Cite this page: Roychowdhury M. Frozen section-parathyroid. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/parathyroidfrozen.html. Accessed November 29th, 2024.
Definition / general
- Click here for the frozen section procedure topic
- Communication with surgeon important
- Weigh, measure and freeze largest gland
- Algorithm: presumed adenoma if rim of normal tissue, diffuse chief cell growth, no fat, bizarre nuclei; if these criteria not met, examine at least one more gland
- Oil Red O fat stain may be helpful if little fat in suspect gland and abundant fat in normal appearing gland (Am J Surg Pathol 1981;5:381, Hum Pathol 1985;16:1255)
- Density gradient measurements: denser tissue sinks in 25% mannitol solution, implies more parenchymal cells / abnormal glands
- Parathyroid tissue usually lacks birefringent calcium oxalate crystals detectable by polarized light microscopy that are present in thyroid tissue (Am J Surg Pathol 2002;26:813)
- Fewer thyroid frozen sections are now performed (Virchows Arch 2008;453:433)
Cytology description
- In touch preparations, parathyroid tissue appears as clusters of cells vs. discohesive lymphocytes and histiocytes in lymph nodes mistaken as parathyroid gland (Am J Surg Pathol 2000;24:158)
- Parathyroid: moderately cellular, small uniform cells in isolation / small groups with round / oval nuclei, salt and pepper chromatin, occasional naked nuclei, delicate vacuoles in cytoplasm and in background (Arch Pathol Lab Med 2003;127:64)
- Cytology plus frozen section is more accurate than either alone (Am J Clin Pathol 2002;118:895)
- Rapid intraoperative parathyroid hormone assay of needle aspirates is an accurate method of distinguishing parathyroid from nonparathyroid tissues during FNA as well as parathyroidectomy (Am J Otolaryngol 2011;32:574, World J Surg 2010;34:538)
Differential diagnosis
- Coexisting parathyroid and nodular thyroid disease
- Intrathyroidal parathyroid glands with conspicuous follicle formations or abundant oncocytic cells mimics thyroid tissue
- Solitary thyroid nodules with fatty stroma: see Am J Surg Pathol 1998;22:538
- Thyroid tissue with parathyroid pattern: see Mod Pathol 2000;13:210