Citations

Abstract Enfortumab vedotin (EV), pembrolizumab, and EV plus pembrolizumab (EV/P) have rapidly reshaped the treatment landscape of advanced urothelial carcinoma, but toxicity increasingly determines treatment delivery, treatment continuity, and real-world benefit. As EV/P moves into broader clinical use, clinicians must distinguish adverse events related to antibody-drug conjugate exposure from immune-mediated toxicities and recognize syndromes in which both mechanisms may contribute. In this practical, mechanism-informed review, we synthesize pivotal trials, mature follow-up reports, and representative real-world cohorts describing the safety of EV monotherapy, pembrolizumab monotherapy, and EV/P in urothelial carcinoma. Because adverse-event reporting and ascertainment are heterogeneous across studies, including differences in preferred terms, composite categories, grading frameworks, and treatment-related versus all-cause reporting, we emphasize clinically interpretable patterns rather than pooled estimates. EV monotherapy is characterized by cutaneous toxicity, peripheral neuropathy, hyperglycemia, dysgeusia, and ocular events, including early epithelial/metabolic events and cumulative neuropathy. Pembrolizumab monotherapy has a lower overall high-grade toxicity burden but is defined by immune-mediated endocrinopathies, pneumonitis, hepatitis, colitis, and nephritis. Combination therapy produces a predictable overlap of these toxicity domains, creating diagnostic and management challenges for syndromes such as skin toxicity, diarrhea, fatigue, and pulmonary symptoms. We provide comparative visual toxicity signatures, regimen-specific summary tables, temporal toxicity mapping, and a pragmatic attribution framework that classifies events as EV-predominant, immune-predominant, overlap/indeterminate, or high-risk requiring initial interruption of both agents. This review aims to support bedside recognition, provisional attribution, early management, and safer implementation of EV/P in contemporary urothelial carcinoma practice.

Aim: Despite advances with immune checkpoint inhibitor (ICI)-based regimens in the past decade, patients with metastatic urothelial cancer (mUC) face a poor prognosis with few approved options. Platinum-based chemotherapy with paclitaxel and carboplatin (TC) +/– ICI may be a feasible choice. Methods: We generated an IRB-approved, HIPAA-compliant retrospective database of patients at Mayo Clinic Cancer Center with mUC who started TC +/– ICI after disease progression on ICI from January 2018 through December 2024. Baseline demographics, clinicopathologic features, and treatment outcomes were extracted from the electronic health record. Kaplan-Meier method was used to calculate median duration of response (DOR), progression-free survival (PFS) and overall survival (OS). Results: There were 32 patients who fit inclusion criteria, including 31 patients who had disease progression on ICI in the metastatic setting and 1 patient who developed metastatic disease on adjuvant nivolumab. Patients received a median of 4 cycles (range 1–14) of TC over median 12 weeks (range 3–53). Overall, 81% of patients received TC concurrently with an ICI, and 28% continued maintenance ICI after TC discontinuation (at the treating oncologist’s discretion due to adequate response or toxicity). The best objective response rate was 41% and disease control rate was 75%, with median DOR of 4.8 months (IQR 2.7–10.4), median PFS of 4.6 months (IQR 3.3–10.2), and median OS of 9.4 months (IQR 6.3–15.9). Some patients in this series had very durable responses with PFS > 12 months and OS > 24 months. TC +/– ICI was overall well tolerated with expected type and severity of adverse events. Conclusions: Strategies to overcome ICI resistance are needed, and TC +/– ICI after disease progression on an ICI shows promising tolerability and efficacy in this setting for patients with mUC. Our series was notable for some patients having a durable response. Validation in larger cohorts is warranted.

Abstract Background Extramammary Paget disease (EMPD) is a rare cutaneous adenocarcinoma. While localized disease has an excellent prognosis, metastatic EMPD is aggressive with no standardized systemic therapy. This study characterizes the clinicopathologic and molecular landscape of metastatic/recurrent EMPD to identify therapeutic vulnerabilities. Patients and methods We conducted a retrospective cohort study of 26 patients with metastatic or distantly recurrent EMPD treated at Mayo Clinic (2000-2025). Descriptive statistics were used to summarize baseline characteristics. Survival outcomes were estimated using Kaplan–Meier methods, with group comparisons performed using log-rank testing. Continuous variables were compared using nonparametric tests, and categorical variables were analyzed using appropriate comparative tests. Pathway-level genomic correlations with TCGA reference cohorts were assessed using Spearman rank correlation. Treatment responses were retrospectively evaluated from radiologic reports. Results The cohort was predominantly male (73.1%) and White (92.3%), with a median age of 68 (IQR, 53-79). Lymph nodes were the most common metastatic site (61.5%). The median overall survival (OS) was 20.0 months (95% CI, 0-40.4). IHC showed universal CK7 and GATA3 positivity, with 80% androgen receptor (AR) expression. HER2 was positive (3+) or amplified in approximately one-third of cases. NGS revealed frequent mutations in TP53 (68.8%), ERBB2 (50%), and CDKN2A/B (50%). A “triple-hit” deletion at the 9p21 locus (CDKN2A/B/MTAP) was identified in 25% of cases. Genomic profiling showed strong similarity to HER2+ breast and urothelial carcinomas. HER2-directed therapy was associated with longer overall survival (median OS 73.0 months [95% CI, 0-177.9] vs 19.0 months [95% CI, 0-41.4]; HR 0.50 [95% CI, 0.0-177.9], P = .3), although this difference did not reach statistical significance. Conclusion Metastatic EMPD exhibits distinct clinicopathologic and molecular features, including high AR and HER2 expression, TP53 and CDKN2A/B alterations, and similarity to systemic HER2+ malignancies. The observed activity of HER2-directed therapies in this cohort suggests the potential value of further investigating biomarker-guided treatment strategies in metastatic EMPD. NGS-guided profiling may inform precision treatment strategies, including AR-targeted therapy and emerging MTAP-directed approaches.

4515 Background: Adenocarcinomas of the urinary tract are rare malignancies with limited prospective data. Outcomes of triplet chemotherapy remain poorly defined. Methods: This was a prospective, single-arm, phase II study (NCT00082706) conducted at MD Anderson. Between 2005 and 2010, patients (pts) aged ≥18 years with ECOG 0–2 and metastatic or unresectable urachal (UA) or non-urachal adenocarcinoma (NUA) received frontline GemFLP (5-fluorouracil 200 mg/m² continuous infusion ×5 days with leucovorin 23 mg IV daily ×5; cisplatin 20 mg/m² IV daily ×5; gemcitabine 200 mg/m² IV on days 1 and 5). Best overall response (BOR) was assessed by imaging. Primary endpoints were objective response rate (ORR) and overall survival (OS); secondary endpoint was toxicity. PFS was calculated from treatment initiation and duration of response (DoR) from first CR/PR to progression or death; time-to-event endpoints were estimated by Kaplan–Meier (KM). Post hoc analyses evaluated baseline tumor markers (CEA, CA19-9, CA125, β-hCG) Treatment-related adverse events (TRAEs) were graded per CTCAE v5. Results: Forty-six pts were enrolled (28 UA, 18 NUA). Median age was 58 years; 41% were de novo metastatic, and 78% had visceral metastases. ORR was 44% (20/46). Among responders, median DoR was 8.6 months (95% CI 4.6–30.8). median PFS was 3.3 months (95% CI 2.3–8.4) and median OS (mOS) was 21.0 months (95% CI 15.9–35.3) There was no difference in PFS (p=0.39) or OS (p=0.99) between UA and NUA. Baseline CEA, CA19-9, CA125, and β-hCG were not associated with ORR or PFS. Higher baseline CA125 was associated with inferior OS (HR 1.33, 95% CI: 1.12–1.58; p =0.001) Subsequent systemic therapy was administered to 28 pts (60.9%); median number of subsequent treatment lines was 2 (range 1–5). The most common hematologic TRAEs were anemia (28.1%; grade ≥3 [G3] 12.5%), thrombocytopenia (21.9%; G3 12.5%), and neutropenia (12.5%; G3 9.4%). The most frequent non-hematologic TRAEs were dehydration (21.9%; G3: 6.2%), diarrhea (9.4%; G3 6.2%) and catheter-related thrombosis (9.4%; G3 9.4%). No grade 5 events occurred. Conclusions: In this prospective phase II study, frontline GemFLP achieved a 44% ORR with durable responses (mDoR 8.6 mo) and 21 mo mOS in advanced UA and NUA. Survival did not differ between UA and NUA subtypes. Baseline CA125 was associated with OS. Toxicity was manageable. These data provide a prospective benchmark for this rare disease. Clinical trial information: NCT00082706 . Variable UA (n=28) NUA (n=18) Characteristics Age, median [ICR] 58 [54– 62] 58 [54– 62] 67 [ 62-72] Race, n (%) White 22 (79) 11 61) Black 6 (21) 6 (33) Other 0 1 (6) Prior surgery for localized disease, n (%) 18 (64) 5 (28) Mets at baseline Any 24 (86) 7 (39) Lung 6 (21) 4 (22) Liver 3 (11) 0 Peritoneum 17 (61) 0 Bone 3 (11) 3 (17) Nodal-only mets 1 (3) 2 (10) Outcomes ORR (%) 43.5 35.7 55.6 BOR n (%) CR 4 (14) 2 (11) PR 6 (21) 8 (44) SD 11 (39) 4 (22) PD 6 (21) 3 (17) NE 1 (4) 1 (6)

TPS898 Background: Enfortumab vedotin with pembrolizumab (EV/Pembro) is now first-line therapy for locally advanced or metastatic urothelial carcinoma (la/mUC) following the EV-302/KEYNOTE-A39 trial, which demonstrated a 67.7% response rate and prolonged survival. However, ~35% of cancers exhibited primary resistance and most responders relapse within one year, with post-EV/Pembro therapies achieving < 15% response and median survival < 3 years. We previously showed that therapeutic plasma exchange (TPE) removed soluble PD-L1 and other immune checkpoint inhibitor (ICI) blocking soluble factors from the blood and that this overcame ICI resistance. Combining TPE with EV/Pembro rechallenge may overcome acquired resistance and restore antitumor immunity. Methods: RECIPE-B1 [NCT07087860] is an open-label, randomized phase II trial enrolling 50 patients (1:1) with EV/Pembro-refractory la/mUC and ECOG 0–2. Arm A receives TPE on days 1–3 followed by EV 1.25 mg/kg IV plus pembrolizumab 200 mg IV on day 3 of each 21-day cycle for the first three cycles, then continues EV/Pembro alone from cycle 4. Arm B receives investigator’s-choice next-line standard of care (SOC) per NCCN guidelines. Tumor assessments occur at the end of cycle 4 (±28 days) and every 12 weeks thereafter; safety is monitored each cycle (CTCAE v5.0). The primary endpoint is objective response rate (ORR) by RECIST 1.1, comparing TPE + EV/pembro versus SOC. Secondary endpoints include progression-free survival, overall survival, duration of response, quality of life (EORTC QLQ-CIPN20), and safety. Correlative studies evaluate circulating and urinary tumor DNA and exosomal biomarkers (including exosomal Nectin-4) as predictors of response and resistance. The trial is open at Mayo Clinic; as of September 2025, 2 of 50 patients have been enrolled, with planned accrual of ~2 patients/month and central coordination at Mayo Clinic and affiliates. Clinical trial information: NCT07087860 .

Non-muscle-invasive bladder cancer (NMIBC) comprises approximately 75% of new bladder cancer cases and generally carries a favorable prognosis, yet high rates of recurrence and progression necessitate close surveillance with frequent cystoscopies and repeated transurethral resections. Upfront treatment for high-risk disease is typically Bacillus Calmette-Guérin (BCG), although combinations with immune checkpoint inhibitors have reported results. Patients with BCG-unresponsive, intolerant, or refractory disease represent a subset of patients with high risk of progression, with early radical cystectomy being the standard approach for this setting. Global BCG shortages and the substantial impact of cystectomy on quality of life underscore the need for therapeutic alternatives. Over the past decade, investigational trials in immunotherapy have expanded treatment options for BCG-unresponsive NMIBC with CIS, leading to FDA approval of intravesical nadofaragene firadenovec, nogapendekin alfa-inbakicept, and systemic pembrolizumab. This narrative review summarizes developments in intravesical and systemic immunotherapies for NMIBC, highlights ongoing trials, and addresses controversies in trial design, treatment sequencing, comparative efficacy, and safety.

Abstract BACKGROUND Von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome characterized by development of multiple neoplasms, including central nervous system (CNS) hemangioblastomas, renal cell carcinoma (RCC), pancreatic neuroendocrine tumors (pNETs), and retinal hemangioblastomas. Belzutifan, a hypoxia-inducible factor 2-alpha (HIF-2α) inhibitor, has demonstrated efficacy in treating VHL-associated tumors. This study evaluates our institutional experience with belzutifan in patients with VHL-related tumors. MATERIAL AND METHODS We conducted a retrospective cohort study across three Mayo Clinic sites, including patients aged ≥18 years with genetically confirmed VHL disease who received belzutifan between October 2021 and March 2025. Clinical/radiological data, and adverse events (AEs) were extracted from electronic health records. Tumor responses were assessed using RECIST v1.1 criteria for RCC, pNET, CNS hemangioblastoma. Retinal hemangioblastoma responses were evaluated through ophthalmologic assessments. RESULTS Forty-five patients were included (median age 44 58% female). Sixty-seven percent had RCC, 91% had CNS hemangioblastomas, 53% had pNETs, and 62% had retinal hemangioblastomas. The median duration of belzutifan therapy was 22.6 months (range 1.0-41.4 months). Among patients with RCC (n=26), overall response rate (ORR) was 19% and median time to best response (MTBR) was 7.4 months. Five patients had partial response (PR), 15 had stable disease (SD), and 1 had progressive disease (PD). For CNS hemangioblastomas (n=41), ORR was 12%, MTBR was 6.2 months. 5 patients had PR, 30 had SD, and none had PD. For pNET (n=17), ORR was 41%, MTBR was 8.2 months. One patient had CR, 6 patients had PR, 6 had SD, none had PD. For retinal hemangioblastomas (n=28), 6 (21%) showed improvement, 9 (32%) remained stable, and 3 (11%) showed progression. MTBR was 6.7 months. Treatment-related AEs occurred in 98% of patients. Common AEs included anemia (89%), fatigue (80%), hypoxia (18%), and headache (13%). Grade 3 AEs were observed in 20% of patients, including anemia (7%), hypoxia (9%), fatigue (4%), pneumonitis (2%), loss of consciousness (2%). One patient experienced a grade 4 event (status epilepticus). Anemia management involved iron supplementation (n=11), RBC transfusion (n=3), dose reduction (n=2), treatment holiday (n=8), permanent discontinuation (n=1). Hypoxia management included dose reduction (n=1), treatment holiday (n=3), discontinuation (n=1). CONCLUSION Belzutifan shows clinical activity across various VHL-associated neoplasms in real-world practice, with a manageable safety profile. The lower ORR compared to the phase III trial may reflect differences in baseline disease, including lower tumor burden in our cohort. These findings support its continued use in VHL disease, with attention to monitoring and managing treatment-related AEs.

Abstract Objectives We aimed to assess the expression of biomarkers of response to antibody-drug conjugates (TROP2 and nectin-4) and immune microenvironment (NKG7, PD-L1, and B7-H3) in penile squamous cell carcinoma (pSCC). Methods Our archive was queried for patients who had a penectomy for pSCC between 2000 and 2022. Primary tumors were immunostained for B7-H3 and NKG7, while metastatic specimens were immunostained for TROP2 and nectin-4. Expression of PD-L1, TROP2, and nectin-4 in primary tumors was previously characterized. H-scores (0-300) were used to quantify expression. Associations between biomarkers, tumor-infiltrating lymphocytes (TILs), and clinicopathologic and outcome parameters were evaluated. Results For both TROP2 and nectin-4, H-scores within the lymph node metastases were higher compared to those within the primary tumors (mean, 264.5 vs 244.8, P = .0003; mean, 170.6 vs 146.7, P = .05, respectively; 33 paired specimens). For B7-H3 (n = 107), 32.7% of the primary tumors had an H-score of more than 0. In 34.8% of the cases, NKG7 expression was observed in 25% to 50% of the TILs. A significant association was noted between TIL density, B7-H3, NKG7, and PD-L1 expression. Conclusions Therapeutic strategies targeting TROP2 and nectin-4 hold promise for patients with advanced pSCC. The potential of PD-L1, B7-H3, and NKG7 for predicting response to immunomodulatory treatment warrants further research.