6.6 Lymphoma

Question 1

What is a lymphoma?

Answer 1

Neoplastic proliferation of lymphoid cells that forms a mass

Can be in or out of a node

Question 2

What are the 2 major division of lymphoma?

Answer 2

Non-Hodgkin (more common) and Hodgkin

Question 3

What are the divisions of Non-Hodgkin lymphoma?

Answer 3

Based on cell size:
Small B cells: follicular, mantle cell, marginal zone, small lymphocytic lymphoma
Intermediate B cells: Burkitt lymphoma
Large B cells: diffuse large B cell lmphoma

Question 4

What is Follicular Lymphoma?

Answer 4

neoplastic proliferation of small B cells (CD20+) that form follicle-like nodules

Question 5

When does follicular lymphoma present and how?

Answer 5

Late adulthood, with painless LAD

Question 6

Patient in late adulthood presents with painless LAD and is found to have t(14;18), what is a likely Dx?

Answer 6

Follicular Lymphoma

Question 7

What drives the development of follicular lymphoma?

Answer 7

t(14;18) that moves BCL2 to locus of heavy chain Ig on chromosome 14
BCL2 stabilizes Cyt C in the mitochondria preventing apoptosis

Question 8

Follicular lymphoma treatment

Answer 8

Reserved for symptomatic patients

Low dose chemo or rtuximab (anti-CD20 Ab)

Question 9

Potential complication of follicular lymphoma

Answer 9

Progression to diffuse large B cell lymphoma presenting as an enlarging lymph node

Question 10

Rituximab

Answer 10

Anti-CD20 Ab

Question 11

What is the function of BCL2? Relation to follicular lymphoma?

Answer 11

Stabilizes mitochondrial membrane and prevents apoptosis
B cells in the follicles of nodes should undergo apoptosis regularly and should have low expression of BCL2
Follicular Lymphoma has increased production of BCL2 preventing apoptosis in the nodes

Question 12

How is follicular lymphoma differentiated from reactive follicular hyperplasia?

Answer 12

1) Disruption of normal node architecture
2) Lack of tingible body macrophages (sign of no apoptosis when not present)
3) BCL2 expression in follicle
4) Monoclonality

Question 13

How can monoclonality of B cells be gauged?

Answer 13

Look at the kappa:lambda light chain ratio
Normal: 3:1
Abnormal and sign of monoclonality: 20:1 or greater

Question 14

Patient in late adulthood presents with painless LAD and found to have B cell expansion in region immediately adjacent to the follicle. Dx?

Answer 14

Mantle Cell Lymphoma

Question 15

Mantle Cell Lymphoma

Answer 15

Neoplastic Small B cells (CD20+) expands the mantle zone

Presents in late adulthood with painless LAD

Question 16

What drives Mantle Cell Lymphoma?

Answer 16

t(11;14)
Cyclin D1 on 11 to Ig heavy chain on 14
Cyclin D1 promotes G1/S transition in the cell cycle, facilitating neoplastic proliferation

Question 17

What disease is assoc. c t(11;14) and what is the molecule overexpressed?

Answer 17

Mantle Cell Lymphoma

Cyclin D1

Question 18

Marginal cell lymphoma

Answer 18

Small B cells expanding the margin of the lymph node
Margins tend to only exist during chronic inflammatory states, so this is assoc. c them: Hashimoto thyroiditis, Sjogren, H pylori
MALToma a subtype involving mucosal sites

Question 19

Patient with gastritis from H pylori found to have a gastric MALToma, what is the expected outcome for this?

Answer 19

With resolution of H pylori infection it is expected to regress

Question 20

Young patient found to have an extranodal growing mass on the mandible. Histology shows a starry sky appearance. What is the genetic mutation driving this?

Answer 20

Burkitt Lymphoma of the jaw

t(8;14) most commonly overexpressing c-myc promoting cell growth

Question 21

What are the two forms of Burkitt Lymphoma?

Answer 21

African: jaw most commonly
Sporadic: abdomen

Question 22

What age group gets Burkitt Lymphoma?

Answer 22

Kids and young adults

Question 23

Diffuse large B cell lymphoma

Answer 23

Proliferation of large B cells that grow diffusely in sheets
Most common form of NHL
Aggressive because non-differentiated cells
Arises sporadically or from transformation of low-grade lymphoma (follicular)
Presents in late adulthood as an enlarging lymph node or an extranodal mass