Bilateral Synchronous and Metachronous Breast Cancer: Features of Topography, Etiology, Pathogenesis, Risk Factors, Diagnosis and Prognosis

Abstract

The purpose of the study was to analyze the data of the domestic and foreign specialized literature, which are devoted to the pathogenesis, features of the topography, risk factors, prognosis of the course of bilateral synchronous and metachronous breast cancer. Materials and methods. Analytical and bibliosemantic methods were used in the research. The search for scientific information on bilateral synchronous and metachronous breast cancer for the period from 1990 to 2021 was conducted in databases of electronic searching systems. Results and discussion. Bilateral cancer can be either primary or metastatic to the contralateral breast. Primary one, depending on the time of tumor development in the contralateral breast gland, is divided into synchronous (development interval up to 6 months) and metachronous (development interval more than 6 months). Synchronous tumors of the breast glands are found significantly less frequently (22.7%) than metachronous tumors (69.6%). Relative risk factors for the occurrence of bilateral metachronous breast cancer are the presence of a BRCA1 and BRCA2 gene mutation, a heavy family history of breast cancer in blood relatives, and a young age of up to 45 years. A higher risk was established in patients with a lobular histological type of carcinoma compared to ductal carcinoma and with the absence of expression of steroid hormone receptors in the tumor. Bilateral synchronous tumors are very often characterized by the same visual manifestations during mammography, and their location in the breast glands is a "mirror image". Metachronous tumors are characterized by a smaller size, with rare involvement of axillary lymph nodes. A peculiarity of the topography of metachronous breast cancer is the presence, mainly in the upper outer quadrants of the breast gland, of a fixed or slow-moving nodule of rounded or star shape with unclear contours. Magnetic resonance mammography of the glands is an effective method of comprehensive diagnosis of breast pathology and is performed when other imaging methods are ineffective (sensitivity 99.2%, specificity 97.9%, accuracy 98.9%). The duration of the recurrence-free period in patients with synchronous tumor was 126.3 months, while in patients with metachronous tumor it was 243.7 months. Conclusion. The problem of bilateral breast cancer remains complex and far from fully understood. There are many controversial issues related to the pathogenesis, risk factors, features of the topography, clinical and morphological manifestations, diagnosis, recurrence-free and overall survival of bilateral breast carcinoma, which is important for determining and evaluating the prognosis, as well as the choice of management tactics for such patients