Sacituzumab Govitecan + Toripalimab as First - Line Therapy for Advanced Triple - Negative Breast Cancer and Biomarker Exploration

1\. Research Objectives： The overall objective of this study is to explore the efficacy and safety of sacituzumab govitecan in combination with toripalimab as first - line treatment for advanced triple - negative breast cancer. Primary Objectives：1）To observe and evaluate the efficacy (progression - free survival, PFS) of sacituzumab govitecan in combination with toripalimab as first - line treatment for advanced triple - negative breast cancer under real - world conditions.2）To observe and evaluate the safety (all adverse events and immune - related adverse events) of sacituzumab govitecan in combination with toripalimab as first - line treatment for advanced triple - negative breast cancer under real - world conditions. Secondary Objectives：Objective response rate.Survival.To observe and explore biomarkers associated with efficacy. 2. Significance of the Research：Currently, chemotherapy remains the main treatment for advanced triple - negative breast cancer. However, whether it is single - agent or combination chemotherapy, the efficacy is rather poor. Improving the efficacy and safety of first - line treatment for advanced triple - negative breast cancer is an urgent problem to be solved. Both sacituzumab govitecan and toripalimab are major drugs for the treatment of advanced triple - negative breast cancer, and combination therapy may further enhance the effectiveness of treatment. At present, there is no literature reporting the efficacy and safety data of sacituzumab govitecan in combination with toripalimab as first - line treatment. This study is a prospective, single - arm, multicenter, non - interventional, observational clinical trial, aiming to observe the efficacy and safety of sacituzumab govitecan in combination with toripalimab as first - line treatment for advanced triple - negative breast cancer in the real world.