Abstract: Objective To analyze the clinicopathological characteristics of breast cancer. Methods The clinicopathological data of 3 514 patients who underwent surgery in Department of Breast and Thyroid Surgery of Provincial Hospital Affiliated to Shandong University during July 2010 and June 2018 were retrospectively analyzed. All information was obtained from the medical records. The clinicopathological characteristics were described and analyzed using the relative number and constituent ratio. Results The gender ratio(male/female)was 1.00∶318.45, median age of onset was 50, peak age of onset was 40-50, and the highest peak age was 45-50. Synchronous bilateral and multifocal/multicentric breast cancer accounted for 1.05% and 5.07% of all cases, respectively. The main pathological type was invasive ductal carcinoma, followed by intraductal carcinoma. There were significant differences in the constituent ratio of pathological types(P<0.001); interannual constituent ratio of TNM stage 0 and stage Ⅰ(P=0.004, P=0.009); annual constituent ratio of histological grade Ⅱ,Ⅱ-Ⅲ, and Ⅲ(P<0.001); annual constituent ratio of Luminal A, Luminal B and HER-2 positive(HR negative)types(P<0.001, P<0.001, P=0.032); constituent ratio of breast cancer complicated with hyperplasia of mammary glands(P=0.047); proportion of vascular invasion(P=0.018); and lymph node metastasis(P=0.003). Conclusion The clinicopathological characteristics of 3 514 breast cancer patients, including age of onset, gender ratio, pathological types, molecular classifications and stages over 9 years are elucidated, which can provide reference for the study of clinicopathological characteristics of breast cancer patients in Shandong Province.

Key words: Breast cancer, Pathological characteristics, Clinical features, Monocentric, Inter-annual variation