Ultrasonographic mass screening for thyroid carcinoma: A study in women scheduled to undergo a breast examination

This study was carried out to clarify the sensitivity of ultrasonographic m ass screening for thyroid carcinoma. Between December 1997 and July 1998, a total of 1401 subjects who were scheduled to undergo either a breast exami nation or a follow-up examination for breast cancer were enrolled in this s tudy. Patients with thyroid nodules were classified into two groups accordi ng to their potential risk for malignancy based on the ultrasonographic fin dings. Ultrasonographic high-risk patients for thyroid cancer underwent an ultrasound guided fine-needle aspiration biopsy (FNAB) and were advised to undergo a thyroidectomy based on the FNAB results. The characteristics of t he thyroid cancer patients detected by mass screening were then compared wi th those of 106 consecutive female patients with clinical thyroid cancer du ring the same period. Thyroid nodules were detected in 353 (25.2%) of the s ubjects, 94 (26.6%) of whom were placed in the highrisk group for thyroid c ancer. Among the 94 high-risk patients, 43 underwent a thyroidectomy and 37 turned out to have thyroid carcinomas. The detection rate for thyroid canc er was 2.6% for all subjects. The tumor size was significantly smaller than that of the clinically detected cancer group (P < 0.05). Ultrasonographic mass screening for thyroid carcinoma in women who require breast examinatio ns is thus considered to be effective for the detection of subclinical thyr oid carcinoma.