ACUTE LYMPHOBLASTIC LEUKEMIA

LEUKEMIA

• Leukemia are the neoplastic proliferation of hemopoietic cells.

• Acute leukemias are defined as neoplsam • AML - more than 20 % blast• ALL- more than 25% blast.

• Commonest form of malignancy in childhood.• Peak incidence at 4 – 5 yrs of age.• Acute onset with short history of duration.• 85% are B cell , 15% are T cell.

ACUTE LYMPHOBLASTIC LEUKEMIA

• HEREDITARY

• ACQUIRED• Ionizing radiations• Therapeutic radiations• Nuclear fallout• Diagnostic Xrays• Chemical agents• Viruses

PREDISPOSING FACTORS

• Activation of a proto-oncogene to an oncogene when it is translocated to a transcriptionally active site

• Formation of a chimeric transcription factor• Formation of a fusion protein with enhanced tyrosine

kinase activity• Activation of FTL3 receptor• Inactivation of tumour suppressor gene pathway

MECHANISM OF LEUKAEMOGENESIS

SYMPTOMS• FEVER • FATIGUE• BONE /JOINTS PAIN• WEIGHT LOSS• PURPURA AND BLEEDING MANIFESTATION• LYMPHADENOPATHY• HEPATOSPLENOMEGALY• STERNAL TENDERNESS• MEDIASTENAL MASS

FAB CLASSIFICATION• Based on morphology and cytochemistry.• stain AML ALL

MPO + -

SBB + -

NSE + IN M4, M5 AND M7 -

PAS FINE + IN M6 , M7 + , BLOCK

ACID PHOSPHATASE - +, T ALL

FAB CLASSIFICATION

ALL L1 ALL L2 ALL L3

In childhood – L1 is the most common type In adults – L2 is the most common type

FAB classificationMorphology L1 L2 L3

1 Size of blast Small Large heterogeneous

Large homogenous

2 Cytoplasm Scanty Moderate Moderate, intensely basophilic

3 N/C Ratio High Lower Lower

4 Cytoplasmic vacuoles +/- +/- Prominent

5 Nuclear membrane Regular Irregular with clef ting

Regular

6 Nucleoli Invisible / indistinct

Prominent 1-2 Prominent 1-2

CRITICISM OF FAB CLASSIFICATION

1- It dose not include • Immunophenotyping• Cytogentics• Molecular characteristics2- immunological subtype of ALL3-biphenotypic leukemia4- Limited relevance to therapeutic or

prognostic implications.

WHO CLASSIFIACTION OF ALL (2008)

1-B lymphoblastic leukemia/lymphoma nos2- B lymphoblastic leukemia/lymphoma with recurrent

abnormalities• t( 9; 22) , BCR ABL1• t( v; 11q23) MLL rearangement• t (12;21) ETV6-RUNX1• With hypodiploidy• With hyperdiploidy• t (5;14) il3 –igh• t ( 1;19) E2A-PBX1 (tcf3-pbx1)3-T lymphoblastic leukemia/lymphoma

IMMUNOLOGICAL CLLASIFICATION

• 1- B ALL• PRO B ALL• EARLY PRE B ALL• PRE B ALL• MATURE B ALL• 2- T ALL• 3- MIXED LINEAGE ACUTE LEUKEMIA• 4-Undifferentiated acute leukemia

IMMUNOLOGICAL CLLASIFICATIONSUBTYPE HLA DR TdT CD 10 cIg smIg

Pro B ALL +_ + - - -

COMMON ALL + + + - -

Pre BALL + - - + -

Mature B ALL - - - - +

T ALL

• PAS negative acid phosphatase positive • CNS involvement and mediastenal mass• CD3 ,2 and 7 positive

Scoring system for biphenotypic leukemiapoints B lineage T lineage Myeloid

2.0 CD 79aCD 22.

CD 3 MPO

1.0 CD 10 CD 1 CD 13

0.5 TdT TdT, CD 7 CD 11bCD 11c

Score above 2 from two lineage is diagnostic of biphenotypic leukemia

Uncommon variants of ALL

• Small cell variant- blast cells are small and may be mistaken for lymphocytes.

• Hand mirror variants- a subtype with cytoplasmic protrusion .

• ALL with eosinophilia• Granular cell ALL- The cells are large and

demonstrate azurophilic granulaes .

Hand mirror variants

• Peripheral Blood smear• Bone marrow aspiration smear• Cytochemistry• Immunophenotyping• Cytogenetic analysis• Molecular genetic analysis

DIAGNOSIS OF ACUTE LEUKEMIA

PERIPHERAL BLOOD EXAMINATION

• Total leucocyte count raised , normal or low.• Normocytic normochromic anaemia.• Thrombocytopenia.

• Subleukemic leukemia-Total leukocyte count is normal or low , but blast are seen in the peripheral blood.

• Aleukemic leukemia- Blast are not seen in the peripheral blood , but are demonstrable only in bone marrow.

BONE MARROW EXAMINATION

• Hypercellular• Normal hematopoietic elements diminished

ALL L1

Size – small.Cytoplasm scanty basophilic.N/C Ratio – high.Nuclear membrane – regular.

Nucleoli – invisible or indistinct.

BONE MARROW SMEAR

BLAST

ALL L2

Size of blast – large & heterogenous Cytoplasm – moderate N/C Ratio – lower Cytoplasmic vacuoles – variable Nuclear membrane – irregular with clefting Nucleoli – prominent ,1-2

BONE MARROW SMEAR

ALL L3 Size of blast – large & homogenous Cytoplasm – moderate & intensely basophilic N/C Ratio – lower Cytoplasmic vacuoles – prominent Nuclear membrane – regular Nucleoli – prominent , 1-2

BONE MARROW SMEAR

LYMPHOBLAST WITH CYTOPLASMIC VACUOLES & NUCLEOLI

STARRY SKY PATTERN

PAS STAIN

LYMPHOBLAST WITH BLOCK & COARSE GRANULAR STAINING

STAINS

METHYL GREEN PYRONINE OIL RED O(VACUOLES)

• Diagnosis and classification.• Assessment of prognosis.• Monitoring of minimum residual disease.

IMMUNOPHENOTYPING

• Establishment of lineage-DNA analysis.• Identification of translocation.• Detection of relapse.• Detection of minimum residual disease.

Molecular Genetics-

OTHER INVESTIGATIONS• Lumbar puncture.• Testicular biopsy.• X-Ray chest.

DIFFERENTIAL DIAGNOSIS

• Leukemic phase of Non Hodgkins Lymphoma• Reactive lymphocytosis due to infections• Metastatic tumours in bone marrow• AML

ALL Vs AMLALL AML

Age Mainly children Mainly adults

Lymphadenopathy Usually present Usually absent

Hepatosplenomegaly +ve mild +ve mild

Gum hypertrophy -ve +ve in M4/M5

Skin infiltration -ve +ve in M4/M5

CNS involvement +ve in some +ve in some

Granulocytic sarcoma -ve +ve in few cases

Mediastinal mass +ve in T-ALL -

Associated DIC -ve +ve in M3

Serum muramidase Normal In M4/M5 (monocytic type)

Prognosis Good Bad

MorphologyLymphoblast Myeloblast

Nuclear chromatin Coarse Fine

Nucleoli 1-2 3-5

N:C ratio High High

Auer rod -ve +ve

Accompanying cells

Lymphocytes Myeloid precursor

Myelo peroxidase -ve +ve

Sudan Black B -ve +ve

PAS stain Block positivity -ve in blast

AML ALL

PROGNOSTIC FACTORSFactor Good prognosis Bad prognosis

Race White Black

Age 2-8 yrs <1yr.,adult, >10 yrs

Sex Female Male

Meningeal involvement - +

Lymphadenopathy, liver, spleen

- Massively enlarged

Mediastinal mass - +

TLC <20x109 /L >50 x109 /L

Type of ALL L1 L2,L3

Cytogenetics Hyperdiploidy >50 chromosomes

Pseudodiploidy, t (4;11),t (9;22), BCR-ABL fusion m RNA, MLL-AF4 fusion mRNA.

Immuno-phenotype B-ALL,CD 10+, Early pre-B cell

T-ALL in children

Minimal residual disease detection

– ALL – B cell– Cd20/cd10/cd19/cd45– Cd9/cd34/cd19/cd45– Cd58/cd10/cd38/cd19– Cd20/cd10/cd19/cd34– ALL –T cell– TdT/CD5/CD3/CD7

• MODERATOR— Prof. Dr. C. V. KULKARNI

• SPEAKER- DR. NARMADA PRASAD TIWARI

• AML• CD34/CD33/HLA-DR/CD45• CD34/CD117/CD33/CD45• CD115/CD117/CD33/CD34• HLA-DR/CD117/CD33/CD34

• CLL• CD20/CD79a/CD19/CD5

Factors Predisposing to Childhood Leukemia

• GENETIC CONDITIONS Down syndrome

• Fanconi syndrome • Bloom syndrome • Diamond-Blackfan

anemia • Schwachman syndrome • Klinefelter syndrome • Turner syndrome

• Neurofibromatosis • Ataxia-telangiectasia • Severe combined

immune deficiency • Paroxysmal nocturnal

hemoglobinuria • Li-Fraumeni syndrome

• ENVIRONMENTAL FACTORS• Ionizing radiation • Drugs • Alkylating agents • Nitrosourea • Epipodophyllotoxin • Benzene exposure • Advanced maternal age