Some cases of AML show blasts with prominent nuclear invaginations (NI), so called cup-like (CLB) or fish mouth blasts 1 due to indentation of the nucleus by bits of cytoplasm. The typical morphology is shown in Fig. 1. The blasts are medium-sized and have moderate cytoplasm with few fine azurophilic granules. The involved nuclear area shows a brighter color than the unaffected chromatin (Pappenheim staining, blood smear).
Some cases of AML show blasts with prominent nuclear invaginations (NI), so called cup-like (CLB) or fish mouth blasts 1 due to indentation of the nucleus by bits of cytoplasm. The typical morphology is shown in Fig. 1. The blasts are medium-sized and have moderate cytoplasm with few fine azurophilic granules. The involved nuclear area shows a brighter color than the unaffected chromatin (Pappenheim staining, blood smear).