RESUMO
This work was intended to evaluate the result of fine needle aspiration biopsy from nodular thyroid diseases and to study the effect of thyroxin suppressive therapy on benign nodules. The study included 40 patients with thyroid nodules [gP1] and 10 control subjects matched for age and sex [gP2]. Subjects were selected from those attending the endocrinology and surgery outpatient clinics of Alexandria Main University Hospital. All subjects and control were subjected to the following: thorough history taking, complete physical examination, estimation of ultrasensitive TSH [ELISA] basal, 3 and 6 months after thyroxin therapy, FT[4] [Automated Chemiluminescent System], FT[3] [Automated Chemiluminescence System]. Thyroid ultrasound was performed for all patients for the detection of solid or cystic nodules, solitary or multiple nodules, for confirming the presence of retrostenal extension and for calculation of the volume of nodules according to the following formula: Volume of nodule = length x width x thickness x 0.48. NAB from thyroid nodules was done. Patients fulfilling the following criteria have been subjected to thyroxine suppressive therapy:[1] Solid nodule on ultrasound, [2] benign colloid nodules confirmed by FNAB, [3] euthyroid or hypothyroid patients confirmed by FT[3], FT[4], TSH, [4] no contraindication to thyroxine therapy. The dose of levo-thyroxine which is adjusted to obtain a modest suppression of TSH to between 0.1 and 0.5 mlU/L was 1.7 +/- 0.9 micro g /Kg/day. The follow up of patients was performed at 3 and 6 months as regards the nodule volume by ultrasound and measurements of TSH. After history taking 3 patients had history of head and neck irradiation, 12 patients had family history of goiter and 13 patients had pressure manifestations. Ultrasound examination revealed 13 patients with solitary nodule and 27 patients with multiple nodules. There were no significant correlations between thyroid nodule volume and the measured hormones, also no significant correlations were found between volume of thyroid nodule and TSH 3 and 6 months after treatment. FNAB was performed for all patients and revealed that 22 patients had colIoid nodules, 2 patients had papillary carcinoma, 5 patients had lymphocytic thyroiditis, 5 patients had follicular proliferative lesions and the rest 6 patients had thyroid cyst. Thyroidectomy was performed for fifteen patients [2 with papillary carcinoma, 5 with follicular proliferative lesions, 6 with cysts and 2 with huge colloid goiter] and histopathological examination was done and compared to FNAB results to assess the sensitivity, specificity and overall accuracy. Twenty three patients took thyroxine suppressive therapy for 6 months and nodule volume measured by ultrasound revealed non significant progressive decrease in volume while the TSH was significantly decreased after 3 months and 6 months. FNAB is reliable, sensitive and specific, it should be performed on all patients with palpable thyroid nodules. - Suppression of the nodular thyroid with thyroxine is not beneficial in most patients thus its use should be discouraged. - Long term controlled studies of thyroxine suppressive therapy are needed to answer the debate about suppressive therapy