Incidental thyroid carcinoma in a large series of consecutive patients operated on for benign thyroid disease.
BACKGROUND
The diagnosis of incidental thyroid carcinoma (ITC) in patients operated on for a benign disease is frequent. This study aims to determine both its clinical effect and the possibility of identifying this class of patients preoperatively.


METHODS
A total of 998 consecutive patients (697 women and 301 men; mean age, 49.5 years) undergoing surgery for benign thyroid pathology in a single institution were studied. The mean time between first diagnosis of thyroid disease and operation was 9.0 years (range, 0-50 years). All patients underwent at least one ultrasonography before surgery, and 678 patients underwent fine-needle aspiration cytology. Patients with undetermined cytology or follicular nodules were excluded from the study.


RESULTS
Histology revealed an ITC in 104 patients (10.4%): 99 had a papillary carcinoma. Mean and median diameters of ITC were 1.4 and 0.7 cm, respectively (range, 0.1-7.5 cm). In 43 patients, the tumour size was greater than 1 cm, whereas it exceeded 2 cm in 25 patients. Tumours were multicentric in 19.8% of the patients and occurred in 8.2% of patients with nodular toxic goiter, 8.7% of patients with toxic diffuse goiter and 13.8% of patients with multinodular goiter.


CONCLUSIONS
The results confirm the high frequency of ITC. ITC was more frequent in euthyroid patients than in thyrotoxic patients (P < 0.03). Sex, age, thyroid volume and interval between diagnosis and surgery did not significantly influence its incidence. The majority of ITC was represented by microcarcinomas, but in approximately 25% of patients, the tumour size was greater than 2 cm. The role played by FNAC in excluding malignancies proved to be fairly inconclusive.
Miccoli
Paolo
P
Department of Surgery, University of Pisa, Pisa, Italy.
Minuto
Michele N
MN
Galleri
David
D
D'Agostino
Jacopo
J
Basolo
Fulvio
F
Antonangeli
Lucia
L
Aghini-Lombardi
Fabrizio
F
Berti
Piero
P
D000293:Adolescent; D000328:Adult; D044963:Biopsy, Fine-Needle; D001707:Biopsy, Needle; D002291:Carcinoma, Papillary / Q000453:epidemiology / Q000601:surgery; D015897:Comorbidity; D005260:Female; D006042:Goiter / Q000453:epidemiology / Q000601:surgery; D006801:Humans; D033162:Incidental Findings; D008297:Male; D011446:Prospective Studies; D013959:Thyroid Diseases / Q000453:epidemiology* / Q000601:surgery*; D013964:Thyroid Neoplasms / Q000453:epidemiology*; D013965:Thyroidectomy