Positivity for calretinin, in conjunction with at least one other marker from this panel, is diagnostic for UTROSCT, whereas ESTSCLE generally express a single sex-cord marker, predominantly calretinin; this may be due to the sex cord elements in ESTSCLE constituting a minor part of the tumor and lacking the great variety of histological features observed in UTROSCT [3]. The gene discussed is CALB2; the disease is neoplasm.