White blood cell disorders

Question 1

Subclasses of ALL and their surface markers

Answer 1

B-ALL
- CD 10, CD19, CD20
T-ALL
- CD2-8 (eg CD3, CD4, CD7), no CD 10

Question 2

2 types of translocations in B-ALL

Answer 2

t(12;21) - children, good prognosis

t(9;22) - adults, poor prognosis

Question 3

Pathophysiology + Rx of Acute promyelocytic leukemia

Answer 3

t(15;17) - translocation of retinoic acid receptor (RAR) on chromo 17 to 15 - blocks maturation - promyelocytes accumulate
Rx- all-trans-retinoic acid (ATRA)

Question 4

Why is acute APL a medical emergency?

Answer 4

Numerous primary granules increase risk for DIC

Question 5

Co-expression of CD5 and CD20 suggests what?

Answer 5

Chronic lymphocytic leukemia (CLL)

Question 6

Involvement of lymph nodes leading to generalised lymphadenopathy in CLL is called:

Answer 6

small lymphocytic lymphoma

Question 7

Complications of CLL:

Answer 7

Hypogammaglobulinemia
Autoimmune hemolytic anemia
Richter transformation - transformation to diffuse large B-cell lymphoma

Question 8

Positivity for tartrate-resistant acid phosphatase (TRAP) specific for:

Answer 8

Hairy cell leukemia

Question 9

Clinical features of Hairy cell leukemia

Answer 9

Splenomegaly

Dry tap on bone marrow biopsy (marrow fibrosis)

Question 10

Rx of hairy cell leukemia

Answer 10

2-CDA (cladribine)

ADA inhibitor - adenosine accumulates to toxic levels in neoplastic B cells

Question 11

Features of adult T-cell leukemia/lymphoma (ATLL)

Answer 11

Associated with HTLV-1; Japan and Caribbean

Rash, lymphadenopathy, lytic, punchded out bone lesions with hypercalcemia

Question 12

Findings in mycosis fungoides

Answer 12

Neoplastic prolif of mature CD4+ that infiltrate skin –> skin rash, plaques, nodules
- Pautrier microabscesses (aggregates of neoplastic cells in epidermis)

Question 13

What is Sezary syndrome

Answer 13

When neoplastic cells in mycosis fungoides spread to the blood - sezary cells (cerebriform nuclei lymphocytes on smear)