Value of repeated fine needle aspiration cytology in patients with nodular goiter.

OBJECTIVE: To assess the value of reaspiration cytology in benign nodular thyroid disease. DESIGN: We prospectively studied 400 patients (365 women, 35 men) aged 46 years (18-89) with nodular thyroid disease and initial benign fine needle aspiration cytology (FNAC). Reaspiration of the same nodule was performed in a median follow-up time of 14 months (6-18). RESULTS: Repeat FNAC was benign in 346 patients (86.5%), insufficient for diagnosis in 42 (10.5%), suspicious in 16 (2.5%) and malignant in 2 (0.5%). All diagnostic changes to suspicious malignant cytology took place in patients with solitary nodules. Surgery confirmed thyroid cancer in the 2 patients with malignant cytology, in 5 of 10 patients with suspicious cytology and in none of 39 patients with benign cytology who underwent surgery for other reasons. Clinical changes (size increase or local symptoms) were not related to changes in cytologic diagnosis after a second aspiration, nor with the results of the biopsy. CONCLUSION: Repeat aspiration cytology of thyroid nodules may correct initial false negative results because of cytologic misdiagnosis, occurring in 1.75% of patients, whereas clinical changes did not contribute to diagnosis change. Repeat aspiration cytology is recommended in all patients with nodular goiter.

Prognostic value of thyroglobulin serum levels and 131I whole-body scan after initial treatment of low-risk differentiated thyroid cancer.

Diagnostic iodine-131 whole-body scan ((131)I-WBS) and serum thyroglobulin values (Tg) performed 6 to 12 months after thyroid ablation for differentiated thyroid carcinoma were evaluated in 194 consecutive patients at the Hospital de Navarra, (Pamplona, Spain). All patients underwent near-total thyroidectomy and (131)I ablation with 3.7 GBq. Patients with positive anti-Tg antibodies or with (131)I uptake outside the neck were previously excluded. Uptake of (131)I in the thyroid bed was detected in 27 patients (13.9%). Serum Tg levels were below 0.5 ng/mL in 133 patients, ranged from 0.5-10 ng/mL in 39 patients, and was above 10 ng/mL in 22 patients. After a follow-up of 7.7 +/- 3.3 years, persistence of the illness has been observed in 2 patients with undetectable Tg (1.5%), but metastases were not detected in any case. In those with Tg higher than 0.5 ng/mL, 29 of 61 patients had persistence of the disease (47.5%) with evidence of metastases in 15 (24.5%), irrespective of the initial total body scan (131)I uptake. In conclusion, serum Tg levels obtained after thyroid ablation has a good prognostic value and permits the selection of patients for further diagnostic studies, while diagnostic (131)I-WBS performed at that time did not correlate with results of Tg and scarcely provides additional information.