Increase incidence of thyroid cancer in Florianopolis, Brazil: comparative study of diagnosed cases in 2000 and 2005.

OBJECTIVE To provide epidemiological information about thyroid cancer (TC) in the Metropolitan area of Florianopolis and investigate some factors that could be associated with this type of cancer. METHOD This study analyzed data of patients who had TC diagnosed and underwent surgical treatment in 2000 and 2005. Epidemiological factors about patients, tumors and surgical procedures were evaluated. RESULTS In 2000 and 2005, an increasing incidence of TC at a rate of 132.33% was detected. The increased rate was mainly observed for tumors measuring less than 1 cm (p = 0.004). Results also showed an increase in the number of multifocal tumors (p = 0.02) and in the rate of total thyroidectomy (p = 0.002). CONCLUSIONS The increasing incidence of TC in the Metropolitan area of Florianopolis is probably due to more invasive thyroid nodule management. Future studies are necessary to establish potential predicting factors for papillary thyroid microcarcinoma aggressiveness, as well as predictors of follicular lesion malignancy to identifying more accurately the appropriate therapy approach.