Most of the ALLs have –
Correct Answer: B - cell origin
Description: Acute lymphoblastic leukaemia/lymphoma
Acute lymphoblastic leukaemia (ALL) encompasses a group of neoplasms composed of immature, precursor B (Pre-B) or T (Pre-T) lymphocytes referred to as lymphoblast.
The majority (85%) of all ALLs are precursor B-cell tumors that typically manifest as childhood "Leukemia" with extensive bone marrow and variable peripheral blood involvement.
The less common precursor T-cell ALLs tend to present in adolescent males as "lymphomas", often with thymic involvement.
The peak incidence of Pre B-cell ALL is evident between 3-5 years and ALL is the most common childhood cancer.
Pre T-cell ALL occurs in adolescent male.
Morphology of tumor cell (lymphoblast).
Having scant cytoplasm and nuclei somewhat larger than those of small lymphocytes.
The nuclear chromatin is delicate and finely stippled and nucleoli are either absent or inconspicuous.
Contain cytoplasmic aggregates of Periodic acid Schiff (PAS) positive material.
Clinical manifestations
Symptoms related to depression of normal marrow function.
An accumulation of neoplastic blast cells in the bone marrow suppresses normal hematopoiesis by physical crowding and competition for growth factors.
This results in : -
Anemia → Fatigue, pallor
Neutropenia → Infection, fever
Thrombocytopenia → Bleeding, petechiae, ecchymoses, epistaxis.
These are the most common sign & symptoms.
Bone pain tenderness
Resulting from marrow expansion and infiltration of the subperiosteal.
Generalized lymphodenopathy, Splenomegaly and hepatomegaly.
Caused by neoplastic infiltration of these tissues.
More common in ALL than AML.
Symptoms related to compression of large mediastinal vessels or airway.
In Pre-T ALL of thymus.
CNS manifestation
Due to meningeal involvement
A headache, vomiting, nerve palsies.
More common in ALL than in AML.
Testicular involvement is also more common in ALL than in AML.
Note
The FAB diagnostic criteria for acute leukaemia is the presence of > 30 blasts in bone marrow (normal < 5%).
According to WHO classification, blasts should be > 20% in bone marrow for diagnosis of acute leukaemia.
Category:
Pathology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now