The Impact of Lymphovascular Invasion on Risk of Upstaging and Lymph Node Metastasis at the Time of Radical Cystectomy

Background: Lymphovascular invasion (LVI) in muscle-invasive bladder cancer is associated with a poor prognosis when identified from radical cystectomy (RC) specimens. However, LVI is not clearly emphasized in any risk models to guide clinical decision-making. The impact of LVI on the risk of lymph node (LN) metastasis after a transurethral resection of bladder tumor (TURBT) specimen is less understood.

Objective: The goal was to describe the impact of LVI and the risk of LN metastasis at each clinical stage of urothelial carcinoma of the bladder (UC).

Design, setting, and participants: The National Cancer Database was queried for patients with bladder cancer who underwent RC with LN dissection from 2004 to 2014. Patients with non-bladder primary, non-UC histology, clinical metastatic disease, and having received chemotherapy/radiation were excluded. Pathologic LN positive rates at RC were determined.

Outcome measurements and statistical analysis: The primary outcome was pathologic upstaging at RC and pathologic node positivity. Secondary outcomes included determining overall survival (OS). All hypotheses testing were two-sided and a p value of <0.05 was considered statistically significant. All statistical analyses were performed using Stata version 13.1.

Results and limitations: A total of 3007 patients with UC underwent RC with pelvic LN dissection. In patients with LVI, the risk of LN metastasis was significantly higher at each clinical stage as was the rate of pathologic upstaging. Patients with LVI on TURBT had worse OS stage for stage in pure UC (p<0.001). Limitations include that there was no central pathologic review and the number of TURBTs per patient was not known.

Conclusions: Patients with UC with LVI had worse OS and are at higher risk for LN-positive disease and pathologic upstaging at surgery than patients without LVI.

Patient summary: In this report we examined the impact of lymphovascular invasion (LVI) at transurethral resection of bladder tumor on pathologic upstaging and lymph node metastasis at radical cystectomy using the National Cancer Database. We identified LVI as being prognostic at each stage of urothelial carcinoma.