Incidental thyroid carcinoma.

Objective: to find out the frequency of incidental thyroid carcinoma (ITC) in patients presumably operated for benign thyroid diseases.

Methods: a total of 187 patients undergoing surgery for benign thyroid diseases were included in the study. All the patients underwent fine needle aspiration cytology (FNAC). Only those with benign diseases on FNAC were studied. Patients with undetermined cytology and follicular neoplasm were excluded.

Results: Out of the 187 patients operated histology revealed ITC in 38 (20.3 %) of patients. The mean size of the nodule was 4.28 ± 1.48 cm in benign group and 4.21 ± 1.98 cm in ITC group. Papillary carcinoma was the commonest ITC (97.4 %) and follicular variant (16/38) was found more often than micropapillary variant (3/38). ITC was more common in patients with solitary nodule, 23 of 38 (60.5 %), although it wasn't statistically significant (P value 0.262) 0.33 of 38 (86.8 %) were in euthyroid state (P value 0.029).

Conclusions: the result of this study show, a high frequency of ITC (20.3 %). ITC was more frequent in euthyroid patients (P value 0.029). Incidence of ITC is not significantly different between patients presenting with SNG from those with MNG (P value 0.262). Papillary carcinoma was the commonest ITC (97.4 %) and follicular variant (16/38) was found more often than micropapillary variant (3/38).