Background: Thyroid disorders are considered a major health problem all over the world and in our society in Egypt. All over time there were a number of classifications and updates about thyroid pathology. The objective of the present study is to apply the latest World Health Organization (WHO) update about thyroid neoplasm. Overall, the new classification is helpful in the new knowledge of pathology, clinical behavior, and tumor genetics that help in patient management to avoid overdiagnosis and overtreatment of patients with indolent thyroid tumors that cause no harm to patients.
Aim of the work: Microscopic evaluation of all thyroidectomy specimens enrolled at South Egypt Cancer Institute from the period of Jan 2008 to Dec 2018 in the light of new WHO classification with emphasis on criteria of the borderline tumor in the form of evaluation of the pattern either follicular or papillary pattern, assessment of presence or absence of papillary nuclear features and assessment of capsular or vascular invasion.
Results: Out of 590 thyroidectomy specimens, 462 (78.3%) were females and 128 (21.7%) were males. The studied cases included 315 hyperplastic cases (53.4%), 53 inflammatory cases (9%), and 222 (37.6%) neoplastic cases. 11 cases fulfilled the borderline criteria (1.9%) 9 cases of noninvasive follicular tumor with papillary like nuclear features (NIFTP) & only 2 cases of well differentiated follicular tumor of uncertain malignant potential WDTUMP.
Conclusion: Thyroid lesions show female predominance with a female to male ratio of 3.72 to 1. The peak incidence for thyroid lesions is commonly seen in fourth decade. Non-neoplastic cases outnumber neoplastic cases. The introduction of the borderline category in thyroid tumor classification will open a new era for pathologists in the diagnosis of thyroid nodules that have equivocal microscopic features.