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KEY CONCEPTS
Pembrolizumab has recently been approved for patients with Bacillus Calmette-Guerin (BCG)-unresponsive non–muscle-invasive urothelial cancer based on responses observed in a cohort of patients with carcinoma in situ in their bladders.
Neoadjuvant cisplatin-based chemotherapy remains the standard of care treatment for muscle-invasive bladder cancer. Dose-dense MVAC (methotrexate, vinblastine, doxorubicin, and cisplatin) has largely supplanted traditional MVAC because of its improved toxicity profile and shorter time to surgery.
Immune checkpoint inhibitors have been approved frontline treatment for patients with metastatic urothelial cancer who are not eligible for cisplatin-based chemotherapy. Programmed cell death ligand 1 (PD-L1) expression is required in this setting.
Immune checkpoint inhibitors are also approved after chemotherapy with level 1 evidence showing a survival benefit with pembrolizumab in the second-line setting and with avelumab in the maintenance setting in patients with stable disease or better for frontline chemotherapy. At the moment, there is no definitive evidence as to whether maintenance checkpoint inhibition or checkpoint inhibition at progression is the optimal treatment strategy. PD-L1 expression is not needed in the postchemotherapy setting.
In April 2019, the Food and Drug Administration (FDA) granted accelerated approval to erdafitinib, the first-in-class fibroblast growth factor receptor 3 (FGFR3) inhibitor based on efficacy in the second-line setting. FGFR3 mutations or fusions are required for treatment.
In December 2019, the FDA granted accelerated approval to enfortumab vedotin, the first antibody–drug conjugate approved for urothelial cancer based on efficacy in the third-line setting (postchemotherapy, postimmunotherapy). This antibody targets nectin-4, which is highly expressed in urothelial cancer, so expression levels are not necessary.
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The recent approvals of checkpoint inhibitors, the first biomarker targeted therapy for fibroblast growth factor receptor 3 (FGFR3) mutations, and the first antibody–drug conjugate have reinvigorated the field of urothelial cancer. Clinical trial programs in this field are rapidly evolving, with combinations of checkpoint inhibitors with these and other novel agents showing clinical activity that appears on par with what was initially achieved with MVAC (methotrexate, vinblastine, doxorubicin, and cisplatin) in the 1980s. Urothelial cancer is no longer just one disease. Additional developments in genomic medicine highlight the complexity and heterogeneity of urothelial cancer, providing the biologic framework for developing innovative precision therapy.
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The urinary tract conveys urine from the confluence of urinary tubules in the renal papillae to the outside world. A specialized epithelial surface known as the urothelium lines this entire path and is composed primarily of transitional cells, extending from the renal pelvis through the ureters, bladder, and urethra. In males, it also lines the terminal prostatic ducts and prostatic urethra. Although tumors arising from the urothelium can involve any organ along this path, about 90% of these cancers arise in the urinary bladder.
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Urothelial cancer is the fifth most common cancer diagnosis in the United States and is associated with cigarette smoking. In 2020, we anticipated about 85,000 new cases, ...