Thyroid cancer incidence differences between men and women

Early-stage thyroid cancer is about 4 times more common in women than men, but the underlying subclinical prevalence is the same between the two sexes. As the lethality of the cancer type increases, the ratio in incidence for women compared to men approaches 1:1. These facts suggest that differences in healthcare utilization may be a major reason thyroid cancer is diagnosed more in women than men. Physiological elements could also contribute, as women have a higher prevalence of thyroid nodularity compared to men. Current research suggests estrogen does not play a major role, but genetics may be a potential reason for increased rates of thyroid cancer in women compared to men. Immune surveillance is greater in women and currently is thought to be protective against thyroid cancer development. This review summarizes recent evidence examining the role of these factors in modulating the sex-disparity observed in thyroid cancer incidence.