Age- and sex-distribution of primary thyroid cancer in relation to the histological type

Method: Data of all (239) patients suffering from thyroid carcinoma and ope rated on between January Ist, 1982, and Dezember, 31st, 1997 in our center, were analyzed retrospectively with respect to age- and sex-distribution in relation to the histological type of cancer. The change of frequency in th e histological groups was observed over a 16 years period. Results: From all 239 cases, 202 (84.5 %) were females and 37 (15.5 %) male s. The most common histological type with 70.3 % in both male and female wa s the papillary carcinoma, followed by follicular carcinoma with 21.6 % of male and 17.8 % of female patients. A medullary carcinoma was seen in 8.1 % and 5.9 %, respectively and an anaplastic carcinoma in only 5.9 % of femal e patients. There was no significant gender difference regarding the histol ogical type. In male patients the re was also no influence of age on histol ogical groups. Females with papillary and medullary cancer were significant ly younger than those suffering from follicular and anaplastic cancer. Besi de, we observed an increase in papillary and a decrease in anaplastic carci noma during the examination period. Conclusions: Although the relation of I male to 5 females with thyroid carc inoma shows a clear dependence on sex, the histological type distribution i s identical in both male and female. Therefore, several different factors s eem to influence the development of thyroid carcinoma. One of these factors depends on sex and supports an increased development of carcinoma in femal e patients. Another factor doesn't depend on sex and causes different histo logical types. Causes for that could be as well hormonal and reproductive o nes as regional differences in iodine availability.