Trends in thyroid cancer incidence and mortality in Central Serbia, 1999-2014

Thyroid cancer (TC) is the most common malignant disease of the endocrine system. The incidence of the TC has been increasing worldwide, especially in female population. However, mortality from TC is low in both males and females. The objective of the paper was to determine and to analyze incidence and mortality trends of TC in males and females in the central Serbia in the period 1999-2014.

In this descriptive study data from the Serbian Cancer Registry were used. Crude and age-standardized rates (ASRs) of incidence and mortality were calculated. Trend and annual percentage change (APC) of the incidence and mortality rate with corresponding 95% confidence intervals (CI) were calculated by performing Joinpoint regression analyses.

A total number of new cases of TC was 3113. TC was diagnosed in 2343 females and 770 males (female-to-male ratio, 3:1). A total number of fatal cases was 770 (while 504 female and 266 male died from TC, female-to-male ratio, 1.9:1). TC was not common before 30 years of age. The highest incidence was recorded both in males and females aged 50-59. Joinpoint regression analysis showed the statistically significant increase of ASRs of TC incidence in males in 1999-2014 period with APC 6.2% (95% CI: 4.2-8.3, p < 0.001) and there was also significant increase of ASRs of TC incidence in females in the same study period with a APC 6.1% (95% CI: 4.2-8.0, p < 0.001). Joinpoint regression analysis showed an insignificant increase of ASRs of TC mortality in males with APC 2.4% (95% CI: -0.5-5.5, p = 0.1). There was an insignificant decrease of ASRs of TC mortality in females with APC -1.3% (95% CI: -4.4-1.9, p = 0.4).

The increasing trend of age-standardized incidence rates of TC both in males and females and decreasing trend of age-standardized mortality rates during the observed period were registered. Females had higher age-standardized incidence and mortality rates than males. Female to male ratio of incidence was 3:1 and for mortality 1.9:1. Measures of primary and secondary prevention are needed.