Breast Cancer Incidence by Age at Finding of Mammographic Abnormality in Women Participating in French Organized Screening Campaigns.

Abstract

Purpose: Using reduced samples, statistical modelling was already predicted the occurrence of Breast-cancer or its prognosis from previous radiological findings. This study aims to predict breast-cancer risk by mammographic abnormalities finding age in the French breast-cancer screening campaign. Methods: The study involved 261,083 women aged 50-74 living in French Departments (Ain, Doubs, Haute-Saône, Jura, Territoire-de-Belfort, Yonne). These women had at least two screening mammograms between Jan-1999 and Dec-2017 of which the first was classified as “normal/benign”. The incidence of mammographic-abnormality (microcalcification, spiculated-mass, obscured-mass, architectural-distortion, asymmetric-density) and the incidence of breast-cancer after abnormality detection were estimated abnormalities finding age, using an actuarial life-table method. Breast-cancer risk was predicted in a Cox multivariate model.Results: The incidence of mammographic-abnormality was 95.4[94.9; 95.9]/1000 person-years. Breast-cancer (6,326 cases) incidence was 3.3[3.0; 3.1]/1000 person-years. That incidence was 5 times higher in women who showed a speculated-mass vs. those who did not (6.9[6.4; 7.4] vs. 1.3[1.2; 1.3]). Whatever the abnormality, the incidence of cancer was higher when it was present in only one breast. Depending on the spiculated-mass finding age, the risk increased by at least 40% between the age groups 55-59years (1.4[1.0; 1.8]) and ≥70years (2.4[1.9; 3.3]).Conclusion: The study showed the increased risk of cancer with the abnormalities finding age and the low risk related to the presence of the same mammographic-abnormality in both breasts compared to the isolated mammographic-abnormality in one of the breasts. This should alert radiologists to the relevance of certain diagnostic procedures in the management of a bilateral mammographic abnormality.