Thyroid cancer in Wales 1985-1996: a cancer registry-based study.

No dedicated clinicopathological database for thyroid cancer exists in Wales to provide information about the incidence, histology, treatment and outcome of this uncommon malignancy. We have used cancer registry data to examine the epidemiology of thyroid cancer in Wales between 1985 and 1996 and have searched the database for clinically relevant data about stage, treatment and survival. A total of 699 cases were identified in this 12-year period, with no significant differences in their distribution between the five health authorities. Further analysis revealed a very wide age range (8-93 years) with a predominance of females (F:M ratio 2.8:1) and survival strongly influenced by gender, age and histological type. There were insufficient data to stage these cancers and only limited data about the surgical procedures undertaken. There was no information on non-surgical treatments (radio-iodine, radiotherapy and chemotherapy) in the database. Cancer registry data is well able to sustain an analysis of the epidemiology of thyroid cancer but further work is necessary to improve the quality of clinically relevant information about stage and treatment that could be used for audit.