*6.4.2 Highlights in recent WHO classification*

	- 1.unmutated/minimally mutated immunoglobulin heavy chain gene (IGHV) and mostly SOX11 positive
	- 2.mutated IGHV and mostly SOX11 negative (indolent leukemic non-nodal MCL with PB), bone marrow (BM), (splenic involvement, may become

**57**

*B-Cell Lymphomas*

MCL.

**Figure 4.**

cal risk.

*6.4.3 Treatment and prognosis*

*Mantle cell lymphoma showing cyclin D1 positivity.*

**6.5 Marginal zone lymphomas**

extranodal marginal zone lymphomas [1, 25].

*6.5.1 Nodal marginal zone B-cell lymphoma*

*DOI: http://dx.doi.org/10.5772/intechopen.87370*

more aggressive).Mutations of potential clinical importance, such as TP53,

• CCND2 (Cyclin D2) rearrangements in approximately half of cyclin D1 negative

In situ mantle cell neoplasia—New name for in situ MCL, reflecting low clini-

MCL is usually not curable with conventional chemotherapy, and most patients succumb to organ dysfunction caused by tumor infiltration. The prognosis is poor with median survival of only 3–4 years. The blastoid variant is associated with even shorter survivals. Hematopoietic stem cell transplantation and proteasome inhibi-

Marginal zone lymphoma (MZL) is a group of B-cell tumors that arise from lymph nodes, spleen, or extranodal tissues. In most cases, there is evidence of somatic hypermutation of memory B-cell origin. The disease begins as a polyclonal immune reaction. With time, however, tumors may acquire additional mutations that render their growth and survival antigen-independent, such as the (11; 18), (14; 18), or (1; 14) chromosomal translocations, which are relatively specific for

Nodal marginal zone B-cell lymphomas are uncommon lymphomas in which the tumor cells resemble the cytology of those in splenic and extranodal marginal zone B-cell lymphomas of MALT, but there is no evidence for splenic or extranodal disease. Clinically, these lymphomas appear more extensive at presentation than

NOTCH 1/2, recognized in a small proportion of cases.

tors are newer therapeutic approaches that show some promise [1, 25].

*Normal and Malignant B-Cell*

*6.3.4 Duodenal-type FL*

with 1p36 deletion.

*6.3.5 Treatment and prognosis*

**6.4 Mantle cell lymphoma**

localized mass, often inguinal.

• Localized process with low risk for dissemination. Predominantly diffuse FL

• Accounts for some cases of diffuse FL lacks BCL2 rearrangement; presents as a

Histological grade correlates with prognosis with grade 1–2 follicular lymphoma cases being indolent and usually not curable by aggressive therapy; and needs to palliate patients with low-dose chemotherapy or immunotherapy (e.g., anti-CD20 antibody). Median survival is 7–9 years. Histologic transformation occurs in 30–50% of follicular lymphomas, most commonly to diffuse large B-cell lymphoma [1, 25].

Mantle cell lymphoma (MCL) is an uncommon lymphoid neoplasm. It usually presents in the fifth to sixth decades of life and shows a male predominance. Virtually all mantle cell lymphomas have an (11; 14) translocation involving the IgH locus on chromosome 14 and the cyclin D1 locus on chromosome 11 that leads to overexpression of cyclin D1. The most common presentation is painless lymphadenopathy. Symptoms related to the involvement of the spleen (present in ~50% of cases) and extranodal sites are also common. In GIT present as lymphomatous

MCL consists of a homogeneous population of small lymphocytes with irregular to occasionally deeply clefted (cleaved) nuclear contours. In most cases the nuclear chromatin is condensed, nucleoli are inconspicuous, and the cytoplasm is scant. It usually has a diffuse growth pattern or surrounds reactive germinal centers in a mantle zone pattern. Extension of the lymphoma into the capsule and perinodal fat is common Occasionally, tumors composed of intermediate-sized cells with more open chromatin and a brisk mitotic rate are observed; immunophenotyping is

Mantle cell lymphomas express high levels of cyclin D1. Most tumors are also

• Two MCL subtypes recognized with different clinicopathological manifesta-

1.unmutated/minimally mutated immunoglobulin heavy chain gene (IGHV)

2.mutated IGHV and mostly SOX11 negative (indolent leukemic non-nodal MCL with PB), bone marrow (BM), (splenic involvement, may become

tions and molecular pathogenetic pathways [24, 52–54]

express CD19, CD20. It is usually CD5+, SOX11 +, FMC7+ (Flinders Medical Centre), BCL1+ and CD23−, CD10−, CD200−, LEF1−, which help to distinguish it from CLL/SLL. The IgH genes lack somatic hypermutation, supporting an origin

polyposis of the lower gastrointestinal tract [1, 25, 52].

necessary to distinguish these "blastoid" variants.

*6.4.1 Morphology and immunophenotype*

from a naive B cell [25] (**Figure 4**).

*6.4.2 Highlights in recent WHO classification*

and mostly SOX11 positive

**56**

**Figure 4.** *Mantle cell lymphoma showing cyclin D1 positivity.*

more aggressive).Mutations of potential clinical importance, such as TP53, NOTCH 1/2, recognized in a small proportion of cases.

• CCND2 (Cyclin D2) rearrangements in approximately half of cyclin D1 negative MCL.

In situ mantle cell neoplasia—New name for in situ MCL, reflecting low clinical risk.
