Capturing recurrence in urothelial carcinoma: “more than meets the eye”

Urothelial carcinoma is the sixth most common cancer in the United States and is a significant source of mortality worldwide (1). Bladder urothelial carcinoma is a molecularly heterogeneous malignancy that typically presents as an exophytic tumour (or flat carcinoma in situ) confined to the mucosa or lamina propria (NMIBC); however, up to a third of patients have muscle-invasive (MIBC) and about 4% metastatic disease (mUC) at the time of diagnosis (2). While platinum-based chemotherapy has been the cornerstone of therapy for a long time, significant progress has been made recently in the treatment armamentarium of mUC, particularly with immune checkpoint and fibroblast growth factor receptor (FGFR) inhibition (3). For MIBC, neoadjuvant cisplatin-based chemotherapy has been shown to improve overall survival and thus is considered the standard of care prior to definitive locoregional therapy (4). Given the morbidity and mortality associated with mUC, optimizing early detection of recurrence after definitive therapy remains a very important, unmet need.