Topic 27-30: lymphoid neoplasia part 2

Question 1

follicular lymphoma is what? how common? what genetic defects?

Answer 1

B cell neoplasm like CLL/SLL that is incurable and found in the germinal centers.

it causes about 40% of adult NHL

neoplastic cells express BCL2 and 85% of tumors have a t(14,18)BCL2/IgH

Question 2

What is the morphology of lymph nodes with FL? markers?

Answer 2

nodular proliferation with follicular hyperplasia

Pan B-cell markers: CD19, 20, 10, BCL6 (a transcription factor related to follicular cell formation)

Question 3

mantle cell lymphoma is what, how common, and which mutations?

Answer 3

tumor cells found in the mantle zone of lymph follicles

not common, only 4% of NHL

t(11;14)- fuses cyclin D1 from chromosome 11 to heavy chain gene on chromosome 14 → increased levels of cyclin D1 (cell cycle regulator)

Question 4

mantle cell lymphoma cells have which markers? how do you distinguish from CLL/SLL?

Answer 4

these cells have IgM, IgD, CD 19and 20

the difference btw CLL and MCL is that MCL has the cyclin D1 protein mutation and no proliferating centers (as seen in SLL,CLL)

Question 5

what is the morphology of MCL?

Answer 5

Nodular pattern in lymph nodes

bm Involved and peripheral blood involvement (20% of the time)

Question 6

MALT lymphoma is what and arises in which situations?

Answer 6

low grade mature B cell tumor that in seen in MALT tissue

typically occurs in setting of autimmune or chronic infections such as H.pylori

Question 7

what is the genetic abnormality associated with MALT lymphoma?

Answer 7

t(11,18) MALT/IAP2

from age 11 to 18, walt and I ate pizza

Question 8

Diffuse large B-cell lymphoma is from which cells and how common?

Answer 8

Lymphoma with no follicular pattern. The nucleus of the neoplastic B cells is 3-4 times larger than the normal and has several forms. 2 cell types:
-Centroblast: large cells that are seen in reactive GC. good prognosis

-Immunoblasts: a type of antigen-activated lymphocyte that is normally found in the paracortex of lymph nodes. bad prognosis

The most important type of lymphoma in adults, accounts for 50% of adult NHL

Question 9

DLBCL is associated with which mutations?

Answer 9

• 30% have BCL6 rearrangement (point mutations at promoter that results in inc bcl6 proteins which upregulate transcription)
• 30% have t(14,18) BCL2 overexpression
• 30% have lost the function of the histone acetyl transferase (thus they can’t activate genes)

Question 10

Burkitt lymphoma is what and associated with which mutations?

Answer 10

an EBV assocaiated B cell neoplasm that has a t(8,14)MYC/IgH (or light chain genes such as 2 or 22) which causes an overproduction of Myc proteins that drive proliferation

Question 11

what morphology do you see with Burkitt lymphoma?

Answer 11

numerous benign tissue macrophages are present, containing ingested nuclear debris. They are often surrounded by clear space, creating a “starry sky” pattern.

-diffuse involvement of lymph nodes

Question 12

what are the 3 groups of burkitt lymphoma? how common is it generally?

Answer 12

africa - children, maxillary or mandibular, EBV

europe, north america - NOT always EBV! not oral-facial, but GI lymph nodes!

immunodef/post-transplant - EBV related

BL is 30% of childhood lymphoma

Question 13

what are the three peripheral/mature T/NK cell neoplasms?

Answer 13

• Cutaneous T cell lymphoma (sezary syndrome and mycosis fungoides)
• Adult T cell lymphoma/leukemia
• peripheral T cell lymphoma

Question 14

explain the 2 Cutaneous T cell lymphoma

Answer 14

mycosis fungoides - starts as a rash that progesses to a palque and then tumor phase. can have nodal and visceral dissemination

sezary syndrome - exfoliative erthroderma with tumor cells in the peripheral blood (sezary cells)

Question 15

T cell leukemia and lymphoma are caused by what? what is the morphology?

Answer 15

caused by Human T-cell leukemia virus type-1 (retrovirus)

• causes transverse myelitis (demyelination of the spinal cord)
• lymphoid malignancy, skin lesions,

very low survival, 8 months median, poor response to therapy

Question 16

peripheral t cell lymphoma is what?

Answer 16

catch all for unclassifiable T cell tumors, makes up about 15% of tumors

Question 17

Hodgkins lymphoma is characterized by which cells?

Answer 17

Reed-sternberg cells -Have multinucleated giant cells, owl-eye clear zone inclusion in nuclei.

Question 18

What are the subtypes of HL?

Answer 18

• Nodular sclerosis
• Mixed cellularity
• Lymphocyte rich
• lymphocyte depleted

Question 19

Reed-sternberg cells are typically seen in which HL subtypes?

Answer 19

Mixed cellularity

Question 20

Which subtype of HL is the most common? What is the common cell, node location and morphology?

Answer 20

Nodular sclerosis HL

• found in lower cervical, supraclavicular and mediastinal nodes
• lacunar cells - multilobulated nuclei, same immunophenotype as RS cells
• node fibrosis via collagen bands that divide nodes into nodules

Question 21

Which subtype of HL is the most common in OLDER Patients? What is the common cell, node location and morphology?

Answer 21

Mixed cellularity HL

• RS cells surrounded by general inflammatory cells (lymphocytes, eosinophils, macrophages)
• normally disseminated and seen with systemic symptoms

Question 22

lymphocyte predominance HL. What is the common cell, node location and morphology?

Answer 22

RS variant cells

-Isolated cervical or axillary node involvement, excellent prognosis

Question 23

In HL, can extranodal involvement occur?

Answer 23

yes, in all forms of HL, you can find RS cells in the liver, spleen, BM etc however it is uncommon

Question 24

70% of HL has what integrated into the RS cell DNA?

Answer 24

EBV genome

Question 25

what are the staging of HL?

Answer 25

ann arbor classification, 1-4

1. single lymph node region
2. 2+ lymph node regions on the same side of the diaphragm or extra lymph involvement
3. both sides of diaphragm lymph node involvement, organ involvement
4. disseminated

stage 1-2 = 100% survival
stage 2-3 = 50%