Increasing incidence of differentiated thyroid cancer in South East England: 1987-2006

There has been a worldwide increase in the incidence of thyroid cancer (TC). Documenting these recent trends is of immense value to cancer control measures, monitoring policies, improving clinical outcomes, resource allocation and stimulating research. Hence this study aimed to analyse the changes in incidence, staging and morphologic types of TC in South East England (1987-2006) by means of a retrospective, descriptive epidemiological study using anonymized data obtained from the Thames Cancer Registry (TCR) of all patients registered with TC in the period 1987-2006. Ethical approval was obtained from the Kent Research Ethics Committee. 4,880 anonymized datasets using the ICD-10 code for thyroid cancer (C73) were analyzed using SPSS v.17. TC was commoner amongst females 3,560 (73%) than males 1,320 (27%) with a 2.7:1 ratio. Mean age at diagnosis was 53 years (Range 5-99) years. An increasing incidence trend was observed in early stage disease (p < 0.001), in young adults aged ≤ 49 years (p < 0.001) and in well-differentiated TC (papillary p < 0.001 and follicular p = 0.03). The results showed that TC is commoner in females than males in SE England with a 2.7:1 ratio. The results also indicate that TC incidence has increased in SE England over the 20 years studied, with the greatest increase occurring in early stage disease, in females, young adults and well-differentiated types (papillary and follicular). This may be due to widespread usage of ultrasound with detection of incidental nodules. Further studies are required to explain the trend.