Differing form of variant form of hypergranular promyelocytic leukaemia (M3), or transition between M3 and monocytic leukaemia?

A 17-year-old woman had acute myeloid leukaemia (AML) with a leucocyte count of about 100 x 10(9)/1. The great majority of the leucocytes were immature. About half of them were without granules; in the other half the granules were usually scanty, but occasionally numerous and rather coarse. A few cells had Auer rods arranged in bundles. The patient had uncompensated disseminated intravascular coagulation (DIC) with a severe tendency to bleed. Everything fitted with variant hypergranular promyelocytic leukaemia, except for the staining of 30% of the immature cells by Löffler's unspecific esterase with alpha-naphthyl acetate. The patient may, therefore, be classified as either a variant of variant form M3, or as a transition between M3 and acute monocytic leukaemia.