Why accurate CIS diagnosis matters in bladder cancer care

In this video, urologists Arpeet Shah, MD, and Prithvi Murthy, MD, and pathologist Kenneth Beck, MD, discuss why recognizing carcinoma in situ (CIS) is critical to guiding appropriate treatment, expanding therapeutic options, and preventing disease progression.

Although CIS is a non–muscle-invasive lesion, Murthy emphasized that its biologic behavior more closely resembles high-grade T1 disease than low-grade Ta tumors, with a substantially greater risk of progression if left untreated. Unlike low-grade papillary lesions, which frequently recur but rarely progress, untreated CIS may lead to invasive or even metastatic disease. Because CIS can be multifocal and difficult to identify or completely resect, prompt recognition is essential so patients can receive appropriate intravesical therapy.

Murthy also noted that accurately identifying CIS can directly influence treatment selection beyond standard care. The presence of CIS may determine eligibility for specific clinical trial cohorts or FDA-approved therapies that carry a CIS indication, such as such as nadofaragene firadenovec-vncg (Adstiladrin), nogapendekin alfa inbakicept (Anktiva), and gemcitabine intravesical system (Inlexzo). As a result, confirming the diagnosis not only provides important prognostic information but may also broaden patients' access to novel intravesical therapies and other emerging treatment options.

In closing, the panel stressed that successful CIS diagnosis depends on close collaboration among urologists, pathologists, and patients. Beck encouraged clinicians to communicate proactively with pathology colleagues when CIS is suspected, while Murthy highlighted the importance of setting patient expectations that repeated evaluations may be necessary to locate occult disease. Shah concluded with a practical reminder for community urologists: a normal-appearing bladder should not rule out CIS when other clinical findings, such as positive cytology or persistent suspicion, suggest otherwise. Continuing the diagnostic workup until CIS is confidently excluded can meaningfully alter a patient's long-term management and outcomes.