Value of fine needle aspiration cytology in diagnosis of thyroid nodules at Kenyatta National Hospital
Abstract
Thyroid nodules are common at Kenyatta National Hospital. About five
new cases are seen weekly. The results of 398 consecutive Fine Needle
Aspiration Cytology (FNAC) of thyroid from 383 patients performed and
interpreted by different pathologists between 1st January and so" June 1997
were retrospectively reviewed and compared with their histologic findings.
The objective of the study was to assess the value of FNAC in the diagnosis
of thyroid nodules with emphasis on consistency and accuracy using
histology as the "Gold Standard". The study population consisted of 347
(90.6%) females and 36 (9.40/0) males. The age of the study population
ranged from 15 - 78 years. A total of 318 (87.10/0) FNAC had sufficient
material for Cytologic diagnosis. Of these 249 (78.3%) were benign
hyperplastic lesions. Only seven (1.83%) of the population studied were
diagnosed as cancers. Surgical confirmation of the Cytologic diagnosis was
obtained in 75 of the cases, of which 60 (80%) were accurately called benign
or malignant. A further 9 (150/0) cases who had unsatisfactory FNAC were
found to be benign. In 48 (64.00%) of the cases the cytologic diagnosis was
consistent with the histologic diagnosis. The calculated sensitivity was 80%,
specificity 1000/0, accuracy 98.60/0, positive and negative predictive values
were 100% and 98.8% respectively. There was one false negative and no
false positives.
The study shows that FNAC is a sensitive, specific, accurate and cost effective technique
in the management of patients with thyroid nodules. It
should be used along with clinical assessment as the first diagnostic
technique to determine the management of thyroid nodules at K.N .H.. This
would assist in selecting patients for surgery and a reduction in cost of
management of patients with thyroid nodules.
Citation
Master of Science in Clinical Cytology, University of Nairobi, 2001Publisher
University of Nairobi, Department of Human Pathology