Thyroid Lymphoma
Susan L. Haley, MD
Key Facts
Clinical Issues
Generally associated with lymphocytic thyroiditis
Cytopathology
Hypercellular aspirate of noncohesive lymphoid cells
Lymphoglandular bodies are usually present
May see lymphoepithelial lesions or germinal centers
DLBCL: Large, round, immature lymphocytes
EMZBCL: Mix of small atypical lymphocytes
Ancillary Tests
CD20 and CD79-a confirm B-cell immunophenotype
Flow cytometry is helpful to characterize clonality
Cytogenetic and molecular features are less extensive than in other sites
Top Differential Diagnoses
Lymphocytic thyroiditis
Undifferentiated thyroid carcinoma
Melanoma
TERMINOLOGY
Abbreviations
Diffuse large B-cell lymphoma (DLBCL)
Extranodal marginal zone B-cell lymphoma (EMZBCL)
Definitions
Primary lymphoma arising in thyroid
CLINICAL ISSUES