In summary, we constructed a new risk score model using machine learning arithmetic based on 11 prognostic-related CSRGs (POLR2K, PYCARD, HSPA8, NFKBIE, EIF2AK2, JUN, CCL5, IL18, PRKDC, IFNG, IL33) to effectively predict prognosis and immunotherapy benefits in breast cancer patients. The gene discussed is HSPA8; the disease is breast cancer.