*6.8.2 Highlights in recent WHO classification*


#### *6.8.3 Treatment and prognosis*

DLBCLs are aggressive tumors that are rapidly fatal without treatment. With intensive combination chemotherapy, 60–80% of patients achieve a complete remission, and 40–50% are cured. Adjuvant therapy with antiCD20 antibody improves both the initial response and the overall outcome. DLBCLs with MYC translocations have a worse prognosis than those without and may be better treated with chemotherapy regimens for Burkitt lymphoma [1, 25].

#### **6.9 Hairy cell leukemia (HCL)**

Hairy cell leukemia (HCL) is a rare but distinctive B-cell neoplasm constitutes about 2% of all leukemia. It is predominantly a disease of middle-aged white males, with a median age of 55 and a male-to-female ratio of 5:1. Hairy cell leukemia are associated in more than 90% of cases with activating point mutations in the serine/ threonine kinase BRAF (B-Raf) [66]. Patients usually presents with massive splenomegaly. Hepatomegaly is less common and lymphadenopathy is rare. Pancytopenia is seen in more than half the cases [1, 25].

**63**

*B-Cell Lymphomas*

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

*6.9.1 Morphology and immunophenotype*

FMC-7 and cyclin D1 (usually weak) [1, 25].

chemotherapy. The overall prognosis is excellent [1, 25].

**6.10 Plasma cell neoplasms and related disorders**

*6.9.2 Treatment and prognosis*

On routine peripheral blood smears, the cells have round, oblong, or reniform nuclei and moderate amounts of pale blue cytoplasm with thread-like or bleb-like extensions. On bone marrow aspiration the cells cannot be aspirated and gives "dry tap", Bone marrow biopsy shows diffuse interstitial infiltrate of tumor cells enmeshed in an extracellular matrix composed of reticulin fibrils giving fried egg appearance. Spleen appears beefy red on gross appearance. Microscopy shows heav-

The classic immunophenotypic profile of HCL consists of bright monotypic surface immunoglobulin, bright coexpression of CD20, CD22 and CD11c, and expression of CD103, CD25, CD123, T-bet, Annexin A1 (ANXA1), DBA.44 (CD72),

Hairy cell leukemia follows an indolent course and is sensitive to "gentle" chemotherapeutic regimens, which produce longlasting remissions. BRAF inhibitors appear to produce excellent responses in tumors that have failed conventional

These B-cell proliferations contain neoplastic plasma cells that virtually always secrete a monoclonal Ig or Ig fragment. These plasma cell neoplasms are also termed as plasma cell dyscrasias. Multiple myeloma is associated with frequent rearrangements involving the IgH locus and various proto-oncogenes. Included among the loci that are recurrently involved in translocations with the Ig heavy-chain gene on chromosome 14q32 are the cell cycle-regulatory genes cyclin D1 on chromosome 11q13 and cyclin D3 on chromosome 6p21. Deletions of chromosome 17p that involve the TP53 tumor suppressor locus also occur and are associated with a poor outcome. Late-stage, highly aggressive forms of the disease such as plasma cell leukemia are associated with the acquisition of rearrangements involving MYC. More recent deep sequencing of myeloma genomes has identified frequent mutations involving components of the nuclear factor κ B (NF-κB) pathway, which supports B-cell survival. Based on these

studies, it is evident that myeloma is molecularly heterogeneous [1, 67]. The various spectrum of plasma cell dyscrasias are [68]:

**IgM monoclonal gammopathy of undetermined significance**

Serum monoclonal protein (non-IgM type) <30 g/dl.

Bone marrow lymphoplasmacytic infiltration <10%.

Clonal bone marrow plasma cells <10%.

Serum IgM monoclonal protein <30 g/dl.

the underlying lymphoproliferative disorder.

plasma cell proliferative disorder.

**Non-IgM monoclonal gammopathy of undetermined significance**

The absence of end-organ damage such as hypercalcemia, renal insufficiency, anemia, and bone lesions (CRAB) or amyloidosis that can be attributed to the

No evidence of anemia, constitutional symptoms, hyperviscosity, lymphadenopathy, hepatosplenomegaly, or other end-organ damage that can be attributed to

ily infiltrated splenic red pulp leading to obliteration of white pulp.

*Normal and Malignant B-Cell*

*6.8.2 Highlights in recent WHO classification*

*Diffused large cell lymphoma showing diffuse effacement by large cells.*

may affect therapy [24, 62–65].

determined. EBV+ DLBCL, NOS.

expressor lymphoma).

patients.

**Figure 8**

diagnosis.

*6.8.3 Treatment and prognosis*

**6.9 Hairy cell leukemia (HCL)**

is seen in more than half the cases [1, 25].

• The distinction of germinal center B-cell-like (GCB) vs. activated B-cell-like (ABC)/non-GC type required with the use of immunohistochemical algorithm

• Coexpression of MYC and BCL2 considered new prognostic marker (double-

• Mutational landscape better understood but the clinical impact remains to be

• This term replaces EBV+ DLBCL of the elderly because it may occur in younger

• Does not include EBV+ B-cell lymphomas that can be given a more specific

DLBCLs are aggressive tumors that are rapidly fatal without treatment. With intensive combination chemotherapy, 60–80% of patients achieve a complete remission, and 40–50% are cured. Adjuvant therapy with antiCD20 antibody improves both the initial response and the overall outcome. DLBCLs with MYC translocations have a worse prognosis than those without and may be better treated

Hairy cell leukemia (HCL) is a rare but distinctive B-cell neoplasm constitutes about 2% of all leukemia. It is predominantly a disease of middle-aged white males, with a median age of 55 and a male-to-female ratio of 5:1. Hairy cell leukemia are associated in more than 90% of cases with activating point mutations in the serine/ threonine kinase BRAF (B-Raf) [66]. Patients usually presents with massive splenomegaly. Hepatomegaly is less common and lymphadenopathy is rare. Pancytopenia

with chemotherapy regimens for Burkitt lymphoma [1, 25].

**62**
