Thyroid cancer among goitrous patients in southwestern ethiopia: a hospital based histopathologic review

Abstract

Thyroid cancer is the most common endocrine cancer (accounts for 95% of all endocrine cancers) and its incidence has continuously and sharply increased in the last six decades all over the world. There are four histologic types of thyroid cancer: papillary, follicular, medullary and anaplastic. The distribution of the histologic type varies from country to country based on radiation exposure status and rate of goiter. Goiter is a pathological condition with epidemic dimensions in some areas because of several factors like geographical, nutritional, and genetic factors which has been linked to a higher risk of thyroid cancer, especially for the follicular histotype. Goiter is a major concern in many parts of the world, including Ethiopia and therefore taking a prevention measures may reduce the rate of progression to cancer. Objective- The aim of this study was to describe the histopathologic pattern of thyroid cancer among goiterous patients in Jimma University spcialized Hospital, Southwestern Ethiopia, over a five years period, from 1st Sep. 2010 to 31st Aug. 2015 G.C. Methods- retrospective study was carried out at Jimma University specialized hospital, department of pathology, over a period of five years from 1st Sep. 2010 to 31stAug.2015 G.C. All patients who proved to have cytohistopathologic features of thyroid cancer (cancerous goiter) was included in the study. All data including age, sex, fine needle aspiration cytology, type of goiter (nodularity by clinical diagnosis), and final histopathology report for non-diagnostic or suspicious malignancy results by FNA reports were documented on standard form. Result –seventy five (75) patients with thyroid cancer were included in this study; out of this 29 (38.7%) were found to be papillary and 27 (36%) were follicular cancer followed by anaplastic and medullary ca with a rate of 20 %( 15) and 2.67 %( 2) respectively. Generally a female preponderance has been noted among the cancerous patients, with a female-to-male ratio of 1.6:1. From all thyroid cancer diagnosed patients 3 (2.7%) patients were found to be toxic by biochemical tests and clinically 39 (52%) of the patients appeared with discrete (solitary/dominant) nodular goiters. Conclusion and recommendation.- Unlike the belief that thyroid cancer is a rare disease, it was seen in 75 (8.3%) of patients with goiter. Papillary ca is the most frequent cancer seen in this series. Toxicity is a negligible or a very rare event in thyroid malignancies. Clinical evaluation of goiters should be thorough, and use all means esp. histopathology study of the specimen to arrive at definitive diagnosis, as thyroid ca is not uncommon.