[Mass-screening for ovarian cancer by means of transvaginal ultrasonography--study on size of ovary to select subjects requiring second screening].

Mass-screening for ovarian cancer by means of transvaginal ultrasonography has been performed in Aomori Prefecture since 1989. To select appropriate candidates to receive the second screening, the size of 44 normal ovaries removed by surgery and was measured studied on 10,692 ultrasonic pictures recorded on a VTR. The results were as follows: (1) All 44 ovaries were under 40mm. (2) In 3,806 (35.6%) of 10,692 women at the first screening, their ovaries were detected by ultrasonography. This detection rate was higher in young subjects and in the luteal and menstrual phases than in others. (3) Of these ovaries, 1,303 (34.2%) were under 19mm, 1,891 (49.7%) were 20-29mm and 614 (16.1%) were over 30mm in size. (4) The second screening was performed in 472 of the 614 women, and the size of the ovaries in 83 (17.6%) of them was under 29mm. (5) The frequency of ovarian size exceeding 40mm at the second screening, was 12.5% of the 30-39mm diameter group and 48.0% of the 40-49mm group at the first screening. There was no malignant tumor in the former, but there were one pre-malignant and one malignant tumor in the latter. These results indicate that the second screening should be performed for women having ovaries over 40mm in size.