Introduction

We investigated the impacts of pathologically identified necrotic and sarcomatoid components on oncological outcomes in patients non-metastatic renal cell carcinoma (RCC).

Methods

After excluding patients with metastatic and/or lymph node invasive RCC, 1161 patients with the pathologic reports regarding the necrotic and/or sarcomatoid components were finally included for the analysis. Initially, the components of sarcomatoid and necrotic were tri-chotomized (0%, ?20%, >20%), respectively, and the impacts of each components were assessed using multivariate analysis. Mean follow-up duration was 65 months.

Results

Mean tumor size was 4.2 cm and pathologic stage was as follows; T1a in 702 (60.5%), T1b in 228 (19.6%), T2 in 81 (7.0%) and T3a in 124 (10.7%) and T3b or greater in 26 patients (2.2%). Sarcomatoid and necrotic component were pathologically identified in 37 (3.2%) and 184 patients (15.8%), respectively. In Kaplan-Meier analysis, 5-year recurrence-free survival was 92.3% in patients without sarcomatoid component and 48.9% in patients with sarcomatoid component (p<0.001). In addition, 5-year recurrence-free survival was 95.8% and 64.6% in patients with necrosis and without necrosis, respectively (p<0.001). In multivariate analysis, age at surgery (HR; 1.029, p=0.002), tumor size (HR; 1.175, p<0.001), locally advanced RCC (HR; 5.220, p<0.001), presence of necrosis (HR; 2.891, p<0.001) and % sarcomatoid component > 20% (HR; 2.963, p=0.002) were significant factor for predicting recurrence after surgery.

Conclusions

RCC patients with sarcomatoid component >20% and/or any necrotic component on pathologic examination should be carefully followed-up after surgery because of increased risk for the recurrence.

Funding

None