Small-Sized Thyroid Cancers-a Single Institutional Experience in India

The incidence of small differentiated thyroid carcinomas is increasing worldwide in the recent years, especially tumours of size less than 2 cm in diameter. In this study, we have analysed the patterns of behaviour of small-sized thyroid carcinomas (<2 cm, T1 tumours) in comparison with large-sized thyroid carcinomas. This is a retrospectively analysed data of patients with thyroid carcinoma. The following parameters were analysed: distribution with regard to age, sex and the presence of metastasis based on radioiodine scan. The following histopathological details were collected: maximal tumour diameter, extrathyroidal extension and lymphovascular invasion. Out of 152 patients, 39 patients were excluded due to the non-availability of complete details. Among the 113 patients of thyroid carcinomas, 43 patients (28%) were presented with small-sized tumours (measuring less than 2 cm). In small-sized thyroid tumours, 21.6% showed extrathyroidal extension. 2.7% of the small-sized thyroid carcinomas showed perineural invasion as compared to 6.3% of the large-sized thyroid carcinomas. Twenty percent of the small-sized thyroid carcinomas showed lymphovascular emboli. 51.2% of the small-sized thyroid carcinomas were presented with nodal metastasis as compared to 40% of the large-sized thyroid carcinomas. 57.5% of the small-sized thyroid carcinomas showed extracapsular extension as compared to 57.8% of the large-sized thyroid carcinomas. Despite small size, thyroid carcinomas have properties to behave aggressively as comparable to large-sized thyroid carcinomas. Taking the above facts into account, the small thyroid cancers should be treated with considerable caution as large thyroid cancers, especially since we have limited tools to predict the preoperative poor prognostic factors.