Diagnosis and treatment of the solitary thyroid nodule. Results of a European survey.

BACKGROUND AND OBJECTIVE: The optimum diagnostic and therapeutic strategy for the euthyroid patient with a solitary thyroid nodule is still a matter of debate. The aim was to assess the attitudes towards management of such patients in clinical centres throughout Europe by means of a questionnaire.

DESIGN: The questionnaire was circulated to all clinical members of the European Thyroid Association (ETA). A case report was followed by diagnostic investigations and choice of therapy in the index case (a 42-year old woman with a solitary 2 x 3 cm thyroid nodule and no clinical suspicion of malignancy). Eleven variations of the basic case report were proposed in order to evaluate how each alteration would affect management.

MATERIAL: 151 members replied to the letter and 110 individuals from 20 countries completed the questionnaire (corresponding to approximately two-thirds of the clinical members of the ETA). They represented clinicians who had diagnosed and treated more than 50 (76%) or less than 50 (24%) patients with nodular thyroid disease within the previous 6 months.

RESULTS: Based on the index case, basal serum TSH was the routine choice of 99% and serum T4 and/or free T4 were included by 70% of the respondents. Almost 50% included determination of serum thyroid autoantibodies (TPOab: 47%, Tgab: 26%) and 43% measured serum calcitonin. Thyroid scintigraphy was used by 66% (99mTc: 86%, 123I: 10%, 131I: 4%), ultrasonography (US) by 80% (size: 75%, grey scale: 57%, Doppler: 33%). Scintigraphy in addition to US was used by 58%. Fine-needle aspiration biopsy (FNAB) was routinely used by 99% of the respondents, and performed under US-guidance by 42%. Based on the individually chosen diagnostic tests indicating a benign solitary thyroid nodule, a nonsurgical strategy was advocated by 77%. Despite controversies on L-T4 treatment this treatment was supported by more than 40% of the clinicians. Surgery was advocated by 23% and the preferred technique was hemithyroidectomy (70%). Clinical factors raising suspicion of thyroid malignancy (e.g. family history of thyroid cancer, history of external radiation, rapid nodule growth and a large nodule of 5 cm) lead the majority (70-91%; P < 0.000001) to disregard FNAB results and to choose a surgical strategy.

CONCLUSIONS: The favoured diagnostic strategy in the workup of patients with a solitary thyroid nodule include determinations of serum TSH combined with serum T4 and/or free T4 followed by FNAB and US together with scintigraphy. A nonsurgical strategy was favoured by the majority supporting the use of L-T4 as the first choice. In case of clinical factors raising the likelihood of malignancy, the majority recommended diagnostic thyroidectomy despite FNAB suggesting a benign condition.