Aim: The aim was to determine: the final outcome of the well-differentiated carcinoma (cure/ persistent disease/ progression) with respect to the size of the nodule, the occurrence of metastases in the well-differentiated carcinoma, and the outcome by gender. Materials and Methods: Data used for processing were collected at the Department of Nuclear Medicine, University Hospital Split in the five-year period of 2008 - 2013, in 423 patients with thyroid cancer. Discernment criteria that were used were: well-differentiated cancers, the size of the node (up to 40 mm and greater than 40 mm), complications, initial metastases and gender, and thus obtained a sample of 259 patients with well-differentiated thyroid cancer. Program Microsoft Excel was used for processing data. Results: The most common well-differentiated carcinomas (97%) have nodes size up to 40 mm. From a total of 259 patients with well-differentiated thyroid carcinoma, in 243 patients (94%) ablation was noted, and re-ablation occurred in only 32 of them (13%). Postoperative complications were found in 70 patients (27%), where 90% refers to hypoparathyroidism, and in 10% of patients there was an appearance of metastases. Well-differentiated thyroid cancer was noted most common in women (79%). The incidence of postoperative complications was found higher in women (82%) with nodes up to 40 mm, and the occurrence of metastases was twice as common in women (69%) than in men (31%). Conclusion: Given the initial hypothesis that patients with nodes size over 40 mm have a higher number of metastases and poorer outcomes later (higher number re-ablation and more complications) analysis of the data showed the opposite. The worst outcome of a well-differentiated carcinoma in patients was determined where nodes were size to 40 mm. In these patients the occurrence of: re-ablation, complications and frequent metastases, had the most percentage. It was found that the impact of gender is an important factor and also it was determined that in women with nodes to 40 mm incidence of well-differentiated carcinoma and metastatic complications is far greater than in men.