1. Malignant hematopoiesis (1)
Myeloproliferative disorders
Emanuel Nečas

2. Introduction

3. Myelopoiesis and Lymphopoiesis

4. Myelopoiesis and Lymphopoiesis
myeloid cells (erythropoiesis, granulocytopoiesis, monocytopoiesis, thrombocytopoiesis _ megakaryocytes)
lymphoid cells (B-lymphopoiesis,
T-lymphopoiesis, NK-lymphopoiesis)

5. Lymfoproliferative disorders
Myeloproliferative disorders
Lymfoproliferative disorders

6. Myeloproliferative disorders
- chronic
- acute
Lymfoproliferative disorders

7. Lymphoproliferative diseases can also have a form of a solid tumor, a lymphoma. Though seemingly localized to a lymphoid tissue outside the bone marrow, it is considered to be a systemic disease involving (infiltrating) the bone marrow regularly.

8. A single leukemic stem cells starts the disease
A single leukemic stem cells starts the disease. The disease then spreads throughout the body.

9. Malignant hematopoiesis
is usually monoclonal
is usually systemic

10. Normal hematopoiesis is polyclonal

11. Origin of the normal polyclonal hematopoiesis is in embryogenesisD E F G F H

12. Malignant hematopoiesis is monoclonal (examples: acute myeloid leukemia; AML)

13. random X-inactivation
XpXm
XpXm
female
somatic cells
XpXm
Embryogenesis
random X-inactivation Xm Xp
Clonal Event Xp Xp Xm Xm Xp Xp Xp Xp Xm Xm Xm Xm
Normal female somatic cells contain 2 X chr--1 maternally and 1 paternally derived. During embryogenesis, 1 X -xhr is randomly inactivated in each cell and this same pattern of inactivation is passed on to the progeny of each cell.
Thus, Females heterozygous for polymorphic X-chr genes are mosaics with respect to X-chr activity--this has been exploited for studies of clonality
If a clonal event occurs, all the cells will have the same active X-chr
X-inactivation occurs early during embryogenesis--exact timing unknown, but complete by late blastocyst stage
G6PD isozyme analysis 1st clonality assay based on X-inactivation
used to demonstrate clonality of leiomyomas, teratomas (~1965)
Most human cancers analyzed by G6PD are monoclonal:
breast, colon, cervical, ovarian teratomas, many hem neoplasms Xp Xp Xp Xp Xp Xp

14. Malignant monoclonal hematopoiesis is caused by mutations (F´cell clone)

15. Possible therapy outcomes
Treatment eliminates or supresses the malignant clone and normal polyclonal hematopoiesis usually resumes
Possible therapy outcomes
remission
successful treatment (complete remission)
residual disease
relaps

16. A pathological dominant clone may start from
a mutated hematopoietic stem cell
but not necessarily.
A mutated progenitor cell
may be a source of
a dominant malignant clone as well.

18. Normal bone marrow and CML, AML, CLL

19. Chronic myeloproliferative disorders

20. Chronic myeloproliferative diseases
Myelodysplastic syndrome (MDS)
Polycythemia vera rubra
Chronic myeloid leukemia (CML)
Essential throbocythemia
Idiopathic Myelofibrosis/or Agnogenic Myeloid Metaplasia
Chronic lymphocytic leukemia (CLL) …is lymphoproliferative disease

21. Myeloproliferative Disorders

22. Myeloproliferative Disorders (chronic)
Myelodysplastic syndrome - …“pre-leukemia“
Polycythemia Vera
Essential Thrombocythemia
Agnogenic Myeloid Metaplasia with Myelofibrosis (Idiopathic Myelofibrosis)
Chronic Myelogenous (Myeloid) Leukemia - CML

23. (Chronic) Myeloproliferative Disorders – common features
Acquired mutation in a hematopoietic stem cell
Clonal hematopoiesis
Proliferation of granulocytes, red cells and/or platelets
Splenomegaly (variable)
Bone marrow fibrosis (variable)

24. Myelodysplastic syndrome (MDS)

26. Myelodysplastic syndrome (MDS)
MDS is a myeloproliferative disease,
used to be called „preleukemia“
It has several forms.
There is decreased number of „myeloid“ cell in the blood (anemia, granulocytopenia, thrombocytopenia = pancytopenia)

27. Normal and dysplastic (MDS) bone marrow
Normal bone marrow
Dysplastic bone marrow

28. Dysplastic bone marrow in the RAEB (refractory anemia with excess of blasts) a form of the MDS

31. MDS – etiopathogenesis and conversion into AML
Altered
immune response
Altered
marrow stroma
Altered
cytokine response
Radiation
Oxidative
stress
Increased
apoptosis
Clonal
myelo-
poiesis
Stem cell
mutation
Clonal
evolution
Age
AML
Ineffective
haemopoiesis
T-cell
attack
Chemicals
Additional mutations/epigenetic changes 31

34. Polycythemia vera rubra („primary polycythemia“, Disease Vasquez-Osler)

35. Polycythemias
The first question to address is whether patient with elevated hematocrit has an absolute or “true”polycythemia or a relative polycythemia
Relative Polycythemia
Decrease in plasma volume; normal RBC mass
Spurious or stress polycythemia; Gaisbok’s disease
Seen in smoker’s, pts on diurectics
In contrast, pts with an abosolute or true polycythemia have an increase in red cell mass
Hct
43%
53%
53%

36. Polycythemia Vera
An acquired mutation of hematopoietic single stem cell
The nature of the disease causing mutation not known till 2005
– most cases have mutation in
the JAK2 tyrosinkinase

37. Polycythemia vera, Essential trombocythemia, Idiopathic myeolofibrosis

38. Incidence of Polycythemia Vera
Frequency, %
The prevalence of ET with age between men and women is shown here.1
Until the age of 76 years, disease is more common in men than in women. This trend changes as the population gets older, with women tending to live longer than men.
The incidence of the disease is 1:1.8 in favor of women.
1Jensen MK, de Nully Brown P, Nielsen OJ, Hasselbalch HC. Incidence, clinical features and outcome of essential thrombocythaemia in a well defined geographical area. Eur J Haematol 2000, 65(2):
Age

39. Cumulative Survival on Study (PV)
1.0
0.8
0.6
0.4
0.2
0.0
Cumulative survival
Phlebotomy
Chlorambucil
32P
The outcome of another study is depicted here. Patients were treated with chlorambucil, phlebotomy, or 32P. Those treated with phlebotomy alone did the best, whereas those treated with chlorambucil did the worst.11
The question is, why are these curves separating at about 300 weeks on this graph?
11Berk PD, Goldberg JD, Donovan PB, Fruchtman SM, Berlin NI, Wasserman LR. Therapeutic recommendations in polycythemia vera based on Polycythemia Vera Study Group protocols. Semin Hematol 1986, 23(2):
Time in weeks

40. Polycythemia vera causes of death (expressed as percentage)
Total number deaths
Phlebotomy 53
Chlorambucil 82
32P 79
Total
214
Thrombosis
17.2
13.5
44.2
Hemorrhage
0.0
4.3
3.8
8.1
Leukemia/Lymphoma
1.5
20.6
11.5
33.6
Cancer
4.5
9.9
9.6
24.0
Spent/MF
0.7
2.1
1.3
4.1
Other
15.7
7.8
10.9
34.4
NHL occurred only on the Chlorambucil arm

41. Sensitivity of BFU-E to Epo
100%
PV (EEC)
75%
PFCP
50%
Normal
EEC
25% 0% 30 60
125
250
3000
EPO (mU/ml)

42. Essential thrombocytemia

43. Essential Thrombocythemia
Platelet count in excess of 600,000 per mm3
Marked megakaryocytic hyperplasia
Abundant platelet clumps

44. Essential Thrombocythemia
No cytogenetic abnormalities
Splenomegaly seen in fewer than 50%
Morbidity: Thrombotic and/or bleeding problems

45. Essential Thrombocythemia
No cytogenetic abnormalities
The same
mutation in the JAK2 kinase
as causes Polycythemia vera is present in some patients

46. Idiopathic Myelofibrosis/ Agnogenic Myeloid Metaplasia

47. Idiopathic Myelofibrosis/ Agnogenic Myeloid Metaplasia (AMM)
Must exclude other causes of bone marrow fibrosis
“Spent phase” of PV or ET
CML
Hairy cell leukemia
Lymphoma
Metastatic cancer

48. Chronic myleoid leukemia (CML)

49. Chonic Myelogenous Leukemia
Proliferation of granulocytes
All stages of granulocyte maturation in peripheral blood
Platelets may be elevated
Polycythemia is rare
Splenomegaly, may be massive
Invariable transformation to acute leukemia
CML PB
Marked leukocytosis due to increased numbers of myeloid cells in all stages of maturation.
Basophils may also be present

50. This slide is to direct attention on the most important finding in this case. That is the massive splenomegaly which extends to the pelvic brim and across the midline. In addition hepatomegaly is present.
So in order to make a diagnosis, we need to focus on the causes of splenomegaly.

51. Our patient has massive splenomegaly
Our patient has massive splenomegaly. This shows a splenectomy specimen from a patient with massive splenomegaly. This spleen weighed 10 kg, or 22 pounds.

52. Philadelphia (Ph-) chromosome causes a majority of cases of CML
The ABL and BCR genes reside on the long arms of chromosomes 9 and 22, respectively. As a result of the (9;22) translocation, a BCR-ABL fusion gene is formed on the derivative chromosome 22 (Philadelphia chromosome).

53. Abnormal BCR-ABL fuse gen and BCR-ABL proteinkinase

55. Ciba-Geigy started to develop inhibitors of tytrosinkinases 30 years ago

56. Imatinib binds to BCR/ABL kinase instead of ATP

57. Přežití nemocných s CML při různé léčbě

58. „Targeted“ therapy – aimed at the biological cause of a disease
Imatinibem (Gleevec) suppresses cells belonging to mutated tumor clone – but does not get rid-off the body of the cause (all mutated cells).

59. Lasker prize for clinical research 2009
Brian J. Druker
Nicholas Lydon
Charles L. Sawyers

60. Mutations of the ABL kinase cause resistence against imatinib

61. Possible outcomes of CML
complete remission
residual disease
relaps
resistance to therapy
blastic conversion (AML)

62. Targeted therapy with imatinib is very effective

63. Important events in CML outlined

64. Acute myeloproliferative diseases
Acute myeloid leukemia (AML), several forms
(myelogenous, myeloblastic are synonyms to myeloid)
Acute lymphocytic leukemia (ALL) … is lymphoproliferative disease
(lymphoblastic is a synonym to lymphocytic)

65. Acute myleoid leukemia (AML)

66. Leukemic blasts present in blood

67. Leukemic blasts are present in bone marrow

68. Karyotype of the major clone from the relapse acute myeloid leukemia (AML)

69. Acute Myeloid Leukemia (AML)
- 8 clinical forms

70. AML subgroups – FAB classification

71. „Ziskové“ mutace receptoru Flt3 u akutní myeloidní leukémie (u 1/3 nemocných)

72. FLT3-ITD (internal tandem duplication)

73. Different AML types differ in prognosis

74. Flt3 receptor mutated in 40% of AML cases

75. FLT3-ITD (internal tandem duplication)

76. Acute promyelocytic leukemia (APL) _ M3
APL – promyelocytes do not mature into granulocytes
Normal bone marrow

77. Chromosomal translocation in APL results in abnormal – PML-RARα protein

78. Acute promyelocytic leukemia (APL)_M3
ATRA = all-trans retinoic acid overcomes defect of RARα protein and induces maturation of pathological promyelocytes =
„targeted therapy“ induce remission of the disease

79. „causative therapy“ for AML
Transplantation of hematopoietic stem cells („Bone Marrow Transplantation“)
is the only
„causative therapy“ for AML

80. END
OF THE LECTURE