Incidental thyroid carcinoma includes thyroid carcinomas detected after surgery in patients whose thyroid has been correctly studied with no data of malignancy. Lately, the widely spread use of image techniques and thorough search of thyroid nodule complains, have lead to a growing number of thyroid carcinomas. But still there are some of these incidentally discovered after thyroidectomy.
We report 98 cases of thyroid carcinomas incidentally found from a series of 360 thyroid carcinomas (27.2%), diagnosed since 1992. Demographic data, thyroidectomy criteria, histopathology, tumour size, multicentric cases, extension, radioiodine treatment and follow up data were collected.
Our results show a mainly female cohort (81.6%), with ages ranging from 21 to 81 years (mean 51.29 and median 31). First 3 cases detected in 1994 and ever since the number has been increasing (14 cases in 2008, 11 in 2009 and 11 in 2010). The criteria for thyroidectomy was nodule size with bening cytology (87.7%), associated hyperparathyroidism (6.2%) and hyperthyroidism (3%). Hystopathology result was Papillary thyroid carcinomas (PTC) in 96%. Mean tumour size was 13.5 mm and median of 7 mm, ranging from 1 to 75 mm. Multicentric cases were found in 27.5%. Extra thyroid extension was recorded in 15.3% cases. Radioiodine treatment (131I) was used in 80.8% of PTC. During the years of follow up there has been only one death.
Incidental tumours are more common in women of young mean age. PTC of small size, not multicentric and not extended out of the thyroid is the main outcome after thyroidectomy. Most of them underwent 131I treatment. Due to the described features the general prognosis of these cases is good. Careful hystopathologic analysis and standard treatment and follow up is our basic approach. Probably 131I shows overused in our series since retrospectively it was more used in the past.