Fine needle aspiration cytology in the management of euthyroid goitre.
The role of fine needle aspiration cytology was examined in a series of 115 euthyroid patients referred with thyroid enlargement presenting consecutively to a joint medical and surgical thyroid clinic from April 1985 to December 1986. Needle aspiration was performed at first clinic attendance and repeated two to six months later in 39 subjects. Patients were classified according to cytological features of the thyroid aspirate. A diagnosis of benign colloid goitre was made in 59 patients, lymphocytic thyroiditis in 11, thyroid cyst in 32 and in addition there were 13 reports of suspicious or malignant cytological features. Malignancy was confirmed histologically in six patients in this group and five more had follicular adenomata. There were two false positive reports of 'suspicious' cytological features. During a median period of observation of 11.4 months one false negative cytological diagnosis has emerged in a further patient with follicular adenoma. Accuracy in the diagnosis of thyroid neoplasia of 97 per cent has thus been achieved. Fine needle aspiration cytology has replaced isotope and ultrasound scanning in our practice. The number of 99mTc scans performed in the investigation of goitre fell from 77 in 1984 to three in 1986. Neoplastic tissue was removed at operation in 40 per cent of cases proceeding to surgery (20 subjects), compared with a predicted rate of 9.6 per cent if all solitary nodules had been removed. Aspiration cytology performed at first clinic attendance has led to improved selection of patients for surgery and hence economy in their management.