Western blot analysis for the AML1/ETO fusion protein and fluorescent in situ hybridization (FISH) analysis for t(8;21) were performed in patients for whom we had samples.     ///    Western blot analysis showed the AML1/ETO fusion protein in four of the seven patients for whom we had samples among the eight with masked t(8;21) shown by RT-PCR.     ///    Comparison of outcome in acute myelogenous leukemia patients with translocation (8;21) found by standard cytogenetic analysis and patients with AML1/ETO fusion transcript found only by PCR testing..     ///    Five of 54 patients with NKAML had a detectable AML1/ETO fusion RNA transcript. 