Chapter12- PERIPHERAL B-CELL NEOPLASMS: Mantle cell lymphoma

Question 1

What is Mantle cell lymphoma?

Answer 1

• uncommon lymphoid neoplasm
• that makes up about 2.5% of NHL in the United States and 7% to 9% of NHL in Europe.
• usually presents in the fifth to sixth
• decades of life
• male predominance.

As the name implies, the tumor cells closely

resemble the normal mantle zone B cells that surround germinal centers.

Question 2

What is the morphology of Mantle cell Lymphoma?

Answer 2

Nodal tumor cells may surround reactive germinal centers to produce a nodular
appearance at low power, ordiffusely efface the node.

Typically, the proliferation consists
of a homogeneous population of small lymphocyteswith irregular to occasionally deeply clefted (cleaved) nuclear contours ( Fig. 13-20 ).

Question 3

What is the distinguishing feature of Mantle cell lymphoma from CLL/SLL?

Answer 3

Large cells resembling
centroblastsandproliferation centers are absent, distinguishing mantle cell lymphoma from
follicular lymphoma and CLL/SLL, respectively

. In most cases the nuclear chromatin is
condensed, nucleoli are inconspicuous, and the cytoplasm is scant.

Occasionally, tumors
composed of intermediate-sized cells with more open chromatin and a brisk mitotic rate are
observed; immunophenotyping is necessary to distinguish these “blastoid” variants of mantle
cell lymphoma from ALL

Question 4

What is the distinguishing feature of Mantle Cell Lymphoma from ALL

Answer 4

Occasionally, tumors
composed of intermediate-sized cells with more open chromatin and a brisk mitotic rate are
observed; immunophenotyping is necessary todistinguish these “blastoid” variants of mantle
cell lymphoma from ALL

Question 5

Answer 5

FIGURE 13-20 Mantle cell lymphoma.

• A, At low power, neoplastic lymphoid cells surround a small, atrophic germinal center, producing a mantle zone pattern of growth.
• B, Highpower view shows a homogeneous population of small lymphoid cells with somewhat irregular nuclear outlines, condensed chromatin, and scant cytoplasm. Large cells resembling prolymphocytes (seen in chronic lymphocytic leukemia) and centroblasts (seen in follicular lymphoma) are absent.

Question 6

At diagnosis of Mantle Cell Lymphoma the majority of patients have what?

Answer 6

• generalized lymphadenopathy,
• and 20% to 40% have peripheral blood involvement.

Frequent sites of extranodal involvement include the bone marrow, spleen, liver, and gut.

Occasionally, mucosal involvement of the small bowel or colon produces polyp-like lesions (lymphomatoid polyposis); of all forms of NHL, mantle cell lymphoma
is most likely to spread in this fashion.

Question 7

In Mantle Cell lymphoma, when there is mucosal involvement of the small bowel color produces polyp-like lesions called what?

Answer 7

(lymphomatoid polyposis);

of all forms of NHL, mantle cell lymphoma
is most likely to spread in this fashion.

Question 8

Among all the NHL which most likely to spread in this lymphomatoid polyposis fashion.

Answer 8

mantle cell lymphoma

Question 9

What is the Immunophenotype of Mantle cell lymphoma?

Answer 9

Mantle cell lymphomas express high levels of cyclin D1.

• *Most tumors** are also express CD19,
• *CD20**, and moderately high levels of surface Ig (usually IgM and IgD with κ or γ light chain).

It is usually CD5+ and CD23-, which helps to distinguish it from CLL/SLL.

The IgH genes lack
somatic hypermutation, supporting an origin from anaive B cell.

Question 10

What immunophenotype can help to distinguish Mantle cell lymphoma from CLL/SLL?

Answer 10

It is usually CD5+ and CD23-, which helps to distinguish it from CLL/SLL.

Question 11

What is the supporting evidence that Mantle Cell lymphoma is an origin from a naive B cell?

Answer 11

IgH genes lack
somatic hypermutation

Question 12

What is the molecular pathogenesis of Mantle cell lymphoma?

Answer 12

Cyclin D1 overexpression is caused by an (11;14) translocation involving the IgH locus on
chromosome 14 and the cyclin D1locus on chromosome11.

This translocation is detected in

• *about 70% of cases by standard karyotyping and in virtually all tumors by fluorescence in situ
  hybridization. **

The resulting up-regulation of cyclin D1 promotes G1- to S-phase progression during the cell cycle, as was described in Chapter 7

Question 13

What are the clinical features of Mantle cell lymphoma?

Answer 13

The most common presentation is painless lymphadenopathy.

Symptoms related to involvement
of the spleen (present in ∼50% of cases) and the gut are also common.

Question 14

What is the prognosis of Mantle cell lymphoma?

Answer 14

The prognosis is poor;
the median survival is only 3 to 4 years.

Question 15

What is the treatment for Mantle cell lymphoma?

Answer 15

This lymphoma is not curable with conventional
chemotherapy, and most patients eventually succumb to organ dysfunction caused by tumor
infiltration

.

Question 16

Which are associated to Mantle Cell Lymphoma with even shorter survivals?

Answer 16

The blastoid variant and a “proliferative” expression profiling signature are associated with even shorter survivals. [26]

Question 17

Wha are the new therapeutic approaches showing some promise in Mantle Cell Lymphoma?

Answer 17

Bone marrow transplantation and proteasome
inhibitors.