Thyroid gland
Other malignancies
Lymphoma (general)

Author: Sheren Younes, M.D. (see Authors page)

Revised: 12 October 2015, last major update September 2015

Copyright: (c) 2003-2015, PathologyOutlines.com, Inc.

PubMed Search: Lymphoma [title] thyroid

Definition / General
  • Comprises 2.5% of extranodal lymphoma and 4-5% of thyroid malignancies
  • Usually arise on top of Hashimoto thyroiditis or lymphocytic thyroiditis
  • Most are diffuse large B cell lymphoma, marginal zone B cell / MALT lymphoma or mixtures of these two
    • Rarely follicular cell lymphoma
  • Hong Kong / Chinese cases are only rarely EBV+ (Am J Clin Pathol 1999;112:263)
Epidemiology
  • 75% women, usually adults or elderly (Am J Surg Pathol 2000;24:623)
  • Clinical Features
  • Rapidly growing neck mass
  • Compression symptoms including dysphagia and hoarseness
  • Can present with diffuse thyroid enlargement
  • May be accidentally discovered
  • Hypothyroid manifestations may develop
  • Cold nodule
  • Virtually all primary thyroid lymphomas are MALT-type arising after 20 - 30 years of lymphocytic thyroiditis in older patients (mean age 64 years)
  • Sequence similarity in clonal IgH bands suggests lymphoma may arise from thyroiditis (J Clin Pathol 2008;61:438)
  • Secondary involvement seen in 20% dying of generalized lymphoma, although usually does not produce clinical hypothyroidism
  • Regional lymph node enlargement can be seen
  • Prognostic Factors
  • Overall 5 year survival is 80%
  • Poor prognostic factors: diffuse B cell lymphoma subtype, perithyroidal soft tissue invasion, stage 2E or higher
  • Good prognostic factors: marginal zone lymphoma subtype or stage IE
  • Case Reports
  • 32 year old man with primary T cell lymphoma of thyroid (Med Oncol 2008;25:462)
  • 48 year old woman with primary thyroid lymphoma (Diagn Cytopathol 2012;40:444)
  • 54 year old man with primary mediastinal large B cell lymphoma (Int J Clin Exp Pathol 2015;8:5944)
  • 62 year old woman with neck mass suspicious for goiter (University of Virginia - Case 96-3)
  • 65 year old woman with thyroid MALT lymphoma (Ann Thorac Surg 2015;100:700)
  • 70 year old man with diffuse large B cell lymphoma of thyroid (Cytojournal 2006;3:23)
  • Treatment
  • Often curable by radiation or chemotherapy (particularly MALT), in contrast to anaplastic carcinoma
  • Surgery is rare (Eur J Surg Oncol 2008;34:576)
  • Gross Description
  • Variable sized, rubbery-soft mass
  • White cut surface with fish-flesh appearance
  • Necrosis could be found
  • Gross Images
    Diffuse large cell lymphoma:
    Missing Image

    Fish-flesh cut surface (AFIP)

    Missing Image

    Asymmetric enlargement of gland

    Missing Image

    Necrotic center surrounded by tan fleshy tissue

    Micro Description
    • Varies by histologic type
    • Diffuse large B cell ymphoma:
      • Diffuse infiltrate destroying thyroid follicles
      • Large cells with moderate amphophilic cytoplasm, vesicular nuclei, prominent nucleoli
      • Bizarre cells may be seen
    • MALT lymphoma:
      • Infiltration of thyroid epithelium creates lymphoepithelial lesions (lymphocytes "stuff" glandular lumina, Arch Pathol Lab Med 2007;131:1673)
      • May have background lymphocytic thyroiditis
    Micro Images
    Missing Image

    Large pleomorphic cells

    Missing Image

    Large cell type, reticulin stain
    c/o Dr. Mark R. Wick



    AFIP Images - Diffuse large B cell lymphoma:

    Missing Image

    Tumor cells

    Missing Image

    Follicle in lower right

    Missing Image

    Fibrous bands

    Missing Image

    Tumor cells are CD45 (LCA)+

    Missing Image

    Keratin, thyroglobulin



    Follicular lymphoma:

    Missing Image

    Follicular lymphoma, AFIP



    MALT lymphoma:

    Missing Image

    Centrocyte-like cells

    Missing Image

    AE1/AE3, CAM 5.2



    Cytology Description
  • Monotonous population of large atypical lymphoid cells (scant cytoplasm, finely granular chromatin, prominent nucleoli), lymphoglandular bodies present (cytoplasmic fragmentation), karyorrhexis (Cytojournal 2005;2:21
  • MALT features: see Acta Cytol 2015;59:26
  • May be misdiagnosed as lymphocytic thyroiditis
  • Cytology Images
    Diffuse large B cell lymphoma:

    Missing Image

    Large and irregular lymphoid cells

    Missing Image

    Large cell type, c/o Dr. Mark R. Wick

    Missing Image

    Misdiagnosed as anaplastic carcinoma

    Missing Image

    High grade lymphoma

    Missing Image

    CD45/LCA+, CD20+, keratin-



    Other:

    Missing Image

    Intermediate grade lymphoma

    Missing Image

    MALT lymphoma



    Positive Stains
  • CD20 and keratin highlight lymphoepithelial lesions
  • Thyroglobulin stains entrapped follicular epithelium
  • Also CD45
  • Molecular / Cytogenetics Description
  • t(11;18) is not present in thyroid MALT lymphomas (Mod Pathol 2006;19:1578)
  • Differential Diagnosis
    Additional References