Histological Review of Thyroid Lesions: A 13-year Retrospective Study (1989-2001)

Objective: We present a 13-years retrospective histological study of 444 thyroidectomies received between 1989 and 2001 at the Morbid Anatomy department of the Lagos University Teaching Hospital, Nigeria. The aim of the study is to update the available literature on the frequencies of the common thyroid lesions as well as compare with previous studies. Materials and Methods: The materials for this study consist of slides and paraffin embedded blocks of all thyroidectomies received from within and outside the teaching hospital. The clinical data such as the age, sex, and clinical summary were extracted from the request forms. Results: The male: female ratio is 1: 7. The most common entity was goiter (74%); most of which occurred in the age group 30-39 yrs. Thyroid adenomas (majority; follicular), constituted 10%. There were 29 cases of thyroid carcinoma accounting for 7% of all lesions and occurring more in females than males (17:12). Histologically, follicular carcinoma predominated (48.3%), followed by papillary carcinoma (34.5%) and medullary carcinoma (13.8%). Thyroiditis was uncommon (only 2%). Conclusion: Goiter, adenoma and carcinoma remain the commonest pathologic entities of the thyroid gland in Lagos. The age and sex incidences as well as the histological characteristics concur with reports from other parts of Africa and Nigeria. However, unlike many of the Nigerian series except the latest from Ibadan, 4 cases of medullary carcinoma were encountered in this study. The frequencies of toxic hyperplasia and thyroiditis are also lower than those recorded in previous studies. Keywords: thyroidectomy, histopathology, thyroid lesions.