Abstract P4-01-03: Digital measurement of mammographic density and the risk of overlooking cancer in Japanese women

Abstract

Abstract Introduction: mammographic density is a strong risk factor for breast cancer and an essential determinant of screening sensitivity, but the breast density of Japanese women has yet to be objectively examined. Single mammographic examination fails to detect approximately half of breast cancers in women with dense breasts. We objectively evaluated mammographic density to clarify the relation between breast density and incidence of breast cancer in Japanese women. Method: We enrolled 269 patients diagnosed with breast cancer and 397 healthy controls, who participated in screening mammography at Showa University Hospital. Breast density was measured using Volpara (a software application which analyses breast composition volumetrically). Results: The average age of both control and breast cancer groups was 55. Of the control group, 308 (78%) were characterized as having dense breasts, being defined as volumetric density grade (VDG) 3 or 4. More than 50% of the total population (all ages) had dense breasts (VDG 3 or 4) and more than 20% were extremely dense (VDG:4). Of the breast cancer patients, 232 (87%) were VDG 3 or 4. 52 (23%) of those with dense breasts showed negative results in single mammography examination. In primary breast cancer patients with dense breasts, 30% of those under age 70, but only 13% of those over age 70, showed no abnormal findings from mammographic examination. Conclusion and Discussion: In comparison of our present results and other papers, In the Japanese control group, 72% of patients had dense breasts (VDG 3 or 4) at age 50 or greater, but in Holland, for example, only 36% of women had breasts classed as dense. 87% of Japanese women with breast cancer had dense breasts, approximately the same ratio (88%) as found in Korea. For Japanese and other Asians, women under 70 years old with dense breasts may warrant additional screening. Citation Format: Sawada T, Ikeda M, Kuwayama T, Akashi ST, Nakamura S. Digital measurement of mammographic density and the risk of overlooking cancer in Japanese women. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-01-03.