[Mammography screening in Rogaland--the first round].

BACKGROUND

Screening with mammography is a proven method of detecting breast cancer at an early stage. In 1994, the Norwegian Ministry of Health and Social Services decided to initiate a trial with mammography screening in four counties before deciding whether to launch a national breast screening programme. Four counties were selected: Akershus, Oslo, Hordaland and Rogaland.

MATERIAL AND

METHODS

A detailed plan along with important determinants to evaluate the quality of the trial were agreed upon. The main-purpose was to find practical and administrative screening approaches which would result in a 30% reduction in mortality. Rogaland was the first county to start, in November 1995. The first screening round was completed in December 1997. We present the results from Rogaland and compare our results with the preset targets, and also with the results from the other three counties. A total number of 31,069 women aged 50-69 years were invited to participate.

RESULTS

The attendance rate was 88.6%. A total of 6.7% were referred for additional examinations; 4.9% were reexamined due to mammographic findings, the remaining 1.8% for technical or clinical reasons. The detection rate in our study was 8.4 cancers per 1,000 screened women. Of these, 6.1 were invasive cancer and 2.3 in situ cancer. 70.0% of the tumours were < or = 15 mm in diameter. In 82.1% there was no histologic evidence of axillary metastases. INTEPRETATION: We conclude that our diagnostic results from the first round of mammographic screening meet the quality target and are noticeably higher than those obtained by the other three counties. Based upon these results, we conclude that a reduction in mortality of 30% should be attainable.