Introduction:

The role of lymphadenectomy in upper tract urothelial carcinoma (UTUC) remains controversial. We sought to develop a preoperative nomogram to predict nodal tropism (NT) defined as nodes invasion at the histological report (NI) or presence of nodes metastasis (NM) at follow up. 

Methods:

We conducted a retrospective analysis of the ROBUUST database of UTUC patients who underwent robotic nephroureterectomy . NI was defined as presence of positive nodes at final histological report, while NM was defined as the emergence of newly detected retroperitoneal lymphadenopathy (>10 mm) during the follow-up period. Patients who underwent neoadjuvant or adjuvant chemotherapy were excluded from analysis. Primary objective was to develop a predictive model for NT. The model was developed through a stepwise multivariable logistic regression (MLR).  Secondary outcomes pertain to internal validation though cross validation analysis. Accuracy of the model was tested with receiver operator characteristic/area under the curve (AUC), and calibration plot. 

Results:

1,117 were analyzed [755(64.1%) male and 422(35.8%) female]. On MVR cN+[Odds ratio(OR) 8.19, p<0.001]  cT4 vs cTa (OR 10.38 , p=0.012)  history of bladder cancer (OR 6.66 , p<0.001) high-grade cytology (OR 2.90, p<0.001), platelets lymphocyte ratio≥130 (OR 1.77, p=0.021), diabetes mellitus (OR 1.90, p=0.023), and symptoms at diagnosis (OR 2.16, p=0.008) were independent predictors for NT. A nomogram was developed based on the MVL (Figure 1). AUC of the model was 0.83 (Figure 2). AUC after internal validation was 0.81 (95% confidence interval 0.76-0.87; Figure 2). A 7% threshold probability demonstrated 80.2% sensitivity, 75.4% specificity and 97.5% negative predictive value. 

Conclusion:

By integrating patient characteristics and serum biomarkers, we've engineered a predictive model for node tropism. This model has the potential to improve clinical choices, with respect to the performance of lymphadenectomy at the time of surgery, post-surgery monitoring, and may spur considerations for supplementary treatment. Further investigation is requisite. 

Funding: N/A