ACUTE LEUKEMIAS Flashcards
What is required for diagnosis of majority of acute leukemias
Finding at least 20% of blast ( blast cells are immature stem cells that give rise to different specialized cells)
What is acute lymphoblastic leukemia
Acute Lymphoblastic Leukemia (ALL) is a type of cancer that affects the blood and bone marrow.
What percentage of children diagnosed with ALL experience complete remission
- Children with ALL have a good prognosis Over 80% of pediatric patients are cured and the remission rate is 95%
Explain the chromosomal abnormalities of ALL
- Philadelphia chromosome is seen in about 20% of adults with ALL and 2% to 5 % of children with ALL
- t(4;11) translocation is commonly found in infants with ALL( t(4;11) means translocation between chromosome 4 and 11/genes transferred from gene 4 and 11)
How can the chromosome number in children be used to to predict the severity of ALL
Higher numbers of chromosomes have best prognosis for complete recovery with therapy. Greater than 50 chromosomes
- What is the significance of chromosome number in childhood ALL?
- The chromosome number is critical for predicting the severity of childhood ALL. Specifically, children whose leukemic cells contain more than 50 chromosomes have the best prognosis for complete recovery with therapy.
- How are recurring translocations observed in ALL associated with prognostic outcomes?
- Recurring translocations observed in ALL, such as t(4;11)(q21;q23), t(12;21)(p13;q22), and t(1;19)(q23;p13.3), are associated with prognostic outcomes.
- These translocations help determine patient therapy and play a crucial role in predicting the course of the disease.
Provide examples of recurring translocations observed in ALL and explain their implications on patient therapy.
- t(4;11)(q21;q23): Associated with the MLL gene, this translocation is often seen in infants and has a poor prognosis.
* t(12;21)(p13;q22): Commonly found in children, this translocation involves the TEL-AML1 fusion gene and is associated with a favorable prognosis.
* t(1;19)(q23;p13.3): Linked to the E2A-PBX1 fusion gene, this translocation occurs in adolescents and has an intermediate prognosis
Explain the importance of the subtype of ALL as a prognostic indicator for survival.
- The subtype of ALL is a significant prognostic indicator for patient survival.
- Different subtypes may have varying responses to treatment, affecting overall outcomes.
What are 3 things to look fro to rule out if the patient has leukemia
- Neutropenia
- Thrombocytopenia
- Anaemia
With reference to leukemia triad How to check if the patient has thrombocytopenia
The patient will have mucocutaneous bleeding
With reference to leukemia triad how to check for anaemia
Fatigue
With reference to leukemia triad how to check for neutropenia
Fever
What are the characteristics of ALL
- Lymphadenopathy ( disease of the lymph nodes in which they are enlarged)
- Splenomegaly and hepatomegaly (enraged spleen and enlarged river respectively)
- Bone pain
- Infiltration of malignant cells into meninges
What is lymphadenopathy, and how is it related to ALL?
Lymphadenopathy refers to the enlargement of lymph nodes. In the context of ALL, it is often a symptom due to abnormal proliferation of lymphoblasts in the lymph nodes.
Describe the symptoms of splenomegaly and hepatomegaly in patients with ALL.
- Splenomegaly: Enlargement of the spleen. In ALL, the spleen may become enlarged due to infiltration by leukemic cells.
- Hepatomegaly: Enlargement of the liver. Hepatomegaly can occur in ALL as malignant cells infiltrate the liver tissue.
Explain the cause of bone pain in patients suffering from ALL.
Bone pain results from the infiltration of leukemic cells into the periosteum (the outer covering of bones). This infiltration disrupts normal bone function and causes pain.
How do malignant cells infiltrate into the meninges, testes, or ovaries in ALL?
- Meninges: Leukemic cells can infiltrate the meninges (the protective membranes around the brain and spinal cord), leading to central nervous system involvement.
- Testes and Ovaries: ALL cells may infiltrate the testes or ovaries, affecting reproductive organs.
What are lymphoblasts, and where can they be found in cases of ALL?
Lymphoblasts are immature white blood cells (precursors to lymphocytes). In ALL, they proliferate abnormally. They can be found in the bone marrow, blood, and other tissues.
In cases of T-cell ALL, where might a mass be located within the body?
T-cell ALL can present with a mass in various locations, including the mediastinum (the area between the lungs), thymus, and other lymph nodes. It may also affect structures like the trachea and esophagus.
Outline the laboratory investigations of ALL
- Morphology
- Flow cytometric analysis
- Cytochemical stain
Explain the morphology of lymphoblasts in ALL investigations
- Small lymphoblast- the cost common type 1.0 to 2.5 times the size of a nomal lymphocyte scant blue cytoplasm and in distinct nucleoli
- Large lymphoblast- 2 to 3 times the size of a normal lymphocyte with prominent nucleoli and nuclear membrane
Morphological difference between a small lymphoblast and a large lymphoblast
- in lymphoblast has a loose chromatin ( there are many soaces) unlike in the large lymphoblast
- Lymphoblast has a small nucleus to cytoplasm ratio while large lymphoblast has a big nucleus to cytoplasm ratio
- What is the purpose of flow cytometric analysis in the context of laboratory investigation of ALL?
Flow cytometric analysis is used to identify and quantify specific cellular markers expressed by B cells and T cells. It helps characterize cell populations and diagnose diseases like acute lymphoblastic leukemia (ALL).
Which markers are generally expressed by B cells according to the image?
- General B cells express the following markers:
* CD19
* CD20
* CD24
* CD79a
* CD10
* Cytoplasmic µ (mu)
* PAX-5 (B-cell-specific activator protein)
What markers are expressed by blasts (immature B cells) as per the information in the image?
- Blasts express the following markers:
* CD19
* Cytoplasmic CD79a
* Cytoplasmic CD22
* Nuclear TdT (terminal deoxynucleotidyl transferase)