Incidental thyroid carcinoma after thyroidectomy in patients with Graves’ disease

Aim–Background The association between Graves’ disease (GD) and thyroid cancer (TC) has been studied over the years with controversial results. The aim of our study was to define the prevalence of incidental thyroid cancer (ITC) among patients operated for GD, present the rates found in our department and suggest an efficient treatment modality. Methods We retrospectively reviewed 206 patients who underwent total thyroidectomy for benign thyroid disease in our department over a 6.5-year period. GD was diagnosed in 31 cases with a median age of 55 years. Small non-palpable nodules in the thyroid parenchyma were observed in eight subjects. Patients with a malignant or inconclusive fine-needle aspiration biopsy (FNAB) result were excluded. Results The histological examination incidentally revealed six (19%) papillary thyroid microcarcinomas (PTMC) out of 31 specimens with GD. ITC presented within a nodule in 37.5% (3/8) of the subjects with nodular parenchyma. No local or distant invasion was reported. Conclusions The rates of ITC have been seen to range from 1% to 42% in recent studies. Patients with nodular parenchyma show a greater risk of carcinogenesis, particularly when nodules are palpable. Papillary carcinoma and microcarcinoma constitute most of the cases of ITC. In our department, the rate of ITC was 19%, malignancy had developed only in female patients and 50% of the tumours were within a nodule. Regarding the treatment options of GD, total thyroidectomy represents a prompt and valuable choice. Furthermore, total thyroidectomy emerges as the optimal treatment option when the disease is combined with nodules and/or young age, considering the risk of disguised malignancy.