CD133 immunohistochemical expression predicts progression and cancer-related death in renal cell carcinoma

Abstract

To evaluate the prognostic impact of the histological expression of CD133 in renal cell carcinoma (RCC). From 1992 to 2009, 142 consecutive patients underwent radical nephrectomy or partial nephrectomy for RCC. All cases were reviewed by a single pathologist and then subjected to analysis of the immunohistochemical expression of CD133 using tissue microarray. Several clinical and pathological variables were also evaluated. The median postoperative follow-up was 44months. Of the 142 immunostained RCC specimens, 77 (54%) showed low and 65 (46%) high expression of CD133. Expression of CD133 was associated with clinical stage (P=0.05), lymph node involvement (P=0.03), metastatic disease (P=0.02) and MVI (P=0.03). Among other variables, clinical stage, necrosis and metastasis were associated with disease-specific survival (DSS) and progression-free survival (PFS) on univariate analysis. The 5-year PFS rates in patients who provided specimens with high and low expression of CD133 were 83 and 66%, respectively (P=0.01). It was observed that the 5-year DSS for patients who provided specimens with high and low expression of CD133 was 90 and 71%, respectively (P=0.003). Multivariate survival analysis showed that patients in the CD133 low-expression group had a higher probability of disease progression (HR 3.4, P=0.02) and a higher probability of death from cancer (HR 2.4, P=0.01). Immunohistochemical expression of CD133 had an impact on survival in patients with RCC, which shows that CD133 might be a useful tool for risk stratification. Low expression of this marker remained as an independent predictor of poor DSS and PFS.