Thyroid & parathyroid
Thyroiditis
Hashimoto thyroiditis
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PubMed Search: Hashimoto thyroiditis thyroid gland
Related Topics: Fibrous (fibrosing) variant
- Autoimmune disease with goiter, elevated circulating antithyroid peroxidase and antithyroglobulin antibodies
- First described by Hakaru Hashimoto in 1912 (World J Surg 2008;32:688)
- Also called Hashimoto disease, struma lymphomatosa, lymphocytic thyroiditis
- Hashitoxicosis: features of Hashimoto thyroiditis and Graves disease
- 90 - 95% in women, usually 45 - 65 years old; clusters in families
- More common in Whites than Blacks or Japanese (Am J Clin Pathol 1994;101:698)
- Most common cause of sporadic goiter in children in iodine sufficient areas (J Pediatr Endocrinol Metab 2007;20:1199)
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Grading of thyroiditis on cytological material
- Adults present with painless, gradual thyroid failure due to autoimmune destruction, may initially have transient hyperthyroidism
- Children have variable hypothyroidism and reversion to euthyroidism so must monitor thyroid function (Clin Endocrinol (Oxf) 2009;71:451)
- No female predominance in children with Down syndrome (Horm Res 2008;70:278)
- Associated with HLA-DR5 (goitrous form), HLA-DR3 (atrophic form)
- May coexist with SLE, rheumatoid arthritis, Sjögren syndrome, pernicious anemia, type 1 diabetes, Graves disease, chronic active hepatitis, adrenal insufficiency, MALT lymphoma of gastrointestinal tract (80:1 relative risk), other B cell lymphomas
- Associated with well differentiated thyroid cancer (J Am Coll Surg 2007;204:764)
- May evolve into thyroid lymphoma (J Clin Pathol 2008;61:438)
- At thyroidectomy, cancer is common, even if not suspected preoperatively (Thyroid 2008;18:729)
- Autoantibodies include:
- Anti TSH (specific for Hashimoto and Graves disease)
- Antithyroglobulin (less sensitive but similar specificity as antithyroid peroxidase, Clin Chem Lab Med 2006;44:837)
- Antithyroid peroxidase (previously called antimicrosomal antibody, sensitive but not specific as 20% of adult women without disease have these antibodies); anti-iodine transporter (rare)
- Note: anti TSH antibodies block the TSH receptor in Hashimoto disease but stimulate the TSH receptor in Graves disease
Contributed by Ayana Suzuki, C.T.
Isoechoic nodule
- 41 year old woman with hypothyroidism and multinodular goiter (Arch Pathol Lab Med 2003;127:e253)
- 43 year old woman with coexisting affective psychosis and brain perfusion abnormalities (Clin Pract Epidemiol Ment Health 2007;3:31)
- Often no treatment needed, thyroid hormone for hypothyroidism (may remain euthyroid after 1 year when drug is withdrawn), subtotal thyroidectomy to relieve mass effect
- Rarely progresses to lymphoma
- Diffuse symmetric enlargement of thyroid gland (25 - 250 g) with intact capsule, pyramidal lobe may be prominent
- May have adhesions but thyroid gland is easily separated from other structures
- Cut surface resembles lymph nodes with tannish yellow color
- May have increased interlobular fibrosis or be fibrotic, particularly in elderly patients
- Gland may atrophy
- Occasionally gland is nodular or asymmetric
- No necrosis or calcification
Contributed by Mark R. Wick, M.D.
Various images
Large cell lymphoma
AFIP images
Symmetrical enlargement
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Atrophic gland
Nodular gland
- Extensive lymphocytic infiltrate with germinal center formation
- Lymphocytes are predominantly T cells and plasma cells (polyclonal)
- Atrophic follicles with abundant Hürthle cells / oncocytes but no / reduced colloid
- Fibrosis may be increased but does not extend beyond capsule
- May see giant cells
- Epithelium may have enlarged or overlapping nuclei with partial nuclear clearing, large squamous nests, hyperplastic follicles, ductal metaplasia (Am J Surg Pathol 2006;30:774)
- Squamous metaplasia of follicular epithelium can be confused with solid cell nests (J Clin Endocrinol Metab 2012;97:2209)
- Occasionally is nodular
- Initial lesion is focal, then oxyphilic metaplasia of follicular cells and nodularity; later little thyroid parenchyma is present
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Lymphoid follicles with germinal centers
Diffuse lymphoplasmacytic infiltration
Squamous metaplasia: p63+ cells in many follicles
Evolution of squamous metaplasia
Intense immunostaining
Lobulation of thyroid tissue by fibrotic bands
Vesicular nuclei of thyroid follicles similar to PTC nuclei
Aggregation of lyphoid follicles mimic thyroid nodule
Hashimoto thyroiditis with lymphoepithelial cyst
Nodular Hashimoto thyroiditis
Papillary microcarcinoma and Hashimoto thyroiditis
Contributed by Mark R. Wick, M.D.
Hashimoto thyroiditis
Branchial cyst-like change
With large cell lymphoma
Sclerosing variant
With marginal zone lymphoma
With sequestered thyroid nodule
AFIP images
Squamous lined cyst
Clear cell change
Clear nuclei
Circumscribed nodules
Benign follicular nodule
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Nodular gland with prominent lymphoid follicles
Atrophic thyroid follicles and prominent lymphoid follicles
Lymphoid follicle and prominent Hürthle cells
Lymphocytes, plasma cells, Hürthle cells and giant cells
Chronic inflammation and Hürthle cells
Oxyphilic degeneration of epithelium
Prominent
lymphoid
follicles and
abundant colloid
Lymphoplasmacellular inflammation, destroyed follicles with sparse colloid, prominent Hürthle cells
With residual Graves disease
CD68+ giant cells
Antimicrosomal antibody
Antithyroglobulin antibody
- Moderately cellular with aggregates of oncocytes (finely granular cytoplasm, large hyperchromatic nuclei, variable pleomorphism) and mature lymphocytes; also follicular cells, plasma cells, macrophages, neutrophils
- Can grade based on lymphocytic infiltration from 0 to 3+ (see Diagrams / Tables section above), but does not correlate with clinical parameters (Cytojournal 2007;4:10)
Contributed by Ayana Suzuki, C.T.
Lymphocytes and oncocytes
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Oncocytic cells with atypical nuclei
Sheet of follicular cells with oncocytic change mixed with benign lymphoid cells
Resembles lymphoma
Grade I: mild lymphocytic inflammatory infiltrate
Grade II: moderate lymphocytic inflammation
Grade III: marked
inflammation with
polymorphous
lymphocytes
ThinPrep versus Pap stain
- High molecular weight keratin, p63 (Hum Pathol 2003;34:764)
- May have elevated kappa / lambda ratio (Am J Clin Pathol 2006;125:42)
- Mixture of T and B cells
- Oncocytic cells have many large mitochondria, reduced numbers of other organelles
- Not monoclonal (Hum Pathol 1988;19:1444)
Thyroid: compare and contrast
Histopathology thyroid: Hashimoto thyroiditis
- Hürthle cell neoplasms
- Lithium intake: causes similar morphologic findings (Hum Pathol 1983;14:737)
- MALT lymphoma: mostly B cells, clonal, destructive lymphoepithelial lesions (Am J Clin Pathol 1998;110:327)
- Papillary carcinoma: similar nuclear features, but diffuse, compared to focal features in Hashimoto
