Concordance between clinical and pathologic staging of larger (cT2a-b) and more invasive (cT3a) renal cell carcinoma

Abstract

Introduction and Objectives

Among patients with renal cell carcinoma (RCC), 5%–23% of those with cT1 and smaller cT2 tumors may be upstaged to pT3a disease after surgery. The pathologic restaging rate of larger or clinically more invasive tumors is understudied and has implications for perioperative systemic therapy clinical trial enrollment. We examined rates of pathologic restaging for cT2a-b and cT3a RCC after surgery.

Methods

Using the National Cancer Database, we identified adult patients with cT2a, cT2b, and cT3a RCC undergoing partial or radical nephrectomy. We compared pathologic restaging rates between the clinical stage groups using a Chi-square test. Subgroup analysis of restaging rates was performed for histology (clear cell vs. non–clear cell), clinical nodal status (cN1 vs. cN0), and clinical metastatic status (cM1 vs. cM0). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the overall cohort and subgroups. Multivariable logistic regression was performed to assess predictors of pT3a upstaging among patients with cT2a and cT2b tumors.

Results

We identified 31,912 patients who met inclusion criteria (13,840 cT2a, 8,079 cT2b, and 9,993 cT3a). The overall rate of pathologic restaging was 47.4% for cT2a disease, 52.5% for cT2b disease and 9.5% for cT3a disease (P < 0.001; Fig. 1). Most of the restaging was upstaging for cT2a (36.7%) and cT2b (41.9%) disease. The positive predictive value was 52.5%, 47.5%, and 90.6% for cT2a, cT2b, and cT3a disease, respectively. On multivariable analysis, in patients with cT2 tumors, the presence of clinically node-positive (OR 2.8 [95% CI 2.43–3.17]) or metastatic disease (OR 2.4 [95% CI 2.18–2.65]), as well as higher nuclear grade (OR 6.7 [95% CI 5.1–8.9]) was associated with increased risk of pathologic upstaging (P < 0.001).

Conclusions

Restaging is common for patients with cT2a and cT2b tumors, but the specificity of cT3a staging is high, which suggests that the clinical/imaging characteristics concerning for locally invasive disease are generally accurate.