Rising incidence, no change in survival and decreasing mortality from thyroid cancer in The Netherlands since 1989

Abstract

The incidence of thyroid cancer (TC) is increasing worldwide, partly due to increased detection. We therefore assessed combined trends in incidence, survival and mortality of the various types of TC in The Netherlands between 1989 and 2009. We included all patients ≥15 years with TC, diagnosed in the period 1989-2009 and recorded in The Netherlands Cancer Registry (n=8021). Information on age, gender, date of diagnosis, histological type of tumour and tumour-node-metastasis classification was recorded. Mortality data (up to 1st January 2010) were derived from Statistics Netherlands. Annual percentages of change in incidence, mortality and relative survival were calculated. Since 1989 the incidence of TC increased significantly in The Netherlands (estimated annual percentage change (EAPC)=+1.7%). The incidence rates increased for all age groups (except for females >60 years), papillary tumours (EAPC=+3.5%), T1 and T3 TC (EAPC=+7.9 and +5.8% respectively). Incidence rates decreased for T4 TC (-2.3%) and remained stable for follicular, medullary anaplastic and T2 TC. Five-year relative survival rates remained stable for papillary (88%) and follicular (77%) TC, all age groups and T1-T3 TC (96, 94 and 80% respectively) and somewhat lower for T4 (53%), medullary (65%) and anaplastic TC (5%) in the 2004-2009 period compared with earlier periods. Mortality due to TC decreased (EAPC=-1.9%). TC detection and incidence has been rising in The Netherlands, while mortality rates are decreasing and survival rates remained stable or slightly decreasing.