Introduction:

The role of lymphadenectomy in localized renal cell carcinoma (RCC) remains controversial. We sought to develop a preoperative nomogram called NODESAFE (NODE SAFEty) to predict nodal tropism (NT) defined as nodes invasion at the histological report (NI) or nodes metastasis (NM) at follow up.

Methods:

We conducted a retrospective analysis of the INMARC database of RCC patients who underwent primary surgical resection. Patients with clinical metastasis at presentation were excluded. NM was defined as development of a new adenopathy greater than 10mm at the CT scan during follow-up. NODESAFE model was constructed through a stepwise multivariable logistic regression (MLR) model. Accuracy was tested with receiver operator characteristic estimated area under the curve (AUC). Internal validation was performed through cross validation analysis. 

Results:

2,297 patients met inclusion criteria. On MLR: cN (OR 5.90, p<0.001), tumor size≥6cm (OR 3.04, p<0.001), c-reactive protein≥8.5mg/L (OR 1.98, p=0.011), neutrophile-lymphocyte ratio≥2.5 (OR 1.74, p=0.034) , low enhancement in CT imaging (OR 2.05, p=0.009), hypertension (OR 2.78, p<0.001) and Charlson Comorbidity Index≥6 (OR 2.57, p=0.001) were independent predictors for NT. NODESAFE model was constructed from these variables (Figure 1). AUC was 0.87 (Figure 2) and 0.84 after cross validation analysis. NODESAFE risk calculator is available at http://nodesafe.pythonanywhere.com/. 3.9% threshold probabilities displayed 73.5% sensitivity, 84.5% specificity and 98.8% negative predictive value.

Conclusion:

Combining clinical features, serum biomarkers and radiographic findings, we developed a model capable of predicting with accuracy nodes tropism. NODESAFE may refine clinical decision making with respect to the performance of lymphadenectomy at the time of surgery, post-surgical surveillance, and spur consideration for adjuvant therapy.

Funding: N/A