Functional state of cells during their life and on their journey toward inactivity and death: Search for morphological evidence in thyroid fine needle aspiration smears

Dilip K DasJournal of Cytology 2018 35(3):131-138 Synthesis and storage of thyroglobulin as well as synthesis of thyroid hormones and their release into the circulation are important functions of thyroid, which were studied in fine needle aspiration (FNA) smears from thyroid lesions. Evidence of thyroglobulin synthesis was demonstrated in neoplastic and nonneoplastic follicular cells, especially in Hürthle cells, in the form of colloid inclusions. Whereas the pinocytic vesicles containing colloid at the luminal end of in nonneoplastic and neoplastic follicular cells indicated engulfment of colloid for synthesis of thyroid hormones (T3and T4), the marginal vacuoles (MVs) (fire-flare appearance) at the basal aspects of follicular cells suggested their release on way to the interfollicular capillaries. The morphological evidence of secretary activity could also be demonstrated in medullary thyroid carcinoma (MTC) in the form of azurophilic granules, marginal vacuoles, and intracytoplasmic lumina (ICL) with secretions; the secretory material, likely to be amyloid, present in MTC cells, and their release to the extracellular space was confirmed by positive immunocytochemical staining for calcitonin. It was found that nuclear grooves and related intranuclear cytoplasmic inclusions (INCIs) in papillary thyroid carcinoma (PTC) possibly represent an initial step of a degenerative process leading to formation of inactive cerebriform nuclei. Based on observation regarding f...
Source: Journal of Cytology - Category: Cytology Authors: Source Type: research