Sarcomatoid features and lymph node-positive disease in chromophobe renal cell carcinoma

The presence of sarcomatoid features and/or lymph node-positive disease may be associated with a worse prognosis in chromophobe renal cell carcinoma (ChRCC). We sought to better characterize patients' long-term outcomes with these features compared with those without these features.

We identified 300 patients treated for sporadic, unilateral, nonmetastatic ChRCC between 1993 and 2019. Clinical and pathologic features were summarized, and cancer-specific survival (CSS) and recurrence-free survival (RFS) were analyzed using Kaplan-Meier plots. Cox regression analysis was performed to determine factors associated with recurrence. Patients with sarcomatoid features and/or nodal disease were grouped as high-risk in a secondary analysis.

The median age was 60 years, 43.7% were female, 29.3% had pT3/T4 disease, 3.3% had sarcomatoid features, and 4% had pathologic N1 disease. Sixteen patients were categorized as high-risk based on the presence of sarcomatoid features (n = 4), pathologic N1 disease (n = 6), or both (n = 6). There were 22 recurrences; the recurrence rate in the low-risk group was 4.9% and 50% in the high-risk group. 10-year RFS was 91.4% in the low-risk group and 34.4% in the high-risk group (P < 0.001). 10-year CSS was 96.4% in the low-risk group and 54.3% in the high-risk group (P < 0.001). In multivariable analysis, sarcomatoid features (HR 5.5, CI 1.5-20.2, P = 0.01) and pN1 disease (HR 16.5, CI 5.3-51.4, P < 0.0001) were independently associated with RFS.

The presence of sarcomatoid features and/or lymph node-positive disease portends a poor prognosis in ChRCC. Further studies evaluating the impact of novel therapeutic agents in these patients are warranted.