The myeloid stem cells begin with myeloblasts or myelocytes
, which are immature blood cells found only in the bone marrow, then further differentiate into more mature cells (such as the erythrocytes or red blood cells [RBCs]) and polymorphonuclear granulocytes (such as neutrophils, eosinophils, and basophils), monocytes, and platelets (Guyton & Hall, 2000).
Morphologic Features of t(8;21) and inv(16) Acute Myeloid Leukemia t(8;21) inv(16) * Large myeloid blasts with * Variable number of eosinophils abundant basophilic cytoplasm * Numerous azurophilic granules * All stages of eosinophilic maturation * Perinuclear clearing or hofs * Immature purple-violet cytoplasmic granules * Occasional blasts containing * Mainly evident at the Auer rods promyelocyte and myelocyte
stages Table 2.
9]/L, which included 8% blasts, 51% myelocytes
and metamyelocytes, 24% neutrophils, 16% lymphocytes, and 1% basophils.
The control patients demonstrated a slightly higher percentage of myelocytes
than did the patients with MDS (P [is less than] .
Consecutive phases vary, giving rise to a kinetically distinct mitotic pool in which numbers expand to include the myeloblasts, progranulocytes and myelocytes
- loosely referred to as the fixed components of the microenvironment.
9]/l (check every 2 weeks until Basophils <5% CHR, then 3-monthly) No myelocytes
, promyelocytes, myeloblasts in the differential count Platelet count <450x[10.
Most of the increases were caused by an increase in polymorphonuclear cells (PMN), but seven of nine subjects demonstrated myelocytes
, a potentially clairvoyant observation given recent evidence that circulating stem cells increase after exercise (74).
Cells were pre-classified into: band neutrophils, segmented neutrophils, lymphocytes, monocytes, eosinophils, basophils, metamyelocytes, myelocytes
, promyelocytes, blast cells, lymphocyte variant forms and plasma cells.
There was abnormal maturation of the myeloid lineage with an expanded mitotic pool (6% myeloblasts) and markedly increased numbers of promyelocytes and myelocytes
The term chloroma comes from the green color of the immature myelocytes
that are imparted by the enzyme myeloperoxidase in the cytoplasm.
8 White cell count (per mL) 21,300 Differential count (%) Neutrophils 31 Lymphocytes 45 Bands 12 Myelocytes
4 Metamyelocytes 2 Reactive lymphocytes 5 Platelet count (per mL) 156,000 Prothrombin time (s) 25.
Wright staining of a bone marrow smear showed large (2-4 [micro]m) round-to-oval, hyaline-structured eosinophilic granules (pseudo Chediak-Higashi [PCH] granules) within 15% of the blast cells, promyelocytes, and myelocytes