D.V. Pasynkov1–3, М.А. Mikhaltsova1, 2, R.I. Fatykhov1, 2, О.V. Busygina1, 2, S.N. Merinov1, 2, Е.А. Romanycheva1, 2
1Clinical Oncology Dispensary of Mari El Republic, Yoshkar-Ola
2Mari State University, Yoshkar-Ola
3Kazan State Medical Academy — Branch Campus of the Federal State Budgetary Educational Institution of Further Professional Education «Russian Medical Academy of Continuous Professional Education», Ministry of Healthcare of the Russian Federation, Kazan
4Kazan State Medical University, Kazan
Pasynkov Dmitry V. — PhD (Medicine), Associate Professor, Head of the Department of Radiation Diagnostics of Republican Clinical Oncological Dispensary; Head of the Department of Radiation Diagnostics and Oncology of the Mari State University; Assistant of the Department of Ultrasound Diagnostics
22 Osipenko Str., Yoshkar-Ola, 424037, Russian Federation, tel.: +7-902-329-76-51, e-mail: passynkov@mail.ru
SPIN-code: 7264-3745, ORCID ID: 0000-0003-1888-2307
Abstract. Dense breast parenchyma represents an independent risk factor for breast cancer (BC) associated with 4–6 times increased BC morbidity. The aim of the work was to develop the approach to quantitative assessment of mammographic breast density and predict the risk of BC based on this value.
Materials and methods. We used the data from 140 patients with proven BC and 1255 screening mammography patients with no BC. The breast density was assessed according to the American College of Radiologists (ACR) classification, as well as by calculating the original continuous V1 index.
Results. We found no correlation of V1 values with the probability of BC in the subgroups of patients aged ≤45 years and from >45 to ≤50 years. In patients aged ≤45 years and >45 to ≤50 years V1 values with negative predictive significance for the BC were <0.39 and <0.34, recorded in 31 of 160 (19.38%) and 4 of 90 (4.44%) patients, respectively. In patients over 50 years, there was a weak but highly significant correlation between V1 values and the probability of BC (r2 = 0.150; p < 0.001). Here the V1 values with negative predictive significance for the BC were <0.33 (63 out of 1000; 6.3% of patients with no BC), and with positive predictive significance were >0.64 (1 out of 113; 0.88% of patients with BC). The 75th percentile of V1 values in patients with BC corresponded to 0.455. This value in patients with no BC corresponded to the 85th percentile. With this cutoff value, the probability of breast cancer in the risk group will also be significantly higher (14.4% compared to 7.7% among patients with V1 < 0.416; OR = 1.87; 95% CI: 1.32–2.64; p = 0.0004).
Conclusions. The proposed quantitative index of breast parenchyma density V1 exceeds the ACR classification, providing: 1) identification of premenopausal, perimenopausal, and postmenopausal patients with low V1 values as a low-probability group for BC; 2) identification of postmenopausal patients with V1 values ≥0.455 as a high-risk group for BC with a prediction accuracy of 55.97%.
Key words: breast, mammography, X-ray density, breast cancer, risk.