.5 (19–43) mL, respectively. Urinary function improved significantly when comparing respective preoperative, 3-month, and 12-month follow-up values: Qmax (7.6, 12.9, 15.2 mL/s), PVR (50, 0, 0 mL), IPSS (20.5, 9, 6), and QoL (5, 2, 2), respectively. There was no significant change in IIEF-5 score across the three time points: 9, 7, 8. The IIEF-5 score slightly but significantly increased between the preoperative and 12-month follow-up values in group 2 (5, 5, 6) and subgroup a (5, 5, 5). TUEB was effective and safe surgery for patients with BPO and showed no significant influence on EF at 12-month follow-up after TUEB in patients with BPO.

Background: Malignant ureteral obstruction caused by extrinsic compression of a primary malignant tumour or by metastatic disease is an indicator of poor prognosis with a median life expectancy of about one year. We examined clinical outcomes following Resonance Metallic Ureteral Stent (Cook Medical, Bloomington, IN) placement in patients with malignant ureteral obstruction. Methods: This was a prospective study of patients with malignant ureteral obstruction who underwent Resonance Metallic Ureteral Stent placement from April 2016 to March 2021. We registered 21 patients (27 collecting systems) with malignant ureteral obstruction and observed them prospectively. The patients first underwent polymer ureteral stent placement followed by replacement with a metallic ureteral stent one month later. Primary outcome was the metallic ureteral stent patency period based on both serum creatinine and the level of hydronephrosis; secondary outcomes were factors affecting patency period and stent-related complications such as symptoms of obstruction (flank pain), bladder irritation, haematuria, and urinary tract infection (presence or absence of fever). Results: The study comprised 21 patients (six men, 15 women) with a mean age of 72 years. The median stent patency period in days was not available (NA) (95% CI 210–NA) due to the inability to extract this value from the Kaplan–Meier curve because the event rate did not reach 50%, and the one-year patency rate was 59.2% (95% CI 23.2–82.9). A normal serum creatinine (0.65 to 1.07 mg/dL for men and 0.46 to 0.79 mg/dL for women) one week after polymer ureteral stent placement was a significant factor affecting the long-term metallic ureteral stent patency period. There were no major complications. Conclusion: The Resonance Metallic Ureteral Stent was effective and safe for patients with malignant ureteral obstruction. A normal serum creatinine level one week after placement of a polymer ureteral stent may predict a longer patency period of metallic ureteral stents in patients with malignant ureteral obstruction.

Mesothelioma is an aggressive tumor originating from mesothelial cells. Mesothelioma of the spermatic cord is a very rare disease, and the most common presentation of this disease is that of aggressive mesothelioma with no description of mesothelioma in situ. We report an extremely rare case of mesothelioma in situ of the spermatic cord arising from a patent processus vaginalis. To our best knowledge, this is the first report of this finding. The identification of a patent processus vaginalis and investigation of single-layered atypical mesothelial cells led to the final diagnosis.

Combined immune checkpoint blockade with nivolumab and ipilimumab is standard therapy for the treatment of patients with previously untreated advanced renal cell carcinoma who are at intermediate or poor risk. However, data about the safety and efficacy of combined immune checkpoint blockade with nivolumab and ipilimumab in patients on hemodialysis are limited. Renal function has no known clinically important effects on the pharmacokinetics and clearance of nivolumab and ipilimumab. Further, most immune-related adverse events in patients on hemodialysis are thought to be manageable with the same treatments applied in patients with normal renal function. We present a case of advanced clear-cell renal cell carcinoma in a patient on hemodialysis who received combined immune checkpoint blockade with nivolumab and ipilimumab and who showed no evident signs of immune-related adverse events. Here, we confirm the safety and efficacy of combined immune checkpoint blockade with nivolumab and ipilimumab in a patient on hemodialysis.

Metastatic renal cancers are relatively common. Most are metastases to the renal parenchyma via a hematogenous route and are derived from lung, breast, and gastrointestinal cancer, malignant melanoma, and hematologic malignant cancer. However, little is known about renal capsule metastasis from other cancers. We report a 71-year-old woman with breast cancer who was treated with endocrine therapy. She presented with gross hematuria and was diagnosed as having right renal pelvic cancer and renal cell cancer. She underwent right laparoscopic radical nephroureterectomy. Pathological findings revealed right pelvic cancer and renal capsule metastasis. Renal capsule metastasis derived from renal pelvic cancer is very rare. When diagnosing renal capsule cancer, we believe that renal capsule metastasis should also be taken into consideration. Clinical and radiological differential diagnosis of renal capsule metastasis from renal cell cancer and primary renal capsule cancer is difficult. Assessment of the histopathological findings of the surgical specimens seems to be the only realistic approach to achieving the correct diagnosis.