Acute Lymphoblastic Leukemia

INTRODUCTION:
  • 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.
PREDISPOSING FACTORS:
  • HEREDITARY
  • ACQUIRED
  • Ionizing radiations
  • Therapeutic radiations
  • Nuclear fallout
  • Diagnostic Xrays
  • Chemical agents
  • Viruses
SYMPTOMS:
  • FEVER
  • FATIGUE
  • BONE /JOINTS PAIN
  • WEIGHT LOSS
  • PURPURA AND BLEEDING MANIFESTATION
  • LYMPHADENOPATHY
  • HEPATOSPLENOMEGALY
  • STERNAL TENDERNESS
  • MEDIASTENAL MASS
FAB CLASSIFICATION:
  • ALL L1
  • ALL L2
  • ALL L3

  1. In childhood – L1 is the most common type
  2. In adults – L2 is the most common type

Morphology 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
WHO CLASSIFICATION:
  • B lymphoblastic leukemia/lymphoma nos
  • B lymphoblastic leukemia/lymphoma with recurrent abnormalities
  1. t( 9; 22) , BCR ABL1
  2. t( v; 11q23) MLL rearangement
  3. t (12;21) ETV6-RUNX1
  4. With hypodiploidy
  5. With hyperdiploidy
  6. t (5;14) il3 –igh
  7. t ( 1;19) E2A-PBX1 (tcf3-pbx1)
  8. T lymphoblastic leukemia/lymphoma
DIAGNOSIS:
  • Peripheral Blood smear:
  1. Total leucocyte count raised , normal or low.
  2. Normocytic normochromic anaemia.
  • Thrombocytopenia.
  1. Bone marrow aspiration smear:
  2. Hypercellular
  • Normal hematopoietic elements diminished
  • Cytochemistry
  • Immunophenotyping
  • Cytogenetic analysis
  • Molecular genetic analysis
  • Both myeloperoxidaes and nonspecific esterases are positive in cells of myeloid origin and are negative in cells­ of lymphoid origin
PROGNOSIS:
Factor 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 < 50000 >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.t (12 : 21) translocation
mmuno-phenotype B-ALL,CD 10+, Early pre-B cell T-ALL in children
Exam Question
  • Age of onset between 2-8 years,female, Early pre-B cell,Initial WBC count less than 50000 & Hyperdiploidy are good prognostic factor
  • t(9:22), t(8:14), t(4:11),t (12 : 21) translocation shows bad prognosis
  • Presence of mediastinal mass shows bad prognosis
Don't Forget to Solve all the previous Year Question asked on Acute Lymphoblastic Leukemia