Nozomi Hayakawa

Objective: This study aimed to evaluate the clinical relevance of early relative dose intensity (eRDI) during enfortumab vedotin (EV) monotherapy in patients with metastatic urothelial carcinoma (mUC) based on a Japanese real‐world multicenter cohort. Methods: We retrospectively analyzed 119 patients with mUC who received EV. The temporal trend of total relative dose intensity (tRDI), defined as the cumulative relative dose intensity during treatment, was assessed over the first 5 months. eRDI, calculated as the mean RDI over the initial 3 months, was also evaluated. Survival analyses were performed in 84 patients evaluable beyond the first radiographic assessment, excluding those with early progressive disease (PD). Patients were stratified by eRDI (≥ 80% vs. < 80%), and progression‐free survival (PFS) and overall survival (OS) were compared. Subgroup analyses were conducted according to the presence or absence of adverse event–related dose modification (AE‐related DM). Results: Dose intensity gradually declined during the early treatment phase. The eRDI was not significantly associated with PFS or OS in the PD‐excluded cohort ( n = 84). However, among patients without AE‐related DM ( n = 44), high eRDI was associated with significantly longer PFS (median 11.7 vs. 4.2 months; p = 0.001) and OS (not reached vs. 13.8 months; p = 0.021). No significant association was observed between eRDI and survival in patients with AE‐related DM. Conclusions: Although eRDI was not an overall significant prognostic factor, it showed clinical relevance in patients without AE‐related DM. These findings underscore the importance of preserving eRDI in patients with sufficient tolerability and support individualized dosing strategies for EV therapy.

Introduction: Secondary bladder tumor is rare. We report a case of a bladder tumor initially thought to be a recurrence of non‐muscle invasive bladder cancer that was ultimately identified as metastasis from gastric cancer treated 16 years prior.Case presentation: A 75‐year‐old male with a history of gastric, prostate, and recurrent non‐muscle invasive bladder cancer was diagnosed to have multiple bone metastases. Open bone biopsy and cancer gene panel testing identified the primary origin of the metastases as gastric cancer. Retrospective evaluation revealed that what was initially suspected as recurrent bladder tumors were actually metastases from the gastric cancer.Conclusion: In cases of metastases with an unknown primary origin, detailed evaluation, including biopsy of the metastatic lesion and genomic testing, is recommended.

A 72-year-old female was referred to our institution for further evaluation of right renal tumor detected during work-up for macroscopic hematuria in other hospital. CT urography performed at our institution suggested renal pelvic tumor. Voiding cytology was atypical. CT also revealed a small mass in the right mammary gland. Percutaneous needle biopsies were performed on the right mammary gland and renal mass, leading to a pathological diagnosis of UC with plasmacytoid subtype, suggesting metastasis from the renal pelvic UC to the mammary gland. She had a favorable response to four cycles of dose-dense MVAC therapy; therefore, we performed nephroureterectomy. One month after nephroureterectomy, new intraperitoneal metastatic lesions were observed and pembrolizumab therapy was started. After seven doses of pembrolizumab, CT revealed a marked size reduction of intraperitoneal metastases and the mammary metastasis remained small.

Introduction: Up to 10% of patients with renal cell carcinoma present with tumor thrombus in the inferior vena cava. We report that a case of small renal cell carcinoma with tumor thrombus extending above the diaphragm for which transvenous biopsy was performed for diagnosis.Case presentation: A 79‐year‐old man performed computed tomography to evaluate hepatic dysfunction, which revealed intravenous tumor extending above the diaphragm and a 15‐mm‐sized exophytic tumor in right kidney. Imaging suggested that the renal tumor was renal cell carcinoma. As this tumor was small and exophytic, confirmation of the intravenous tumor being tumor thrombus associated with renal cell carcinoma was difficult. We simultaneously performed transvenous biopsy on the intravenous tumor and percutaneous biopsy on the renal tumor for obtaining histologic diagnoses. The final diagnosis was small renal cell carcinoma accompanied by tumor thrombus above the diaphragm.Conclusion: Transvenous biopsy may be useful for the definitive diagnosis of inferior vena cava‐tumor thrombus in cases of small renal cell carcinoma.