This data confirms a conclusion that has already been well demonstrated by numerous others that have shown both substantial levels of tumor specific SFRP1 hypermethylation in RCC [16], [39]–[41] and that this methylation associates with higher grade and stage in tumors and predicts for poor prognosis in RCC patients [16], [40]. The gene discussed is SFRP1; the disease is renal cell carcinoma.