We have demonstrated marked weight gain after treatment of hyperthyroidism. Pre-existing obesity, a diagnosis of Graves' disease and prior weight loss independently predicted weight gain and weight continued to rise with time. Patients who became hypothyroid, despite T4 replacement, gained most weight.

In view of continuing debate regarding the best definitive therapy for thyrotoxicosis, we examined the long-term outcome of radioiodine (131I) or surgical treatment of 1918 thyrotoxic patients divided into three groups: those given 131I at a dose calculated from thyroid size, 131I uptake and effective half-life to administer a fixed radioactivity dose to the thyroid; those treated with a dose of 131I (110, 185 or 370 MBq) chosen empirically; and those treated by partial thyroidectomy. A minimum 10-year follow-up was achieved for 1119 patients treated with a calculated 131I dose; a single dose resulted in control of disease in 90.5%. At 5 years, 18% were hypothyroid, the prevalence rising to 42% at 20 years. Of 504 patients treated with an empirical 131I dose and followed for at least 5 years, thyrotoxicosis was controlled by a single dose in 89.7%. The rate of hypothyroidism at 5 years (38.5%) was higher than that found in the calculated dose group. A minimum 10-year follow-up was achieved for 295 surgically treated patients; thyrotoxicosis was controlled in 89.2%. The prevalence of hypothyroidism (2% at 5 years, 27.5% at 20 years) was lower than that found after 131I, whether given by calculated or empirical dose. Each of the treatments employed resulted in an acceptable rate of cure of thyrotoxicosis. If maintenance of euthyroidism is the major objective, our findings suggest that surgery represents the treatment of choice. Furthermore, calculated dose 131I administration has advantages in terms of risk of hypothyroidism over empirical dose treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

One thousand five euthyroid patients (870 females and 135 males, mean age 47 years), who presented with thyroid enlargement were evaluated by fine-needle aspiration cytology (FNAC) of the thyroid as the first-line investigation. The final cytological or histological diagnosis was determined after surgery (n = 312) or clinical follow-up for a minimum period of 2 years (range 2-14 years, mean 6.7 years). Goiter type was assessed clinically and was classified as diffuse in 147, multinodular in 247, or solitary nodule in 611. The overall sensitivity and specificity of the procedure in the detection of thyroid neoplasia was 88% and 89%, respectively. Males who presented with thyroid enlargement had significantly higher rates of malignancy (p = 0.007) and neoplasia (benign + malignant) (p = 0.002) than females, as did subjects with solitary nodule compared with diffuse or multinodular goiters (malignancy p = 0.001, neoplasia p < 0.001). Subjects with normal thyrotropin (TSH) (>0.4 mU/L) at presentation had a nonsignificantly increased risk of thyroid neoplasia (p = 0.07) and malignancy, in contrast to those with low TSH (<0.4 mU/L). We confirmed FNAC of the thyroid to be an accurate test in the detection of thyroid neoplasia. Gender and goiter type at presentation both contribute significantly to the prediction of the diagnosis of thyroid neoplasia.

No abstract

In otherwise euthyroid patients presenting with thyroid enlargement, reduction in serum thyrotrophin (TSH) concentrations measured in a sensitive assay may be a marker of thyroid autonomy and may therefore indicate a benign underlying pathology. We investigated prospectively a cohort of 467 subjects presenting consecutively to our thyroid clinic with nodular or diffuse enlargement of the thyroid. Subjects were divided into those with normal (0.4-5.5 mU/l), low but detectable (0.1-0.39 mU/l) or undetectable (< 0.1 mU/l) serum TSH concentrations. The final pathological diagnosis was defined by fine-needle aspiration cytology and clinical follow-up of at least 2 years or by fine-needle aspiration cytology and histology following surgical treatment. Serum TSH concentrations below normal were found in 75 patients (16.1%), those with low serum TSH results having higher mean free T4 concentrations, were older and were more likely to be female. In those with undetectable serum TSH, no patient had a diagnosis of thyroid neoplasia and in those with low but detectable TSH, thyroid neoplasms were diagnosed in two patients (3.4%). In those with normal serum TSH, 12.0% had a final diagnosis of thyroid neoplasm (p = 0.013). Overall, thyroid malignancy was found in one patient (1.3%) of those with a serum TSH measurement below the normal range and 6.9% of those with normal serum TSH (p < 0.06). Reduction in serum TSH at presentation may identify a group which requires less intensive investigation and follow-up than those without biochemical evidence of thyroid autonomy.