A promyelocyte is a relatively large cell with a round or oval, eccentrically located nucleus in which one or more nucleoli can be seen. The cytoplasm is dark blue/purple with often a single brightening at the edge of the nucleus (golgi zone). The dark blue colored granules lie both in the cytoplasm and over the nucleus. The promyelocyte is the youngest variant of the granulocyte series that can still reasonably be seen in peripheral blood in severe infections. If many and/or abnormal promyelocytes are found, one should be wary of acute promyelocyte leukemia (APL).