This study will conduct a multicenter, open, prospective clinical trial to observe the RecurIndex to assist in predicting the risk of recurrence in patients with early-stage Luminal-type breast cancer. The aim of this study is to validate the predictive effect of the RecurIndex on the risk of recurrence in women with early-stage Luminal-type breast cancer in China.

Inclusion Criteria:

• Age ≥ 18 years old, ≤ 70 years old.
• Eastern Cooperative Oncology Group (ECOG) ≤ 2.
• Postoperative pathology is clearly diagnosed as invasive breast cancer.
• Estrogen receptor (ER) or progesterone receptor (PR) positive, HER2 negative.
• Available with Formalin-Fixed and Parrffin-Embedded (FFPE) tumor tissue.
• Stage I-II patients who have received surgery (breast-conserving or mastectomy) and the pathological staging is pT1-2N0-1M0 or pT3N0M0.
• The patient had not received systemic systemic treatment (including radiotherapy, chemotherapy, immunotherapy, endocrine therapy) before enrollment.
• Signed an informed consent form.

Exclusion Criteria:

• Breast cancer patients whose clinical or pathological stage is T4, N2-3 or M1.
• Known human immunodeficiency virus infection (HIV) or acquired immunodeficiency syndrome (AIDS) related diseases.
• Other psychiatric disorders that may interfere with the judgment of the study results, or abnormal laboratory tests; and who, in the judgment of the investigator, are considered unfit to participate in the study.
• Patients with double breast cancer.
• Severe/uncontrolled intercurrent diseases/infections.
• Subjects with allogeneic organ transplants requiring immunosuppressive therapy.
• Hormone receptors ER and PR are negative (any detectable estrogen and progesterone receptors do not express or express <1%) and/or HER2 overexpression/amplified by FISH detection.
• Not suitable for hormone receptor modulators (e.g. tamoxifen) and adjuvant endocrine other drug therapy.

Women with breast cancer