Part 1 Myelodysplastic/Myeloproliferative

• it is the abnormal development of cells in the bone marrow leading to dysplasia and cytopenia of one or more cell line caused by predomination of apoptosis.

  Myelodysplastic
• An uncrontrolled proliferation of the cells in bone marrow leading to cytosis of one cell line, usually in myeloid lineage. Proliferation outspaces apoptosis

  Myeloproliferative
• asynchronous cell maturation resulting to abnormal cell size

  hypercellular maturation
• abnormal development of cells within tissues or organs that does not cause cell maturation in the circulation leading to cytopenia

  dysplasia
• a decrease in the number of cells, originated from the dysplastic development

  cytopenia
• it is the uncontrolled proliferation of the cells

  cytosis
• form of programmed cell death

  apoptosis
• Clinical definition:

  1. MDS is a pre-malignant process
  2. CMPD is a malignant disease
• Affected cell lines:

  • There are one or more cell lines are dysplastic in MDS. All cell lines are malignant in CMPD.
• Bone marrow cellularity in MDS are usually slightly increased and usually markedly increased in CMPD
• Resulting peripheral cell population in MDS is peripheral cytopenia in one or more cell lines while CMP is peripheral cytosis of usually one cell line.
• Peripheral blood evaluation in MDS has a dysplasia of one or more cell line, while CMPD are morphologically usually normal
• irone stores in MDS are often increased and in CMPD, they are normal/decreased
• Bone marrow fibrosis in MDS is usually none but in CMPD it has a prominent feature in the course of disease
• Megakaryocyte population in MDS is usually no increased in the bone marrow but in CMPD it is often increased in numbers
• Splenomegaly is not feature in MDS but in CMP it is a frequent feature.
• An infiltration of cells in bone marrow

  Fibrosis
• • a group of disorders that result from clonal abnormalities of hematopoeitic pluripotential stem cells.
  • characterized by progressive cytopenia, deffective erythroid, myeloid and megakaryocytic maturation
  • AKA as Pre-Leukemia - may lead to AML to ALL


  myelodysplastic syndrome
• age that are usually effect by MDS.

  >50 years old / 50-70 years old
• What cells are seen in peripheral blood when a person has MDS?

  Cytopenia
• What cells are presence in myeloid cell lines when a person has MDS?

  Dysplasia
• since only few of the tissues are producing WBCs, so the cytopenia is particularly more on leukopenia
• Clinical course/Progression of MDS

  • shorter than CMPD and longer than acute leukemia
• what test is use if a patient have MDS?

  chemotherapy or readiotherapy
• a pre-cursor cell that is once immediately release by the BM and begin to proliferate/accumulate in the circulation, it will lead to leaukemia.

  myeloblast
• Types of MDS:

  1. Primary MDS - caused by bone marrow
  2. Therpy-related MDS - develop after treatment with chemotherapy or radiothrapy