Lymphocytic/Hashimotos Thyroiditis, TBSRTC category II.
- adequate cellular smear for evaluation
- few follicles with hurthle/oncocytic cell changes (abundant granular dense eosinophilic cytoplasm and well defined cell border)
- cells shows marked nuclear enlargement and hyperchromasia, some with smudgy nuclear atypia.
- Evaluate the location of nucleus, it is not eccentric in above case.
- Evaluate the chromatin pattern, it not neuroendocrine type in above case
- Few cells show nucleoli
- thin colloid and blood in background
- sparse lymphocytes in background
- Diagnostic features of papillary thyroid carcinoma and medullary thyroid carcinoma are not appreciated.
Points of Pathoclinics:
- Moderate to marked atypia in follicular cells can be seen in Hashimotos thyroiditis, Hurthle cell neoplasm, follicular neoplasm, Long standing goiter, medullary thyroid carcinoma and anaplastic carcinoma of thyroid
- Presence of lymphocytic cells rule out Hurthle cell neoplasm. If the lesion is of pure population of hurthle cells, than the TBSRTC category IV is appropriate.
- Elevated level of anti-thyroid peroxidase and anti-thyroglobulin antibodies support the cytology diagnosis.
- Medullary thyroid carcinoma is close differentials, especially oncocytic variant. Presence of high cellularity, loose aggregates as well as single plasmacytoid or spindle cells, frequent bi-nucleated cells, salt pepper chromatin, eccentric location of nucleus and amyloid favors medullary thyroid carcinoma.
- Carefully look for nuclear inclusions and grooves to rule out oncocytic variant of papillary thyroid carcinoma.
- Number of lymphocytes has no co-relation with clinical, biochemical, radionuclide and ultrasonographic parameters.
- IgG4 positive plasma cells in Hashimotos thyroiditis are significantly associated with presence of lobulation, oncocytic metaplasia and certain type of fibrosis, fibrosis spread outside the gland, lymphocytes/plasma cells epithelial penetration, the predominance of micro follicles and follicular atrophy. Hashimotos thyroiditis with IgG4-positive plasma cells is histopathologically distinct entity. Epithelial degeneration is more common in IgG4 positive plasma cell infiltrating Hashimotos thyroiditis.
Bhatia A, Rajwanshi A, Dash RJ, Mittal BR, Saxena AK. Lymphocytic thyroiditis–is cytological grading significant? A correlation of grades with clinical, biochemical, ultrasonographic and radionuclide parameters. Cytojournal. 2007 Apr 30;4:10. doi: 10.1186/1742-6413-4-10. PMID: 17470291; PMCID: PMC1877811.CopyDownload .nbibFormat
Lintusaari J, Vesaniemi E, Kalfert D, Ilvesaro J, Ludvíková M, Kholová I. IgG4-positive plasma cells in Hashimoto thyroiditis: IgG4-related disease or inflammation-related IgG4-positivity? APMIS. 2020 Sep;128(9):531-538. doi: 10.1111/apm.13067. Epub 2020 Jul 6. PMID: 32578252.