Impact of lymphovascular invasion on survival in surgically treated Upper Tract Urothelial Carcinoma: a nationwide analysis.

OBJECTIVES: To assess the prognostic ability of LVI in UTUC as a predictor of overall survival (OS) using a large North American cohort.

MATERIAL AND METHODS: Our cohort included 5,940 cM0 UTUC patients who underwent a radical nephroureterectomy (RNU), between 2010 and 2016, within the National Cancer Database (NCDB). The main variable of interest was LVI status, and its interaction with pathological nodal (pN) status. Kaplan-Meier curves were used to depict the OS also stratifying patients on LVI status. Cox regression analysis tested the impact of LVI status on OS after accounting for the available covariates.

RESULTS: Median (IQR) for age at diagnosis was 71 (63 - 78) and most patients had pT1 stage disease (48.6%). Nodal status was pN0, pN1 and pNx in 45.8%, 6.3% and 47.9%, respectively. Overall, 22.1% had LVI. The median (IQR) follow-up time was 32.6 (16. - 53.3) months. At 5-years postoperative follow-up, the estimated OS rate was 28% in patients with LVI vs. 66% in those without LVI (p<0.001). When patients were stratified based on nodal status those rates were 32% vs 68% in pN0 patients (p<0.001), 23% vs 30% in pN1 patients (p = 0.8), and 28% vs 65% in pNx patients (p<0.001). On multivariable analysis, the presence of LVI was associated with less favorable OS (HR 1.79, 95% CI: 1.60-1.99, p<0.001).

CONCLUSION: Our study assessed the impact of LVI on OS in UTUC patients in a large North-American nationwide cohort. Our series, as the largest to-date, indicate that LVI is associated with less favorable survival outcomes in UTUC patients after RNU, and this variable could be used in counselling patients about their prognosis and might be a useful tool for future trials to risk-stratify patients.