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Kidney Week

Abstract: PO2178

Comparative Analysis of Characteristics and Survival Outcomes of Clear Cell and Sarcomatoid Subtypes of Renal Cell Carcinoma: Results from the SEER Database 2000-2017

Session Information

  • Onco-Nephrology - 1
    October 22, 2020 | Location: On-Demand
    Abstract Time: 10:00 AM - 12:00 PM

Category: Onco-Nephrology

  • 1500 Onco-Nephrology


  • Attia, Doaa, Cleveland Clinic, Cleveland, Ohio, United States
  • Behera, Tapas Ranjan, Cleveland Clinic, Cleveland, Ohio, United States
  • Attia, Sara Aly, Northeastern University, Boston, Massachusetts, United States

Renal cell carcinoma (RCC) accounts for more than 90% of kidney cancers. Clear cell RCC (ccRCC) is the commonest type, while sarcomatoid RCC(sRCC) is rare and constitutes 5% of all RCCs. sRCC is known for aggressive clinical course and poor prognosis. In this study, we sought to compare the epidemiological features and survival trends of ccRCC with sRCC, using SEER dataset 2000-2017.


The Surveillance, Epidemiology and End Results (SEER) database was used to identify all adult patients (≥18 years) diagnosed with ccRCC and sRCC between 2000 and 2017.Variables included age, sex, ethnicity, laterality, staging, histological grade, and nephrectomy. Overall survival was estimated using the Kaplan-Meier method, and compared using the Log-Rank test. Multivariable covariate-adjust cox models were used for adjusted survival analyses.


A retrospective cohort study of 20248 patients (19398 ccRCC, 850 sRCC) with overall survival rate of 38% (40% ccRCC and 16.2%ssRCC). Although the two subtypes share similar demographic characteristics, including mean age (66.8±13.7 for ccRCC vs 62.9±12 for sRCC), male-female ratio (1.71:1 vs 2.3:1), and having caucasian race more affected (79% vs 82%), sRCC had a significantly worse prognosis in univariate analysis with median overall survival of 7 months vs 30 months for ccRCC. Caucausian male patients were more affected in both types. But neither sex nor race significantly affected survival in sRCC (P 0.814, 0.794 respectively), however, black americans have worse outcomes in ccRCC (HR 1.123[1.083-1.163], P < 0.001). On multivariate regression analysis, advanced stage, high histological grade, and older age 65+years (HR 1.002, 95%CI [1.001-1.00], P < 0.001) were associated with worse outcomes. Patients with cancer-related death had significantly shorter survival time in both RCCs (P<0.001). Nephrectomy was associated with better survival outcomes (HR 0.486 [0.459-0.514], P < 0.001).


sRCC had worse prognosis. Advanced stage, high histological grade, and older age are the most important predictors of survival in both subtypes of RCC. Although caucasian male patients were more affected in sRCC, gender and ethnicity have no impact on survival. Nephrectomy imparts better survival benefits in both subtypes.