MALToma


Expand All | Collapse All

  • Clinical

    • site: mucosa, predominantly GI
    • 7-8% of B lymphoma
    • median age 61
    • associations: chronic inflammation, autoimmune disease, H pylori, Hashimoto
    • antibiotics for H pylori associated MALToma
    • t(11;18) is resistant to H pylori therapy

  • Morphology

    • node: tumor surround follicle (marginal zone) with infiltration
    • cytology: resembles centrocyte (pale) or small lymphocyte like
    • can have plasmacytic differentiation
    • scattered large centroblast-like cells

  • Ddx

    • reactive: can have monoclonal B cell proliferation but lacks infiltration
    • DLBCL: has sheets of transformed cells (ugly blast-like cells)

  • Stains

    • positive: CD20, IgM, marginal zone antigens (CD21, CD35)
    • negative: CD5, CD10, CD23

  • Molecular

    • t(11;18) in pulmonary and gastric
    • t(14;18) in ocular, salivary glands
    • t(3;14) in thyroid, ocular, skin
    • t(1;14)
    		•