In line with the latter, Carney et al6 emphasized that PAX2 and Inhibin-α were the best markers for this differential diagnostic purpose and that PAX8 had to be used as the second ccRCC marker, as its use increased the diagnostic sensitivity for metastatic ccRCC from 88% to 94%, without changing the specificity and the positive predictive value.6 Other authors reported that CD10 is a good marker for distinguishing between HB and metastatic ccRCC, being consistently negative in all HB cases.16 The gene discussed is MME; the disease is hemoglobin measurement.