Neoplasms of Mature B cells

Question 1

Burkitt Lymphoma

Answer 1

Origin: germinal center B cells
Genotype: transloction involving c-myc and Ig loci; usually t(8;14); subset EBV associated
Adolescents or young adults with extanodal masses; uncommonly present as leukemia; aggressive

Question 2

Diffuse Large B cell lymphoma

Answer 2

Origin: germinal center or post germinal center B cell
Diverse chromosomal rearrangements most often: BCL6, BCL2, c-MYC
All ages but most common in adults often appears as rapidly growing mass; 30% extranodal; aggressive

Question 3

Extranodal marginal zone lymphoma

Answer 3

Origin: Memory B cells
t(11;18), t(1;14) and t(14, 18) creating Malt1-IAP2, BCL10;IgH and MALT1-IgH fusion genes
Arises at extranodal sites in adults with chronic inflammatory diseases may remain localized; indolent

Question 4

Follicular lymphoma

Answer 4

Origin: germinal center B cell
t(14;18) creating BCL2-IgH fusion gene
older adults with generalized lymphadenopathy and marrow involvement; indolent

Question 5

Hairy cell leukemia

Answer 5

Memory B cell
no specific chromosomal abnormality
lder males with pancytopenia and splenomegally; indolent

Question 6

Mantle cell lymphoma

Answer 6

Naive B cells
t(11;14), creating Cyclin D1-IgH fusion gene
older males with disseminated disease; moderately aggressive

Question 7

Multiple myeloma/ solitary plasmactoma

Answer 7

Post-germinal center bone marrow homing plasma cell
diverse rearrangements involing IgH; 13 q deletions
Myeloma: older adults with lytic bone lesions, pathologic fractures, hypercalcemia and renal failure; moderately aggressive
Plamacytoma: isolated plasma cell masses in bone or soft tissue; indolent

Question 8

small lymphoctyic lymphoma/ chronic lymphocytic leukemia

Answer 8

Naive B cell or memory B cell
Trisomy 12, deletions of 11 q, 13q and 17 p
older adults with bone marrow, lymphnode spleen and liver disease, autoimmune hemolysis and thrombocytopenia in a minority; indolent