Non-muscle invasive high grade urothelial carcinoma of the bladder. Which factors can influence understaging at the time of radical cystectomy?

Objective: To evaluate the main factors which influence understaging in patients with T1G3 non-muscle invasive bladder cancer (NMIBC). Materials and methods: 109 patients with T1/G3 underwent transurethral resection of bladder tumor (TURBT) and then radical cystectomy (RC) with pelvic lymph nodes dissection. A number of variables were considered when evaluating the detection of understaging. We considered the patients age and gender, as well as the size, number, location and morphology of their tumor. We also considered coexistence of bladder carcinoma in situ (CIS), microscopic vascular invasion and deep lamina propria invasion. The level of experience of the surgeon was also analyzed. Results: in RC samples muscle invasion, that is understaging, was detected in 74 (67.9%) patients, while 35 (32.1%) patients were appropriately staged. In these cohort of patients with high grade tumors, understaging was associated with deep lamina propria and microscopic vascular invasion, multiple tumors, tumor size > 6 cm, tumor location (trigone and dome), presence of residual tumor; age, gender, tumor morphology, CIS associated, and experience of urological surgeon were not associated with clinical understaging. Conclusions: in our study, evaluating patients with high grade NMIBC at first TURBT, we identified some risk factors that need to be considered and that are able to increase the risk of understaging: deep lamina propria and microscopic vascular invasion, multiple tumors, tumor size > 6 cm, tumor location (trigone and dome), presence of residual tumor. When these risk factors are present, performing an early cystectomy, and not a re-TURBT, could lower the risk of worse pathological finding due to rapid disease progression of the high grade tumors, and can prolong survival.