New evidence about thyroid cancer prevalence: prevalence of thyroid cancer in younger and middle-aged Japanese population

摘要

We have made a cross-sectional investigation of men in the Japanese military for the presence of thyroid abnormalities and thyroid cancer to document the prevalence of thyroid disease in these persons. Six thousand, four hundred and twenty-two Japanese military men and women were screened for thyroid disease by history, physical examination and ultrasound examination. Among them, 6,182 were men 50 years of age, 47 were women 50 years of age, and 149 were men 40 years of age and 44 were women 40 years of age. Among the 50 years old men, thyroid nodules were found in 924 men (14.9%): Nineteen individuals (0.31%) had thyroid cancers ranging from 1 mm to 30 mm in diameter (12.5 mm in mean), pathological TNM staging revealed 7 cases of stage I, 2 cases of stage H and 9 cases of stage HI. There was a significant increase in thyroid nodules in 50 years old men compared to that in 40 year old men, but there was no significant difference between men and women (p>0.05). Our data document that the detection rate of thyroid cancer in 50 years old men was 0.31%, and the rate of thyroid nodules increased with age in men, but the frequency of thyroid nodules were similar in men and women of the same age.