Abstract
BACKGROUND: Mammography, used for breast cancer (BC) screening, has limitations such as decreased sensitivity in dense breasts. Currently used tumor markers are insufficient in diagnosing breast cancer. In this study, we aimed to investigate the relationship between serum levels of synaptophysin-like protein 1 (SYPL1) and BC and compare SYPL1 with other blood tumor markers. METHODS: The study group consisted of 80 female patients with a histopathological diagnosis of invasive BC who received no radiotherapy/chemotherapy. The control group was 72 women with no previous history of breast disease and evaluated as Breast Imaging Reporting and Data Systems (BI-RADS 1-2) on imaging. Serum SYPL1, cancer antigen 15-3 (CA 15-3), and carcinoembryonic antigen (CEA) were measured in both groups.