B-cell lymphoma

Question 1

What test can help distinguish between low-grade B-cell lymphomas and cutaneous lymphoid hyperplasia?

Answer 1

IgH clonality

Question 2

what is the definition of a primary cutaneous B-cell neoplasm?

Answer 2

They are limited to the skin after systemic workup (except for the intravascular B-cell lymphoma)

Question 3

What is the most sensitive stain for B-cells?

Answer 3

Pax-5

Question 4

What are the 4 main cutaneous b-cell lymphomas?

Answer 4

1. Primary cutaneous follicle center cell lymphoma,
2. primary cutaneous marginal zone lymphoma,
3. primary cutaneous diffuse large B-cell lymphoma, leg type.
4. Intravascular B-cell lymphoma

Question 5

What is the clinical features of primary cutaneous follicle center cell lymphoma?

Answer 5

Violaceous usually solitary papule or nodule on the Scalp/forehead (m/c) or the back (crosti’s tumor)

Question 6

What is Crosti’s lymphoma?

Answer 6

It is primary cutaneous follicle center cell lymphoma on the back

Question 7

What is the prognosis of primary cutaneous follicle center cell lymphoma?

Answer 7

Very good prognosis

Question 8

What are the histologic features of primary cutaneous follicle center cell lymphoma?

Answer 8

Irregular shaped neoplastic follicles; lacks well-defined mantle zone and tingible body macrophages

-Lacks t(14;18) IgH-Bcl-2 translocation characteristic of systemic follicular lymphoma

-BCL-6 (+) and BCL-2 -

Question 9

What is the clinical appearance of primary cutaneous marginal zone lymphoma?

Answer 9

Purple to brown nodule on the upper extremities or trunk

Question 10

Prognosis of primary cutaneous marginal zone lymphoma?

Answer 10

Very good

Question 11

What is the histology of primary cutaneous marginal zone lymphoma?

Answer 11

Nodular dermal infiltrate w/ prominant monocytoid B-cells (small lymphocytes w/ clear halo) and often numerous plasma cells (major clue), some Dutcher bodies

-BCL 6 - BCL-2 (+)

Question 12

What is the clinical presentation of the primary cutaneous diffuse large B-cell lymphoma, leg type?

Answer 12

Elderly, F>M; red to brown nodule on distal extremity (Leg is the #1 spot), but it can occur at other sites

Question 13

What work up must be done if you see primary cutaneous diffuse large B-cell lymphoma, leg type?

Answer 13

Must do systemic workup and r/o systemic disease

Question 14

What is the prognosis of primary cutaneous diffuse large B-cell lymphoma, leg type?

Answer 14

Less favorable than others, ~50% 5-year survival

Question 15

What is the histologic features of primary cutaneous diffuse large B-cell lymphoma, leg type?

Answer 15

Dense sheets of large round, markedly atypical lymphocytes w/ mitoses and apoptotic debris in dermis and possible subcutis; grenz zone

-Bcl-2 +; BCL-6+ (most cases), and MUM-1+

Question 16

What is the clinical appearance of intravascular B-cell lymphoma?

Answer 16

Purple patches and plaques; trunk/thighs; usually systemic involvement including CNS (progresses to neuro deficits), but it can also be limited to just the skin

Question 17

What is the histologic characteristics of intravascular B-cell lymphoma?

Answer 17

Large atypical CD20+ B-lymphocytes within vessels

Question 18

Which cutaneous B-cell lymphoma is BCL-6 + but BCL-2 -

Answer 18

Primary cutaneous follicle center cell lymphoma

Question 19

Which cutaneous b-cell lymphoma is BCL-6 - and BCL-2 +?

Answer 19

Primary cutaneous marginal zone lymphoma

Question 20

Which cutaneous B-cell lymphoma is Bcl-2 +, BCL-6 + and MUM-1 +

Answer 20

Primary cutaneous diffuse large B-cell lymphoma, leg type