Earlier detection of breast cancer by surveillance of women at familial risk

A positive family history increases the risk for breast cancer which often occurs at a much younger age than in the general population. We studied whe ther surveillance of these women resulted in the detection of breast cancer in an earlier stage than in symptomatic patients with a family history. Be tween January 1994 and April 1998, 294 women with 15-25% risk (moderate), m ean age: 43.3 (22-75) years, were screened with a yearly physical examinati on and mammography from 5 years before the youngest age of onset in the fam ily and 384 women with > 25% risk (high) for breast cancer, mean age: 42.9 (20-74) years were screened with a physical examination ever: 6 months and yearly mammography. From September 1995 breast magnetic resonance imaging ( MRI) was also carried out for 109 high risk women where mammography showed over 50% density. 26 breast cancers detected under surveillance were signif icantly more often found in an early T1N0 stage than the 24 breast cancers in patients with a family history referred in that period because of sympto ms: 81 versus 46% (P = 0.018). Patients under surveillance were also less f requently node-positive than the symptomatic group: 19 versus 42% (P = 0.12 ). 20 patients with a family history referred by our national screening pro gramme in that period had 21 breast cancers detected, 81% in stage T1N0 and 5% node-positive, which was comparable to the results in our national scre ening programme T1N0 66%, N+ 24% resulting in a 30% reduction in mortality. The incidence in women under surveillance was 10.1 per 1000 in the 'high' risk group and 13.3 per 1000 in the 'moderate' risk group. Expected inciden ce in an average risk population aged 40-50 years is 1.5, expected if the g roup consisted of only gene carriers 15 per 1000. 23% of the breast cancers in the surveillance group were detected at physical examination, but occul t at mammography. 38% were detected at mammography and clinically occult. B reast MRI tin the subgroup detected 3 occult breast cancers. The results of this study show that women with a family history benefit from surveillance as breast cancer was detected significantly more often in a favourable T1N 0 stage and a mortality reduction comparable to that obtained in our nation al screening programme may be expected also in women < 50 years of age. Bot h physical examination and mammography contribute to this result, but the f ormer in this study only contributed In women before menopause, Starting su rveillance some years before the youngest age of onset in the family may re sult in higher detection rates. Screening with MRI can detect breast cancer s, still occult at physical examination and mammography. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.