Non Hodgkin Lymphomas: Low Grade MCQs

Greater than 85% of follicular lymphomas have a characteristic (14;18) translocation that fuses the BCL2 gene on chromosome 18 to the IgH locus on chromosome 14. This chromosomal rearrangement results in the inappropriate 'overexpression' of BCL2 protein, which you will recall is an inhibitor of apoptosis that contributes to cell survival. Immunophenotype. These tumors express B cell markers such as CD20 and the germinal center B cell markers CD10 and BCL6; of note, BCL6 is a transcription factor that is required for the generation of germinal center B cells. Reference : Robbins, 10 th edition, page number - 468

Two thirds of hodgkin’s and non hodgkin’s lymphoma presents with nontender nodal enlargement. Two thirds of non hodgkin’s lymphoma are at extranodal sites which are Skin, stomach and brain. Reference:- Robbins, 7 th edition page number - 668

At least one quarter of non-Hodgkin’s lymphomas (NHL) arise from tissue other than lymph nodes and even from sites which normally contain no lymphoid tissue. These forms are referred to as primary extranodal lymphomas. Gastrointestinal localizations, CNS, skin (Mycosis fungoidosis), thyroid, testis. Primary nodal NHL have presentation in lymph node, Waldeyer’s ring, spleen or bone marrow Reference: Robbins & Cotran Pathologic Basis of Diseases 10 th edition, chapter 13, pg 602

Extranodal marginal zone lymphoma is an example of a cancer that arises within and is sustained by chronic inflammation. It tends to develop within tissues that are involved by chronic inflammation triggered by autoimmune disorders (such as the salivary gland in Sjogren syndrome and the thyroid gland in Hashimoto thyroiditis) or that are the sites of chronic infection (such as H. pylori gastritis). In the case of H. pylori–associated gastric marginal zone lymphoma, eradication of H. pylori with antibiotic therapy often leads to regression of the tumor cells, which depend on inflammatory cytokines secreted by H. pylori–specific T cells for their growth and survival. Reference : Robbins, 10 th edition, page number - 469

Hairy cell leukemia Hairy cell leukemia is a clonal B cell proliferation of smallto medium-sized lymphocytes that display abundant cytoplasm and hair-like protrusions of the cell membrane. The disease involves primarily the monocyte/macrophage system of the bone marrow, spleen, and liver. Hairy cell leukemia is rare and affects mainly middle-aged to elderly persons, with a markedly increased male-to-female ratio of 5:1. Unlike the other choices, hairy cell leukemia expresses tartrate-resistant acid phosphatase Reference: Robbins & Cotran Pathologic Basis of Diseases 10 th edition Chapter 13, pg 603 - 605

WHO 2016 Hematolymphoid textbook. Mantle Zone Lymphoma Positive stains - CD5, CD19 (strong), CD20 (strong), cyclin D1/BCL1 (variable nuclear staining since cells are at different stages of cell cycle) also CD22, CD43, CD79a, FMC7, surface IgM or IgD, kappa or lambda, BCL2 SOX 11 positive in cyclin D1 negative mantle lymphoma. Negative stains - CD23, usually CD10; also BCL6, CD11c, TdT, T cell antigens Reference: Robbins & Cotran Pathologic Basis of Diseases 10 th edition, chapter 13, pg 598

Mantle cell lymphoma is composed of cells resembling the naive B cells found in the mantle zones of normal lymphoid follicles. It constitutes approximately 6% of all NHLs and occurs mainly in men older than 50 years of age. Almost all tumors have an (11;14) translocation that fuses the cyclin D1 gene to the IgH locus. The tumor cells express surface IgM and IgD, the B cell antigen CD20, and CD5, and they contain high levels of cyclin D1 protein. Another marker, CD23, is a low affinity receptor for ige. It is located at the surface of B cells and binds ige/antigen complexes to be presented to specific CD4+ cells. Thus, CD23 enhances the antibody response, promotes the production of ige in its soluble form and inhibits the production of membrane ige Reference : Robbins, 10 th edition, page number - 469