High-grade non-muscle-invasive bladder cancer (HG-NMIBC) represents the most aggressive spectrum of this non-invasive cancer. This collective term includes all high-grade NMI urothelial carcinoma (UC), such as those without invasion (pTa), those with lamina propria invasion (pT1), and those that are only/have concomitant carcinoma in situ (CIS; pTis). These cancers have a high risk for intravesical recurrence (around 46–78% at five years) and progression (between 6–45% at five years) to muscle-invasive bladder cancer (MIBC). As with all UC, their presentation can be with visible haematuria or irritative lower urinary tract symptoms. The latter are common in patients with CIS. CIS may be detected in isolation (so-called primary CIS) or with a coexisting UC elsewhere (termed concomitant CIS). While urinary cytology has a moderate sensitivity and high specificity (>90%) for the detection of HG-NMIBC, cystoscopy is the most important diagnostic tool.
Prognostic significance of bladder neck involvement in non‐muscle‐invasive bladder cancer: A SEER database analysis with 19,919 patients
