Acute Leukemia - PDF

ACUTE LEUKEMIA Head of department Dr Mihaela Andreescu UTM – Faculty of Medicine  Pluripotent stem cell...

ACUTE LEUKEMIA Head of department Dr Mihaela Andreescu UTM – Faculty of Medicine  Pluripotent stem cell SCF Multipotent Multipotent myeloid IL3, GM-CSF IL3 lymphoid stem cell stem cell IL3, IL11,TPO IL3, EPO IL3, GM-CSF IL3, IL7 SCF Proerythroblast Mieloblast Limfoblast Megakaryoblast IL11, EPO TPO IL3, GM-CSF IL3, GM-CSF IL3, GM-CSF IL3, IL7 Basophilic erythroblast B. promyelocite N. promyelocite E. promyelocite Monoblast GM-CSF, IL4 GM-CSF, GM-CSF, Promegakryoblast G-CSF IL5 GM-CSF, EPO M-CSF IL6, TPO Polychromatic erythroblast B. myelocytes N. myelocytes E. myelocytes Prolymphocyte IL4 G-CSF Promonocyte IL5 IL2, IL7 Erythroblast oxyfill B. metamielocit N. metamyelocite E. metamyelocite M-CSF Megakaryocyte NK cell Small lymphocyte IL2, IL6, Reticulocytes IL4, TPO B. band N. band E. band IL7 B lymphocyte T-lymphocyte IL6 Platelets Erythrocytes Basophile Neutrophil Eosinophil Monocyte LTh LTc Macrophage Dendritic Dendritic Mastocyte myeloid cell Plasmocyte lymphoid cell  MYELOID LINEAGE MATURATION myeloblast promyelocyte myelocyte metamyelocyte band neutrophil MATURATION Adapted and modified from U Va website  LEUKEMIA Blood cancer; Acute or Chronic; Affects body's ability to produce mature, normal cells; The bone marrow produces abnormally large immature cells, cells with very young cell characters – called blast cells. Acute leukemia  Acute leukemia Acute leukemias (AL) are a heterogeneous group of malignant diseases of undifferentiated or partially differentiated hematopoietic stem cells. Incidence – 3-5 cases /100.000 inhabitants / year – male predominance +Median age: 62-65 years for AML; 30-40 years for ALL Acute leukemia = Blast accumulation in the bone marrow  The term "acute" means that the disease progresses rapidly. In acute leukemias, which develop rapidly, cancer cells are immature and unable to perform their functions (immune system).  Risk factors for acute leukemia ▪ Accidental exposure ▪ Benzene Professional exposure Arsenic Therapeutic exposure Phenylbutazone Chloramphenicol Alkylated agents Topoisomerase II inhibitors Ionizing radiations +Chemicals and medicines ▪ Acquired aplastic anemia +Medullary hypoplasia Anemia Fanconi Paroxysmal nocturnal hemoglobinuria +Genetic factors +Viral agents ▪ Down syndrome Fanconi syndrome Bloom syndrome ▪ HTLV1(retrovirus )=> Adult T-cell Klinefelter syndrome leukemia/lymphoma Hereditary ataxic telangiectasia  Acute leukemia pathogenesis: Malignant clonal transformation +Proliferation of immature cellular population without physiological function Hematopoiesis in leukemia: - monoclonal - blocking in maturation / differentiation uncontrollable Result of the expansion of leukemia population: ▪ Bone marrow infiltration = > bone marrow insufficiency Extramedullary blast infiltration of tissues and organs  Mechanism of leukemia transformation 1. ONCOGENES Extracellular growth factors sis Membrane associated tyrosine-kinase fms, kit, erb-B Intracellular signal transduction: a.) binds GTP H-ras, K-ras, N-ras b.) serine / treonine kinase raf, mos c.) nuclear - transcription factors jun, fos, myc, myb, - receptors for vitamins/hormones ets, - tyrosine- kinase erb-A, RARA-α abl 2. TUMOR SUPPRESSOR GENES p53, Rb 3. APOPTOSIS INHIBITORS bcl-2  Signs and symptoms in acute leukemia At the onset of the disease: fever, fatigue, loss of appetite. Other symptoms may include: bone pain; frequent nose bleeding; gum bleeding and swollen gums; easy bruising – caused by a very low platelet count (thrombocytopenia), which may also include the appearance of red spots on the skin called petechiae; profuse sweating – especially at night; shortness of breath; unexplained weight loss; menorrhagia; enlargement of spleen and liver.  ACUTE LEUKEMIA DIAGNOSIS Cytological examination (PB/BM ) Standard cytochemical examination Ultrastructural cytochemistry +Examination of surface and intracytoplasmic markers = flow cytometry +Cytogenetics and molecular biology  CLASSIFICATION Subsequently, a complete characterization of the different stages of maturation was performed, both on AL types are differentiated depending the lymphoid and myeloid lines. For on the proliferating cell population, this purpose, in addition to the clinical manifestations, evolution and morphological analysis of leukemia therapeutic response. cells, cytochemical, immunophenotypic, cytogenetic, molecular biology techniques were used.  The FAB classification describes the degree of differentiation of leukemia cells based on the FAB CLASSIFICATION morphological aspect. For positive diagnosis (The French-American-British (FAB) and subtype determination, bone marrow classification of AL) examination is indispensable. Acute lymphoblastic leukemia (ALL) ) AL diagnosis is established when blast cells Acute myeloid leukemia (AML ) percentage is > 30% of the total bone marrow nucleated cells. Acute leukemia  Acute lymphoblastic leukemia (ALL) Cytological: L1 L2 L3 ACUTE LEUKEMIA CLASSIFICATION Immunophenotypic: Commune ALL ( CALLA +) B ALL ( Burkitt like) T ALL ALL null  ACUTE LEUKEMIA CLASSIFICATION Acute myeloid leukemia (AML ): - Minimally differentiated AML(AML-M0 ) - AML without maturation(AML-M1 ) - AML with maturation (AML-M2 ) - Promyelocytic AL (AML-M3 / LAP ) - Mielomonocytic AL (AML-M4 ) - Monocytic AL (AML-M5 ) - Erythroleukemia (AML-M6 ) - Megakaryblastic AL (AML-M7 )  The FAB classification recognizes 3 subtypes of acute lymphoblastic leukemias (ALL), defined on the basis of the morphological characters of lymphoblasts (cell size, appearance of nuclear chromatin, shape of the nucleus, appearance of nucleoli, amount of cytoplasm). L1 – homogeneous lymphoblastic population, with small cells (double size of normal lymphocytes) with an increased nucleo-cytoplasmic ratio. It Acute lymphoblastic represents 80% of the ALL in children and only 30% of ALL in adults. leukemia L2 –more heterogeneous cell population- in size and appearance, with larger cells as in L1; irregular nucleus, with more heterogeneous chromatin, one or more prominent nucleoli. Represents 67% of ALL in adults and only 18-20% of cases in children. L3 (Burkitt type, with cells similar to those of Burkitt lymphoma) – large cells with regular nucleus, stippled homogenous chromatin structure, large nucleoli; abundant cytoplasmatic vacuolation (bubble type), intense basophilic cytoplasm. It is the rarest form (less than 3% of cases) and has poor prognosis. ALL-L2 (Marrow) ALL-L3 (Marrow)  The FAB classification system (1976), based on morphological and cytochemical criteria recognizes 8 subtypes of acute myeloblastic (AML) or non- lymphoblastic leukemias. M0 (AML without maturation, 2-3% of cases) – large agranular blast population that can Acute myeloblastic sometimes be confused with those in ALL 2. The diagnosis cannot be established in optical leukemia microscopy (OM), but only on the basis of demonstrating the presence of cytoplasmatic granulations in electron microscopy (EM), of the expression of myeloid surface antigens (CD13, CD33, myeloperoxidase), as well as the absence of antigens specific to the lymphoid line.  M1 (AML with minimum maturation, 20% of cases) – blast population (80-90% of non-erythroid cells) represented by large myeloblasts with rare fine azurophilic granulations; in half of the cases the Auer rods are present. Positive diagnosis is established if >3-5% of cells have positive myeloperoxidase or black Sudan black stain. Acute myeloblastic M2 (AML with maturation, 20-25% of cases) – leukemia about 30-80% of the non-erythroid cells are well differentiated myeloblasts, with rich cytoplasm, with variable number of azurophilic granulations; in 65% of cases auer rods are present and in 10% of cells the maturation exceeds the blast stage. Intense positive reaction for myeloperoxidase Sudan black stain.  M3 (Promyelocytic acute leukemia, 8-15% of cases) – myeloid population is dominated by the presence of promyelocytes (pathological), large cells with a round or deep cleft nucleus, abundant cytoplasm with numerous azurophilic granulations, larger than normal, with Auer bodies that appear in bundles, often covering the nucleus. Very intense myeloperoxidase reaction. There is also a microgranular variant (20-25% of M3) – cells with irregular, bilobed, reniform or similar to monocytic nucleus; the Leucemiile acute cytoplasm contains granulations. Although it can be confused with M5, cytogenetic, cytochemical and ultrastructural analyses allow the mieloblastice classification of this form in M3. M4 (Myelomonocytic leukemia, 20-25% of cases) – in the marrow are present precursors of granulocytic and monocytic lines in variable proportions, each line representing >20%, but not >80% of nucleated cells. Myeloblasts contain Auer rods. Monoblasts are larger than myeloblasts, with round/ovalar nucleus, with immature, dispersed chromatin, obvious nucleoli, abundant cytoplasm, with azurophilic granulations. There are an increased number of monocytes and promonocytes in the blood. The diagnosis is completed by cytochemistry, with reactions for myeloperoxidase, specific and nonspecific esterases. Acute promyelocytic leukemia - peculiarities: - cytological ➔ AUER rods - biological => DIC - Cytogenetic => t 15:17 (q22:q21) => PML / RAR alpha oncogene  M5 (Acute monoblastic leukemia, 5% of cases) – monoblasts, promonocytes and monocytes represent 80% of non-erythroid cells.It has negative myeloperoxidase stain, with intensly positive nonspecific esterase reaction. There are two variants: M5a – 80% of the monocytic cells are monoblasts, with a nucleus with granular chromatin and abundant, basophilic, agranular cytoplasm. M5b – monoblasts are in smaller number, 20% of the cells have Leucemiile acute maturation, having kidney shaped nuclei, blue-gray cytoplasm with granulations. mieloblastice M6 (Acute erythroleukemia, 5% of cases) – erythrocytic precursors represent >50% of bone marrow nucleated cells, being characterized by megaloblastic changes and nuclear anomalies, similar to those in myelodysplasia. Over 20% of the nucleated cells are myeloblasts (blasts < 20% is considered to be a myelodysplastic syndrome). Auer rods can be encountered in 2/3 of the cases. Cytochemical- erythroblasts are positive for PAS and esterase. It is also described a form of pure erythroleukemia, without the presence of myeloblasts in the bone marrow.  M7 (Acute megakaryocytic leukemia, 1 % of cases) – large number of megakarioblasts with various stages of differentiation: undifferentiated forms, smaller size, nucleus with dense, homogeneous chromatin and hardly visible nucleoli, with reduced cytoplasm, or differentiated forms, larger size, with Acute myeloblastic granular chromatin, abundant cytoplasm leukemia with azurophilic granulations. It is associated with increased reticulin fibers, with difficult bone marrow aspiration. In general, the diagnosis requires cytochemical, immunophenotypic examinations (the presence of specific markers) and ultrastructural (the presence of platelet peroxidase)  Investigaţii paraclinice Hemograma hyperleukocytosis (60%; GA>10,000/ signs of bone marrow sometimes appears with mm3 in