As the research on tumors continues to advance, it has been found that the malignant behavior of tumors, including infiltration, metastasis and drug resistance, involves the synergistic effects of multiple genes. Therefore, to some extent, the detection of individual genes cannot accurately and comprehensively evaluate the prognosis of tumor patients. The ideal method should be to analyze the expression status of multiple related genes in an integrated manner, which can more truly reflect the patient’s own condition. In terms of genetic testing of breast cancer, besides 21-gene RS, Xinjiang Cancer Hospital Breast Surgery Department Ou Jianghua also has a multi-gene testing technology – MammaPrint, the former is to detect 21 genes by fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR), and the latter is to detect 70 genes by high-throughput gene microarray to detect 70 genes. Gene recurrence score: The introduction of the 21-gene recurrence score (RS) has caused quite a stir in the international academic community. A retrospective analysis of two studies (NSABP B-14 and B-20 studies) found that the 21-gene RS predicted the benefit of adjuvant chemotherapy and that high-risk individuals could benefit from chemotherapy, so the 2008 National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines for Breast Cancer recommended that adjuvant chemotherapy could be avoided for patients determined to be at low risk based on the 21-gene test. The 21-gene test is now widely used in the U.S. The main significance of 21-gene RS is to avoid waste of resources and overtreatment of some low-risk patients. (1) About 21-gene RS a The RS score (0-100) is determined by analyzing the expression of 21 genes, and patients with RS <18, 18≤RS≤30, and RS≥31 are considered low-, intermediate-, and high-risk patients, respectively. b The 2008 edition of the NCCN Clinical Practice Guidelines for Breast Cancer states that for patients with ER-positive, HER2-negative, axillary lymph node negative, tumor size of 0.6-1.0 For patients with ER-positive, HER2-negative, axillary lymph node-negative, tumor size 0.6-1.0 cm with low- to intermediate-differentiation or poor prognostic factors, or tumor >1 cm, RS should be considered for further analysis and postoperative adjuvant chemotherapy (Category 2B) should be given to high-risk patients; adjuvant chemotherapy can be avoided for patients with low risk according to 21-gene testing. c In the United States, the cost of the test is approximately $3820. However, it should be noted that this means of testing is not necessarily applicable in our country. This is because: firstly, the above conclusions were drawn from a retrospective study and their credibility needs to be further established; secondly, the subjects selected for the study were themselves low-risk patients (hormone receptor positive, axillary lymph node negative) who may not have required chemotherapy, so 21-gene RS is only used as an elective test; thirdly, most patients in China cannot afford the price of the test and most patients are already at intermediate to high risk at the time of diagnosis. Third, most patients in China cannot afford the price of the test, and most patients are already at intermediate to high risk at the time of diagnosis, so the application of this technology is limited. Based on the above considerations, during the discussion of the revision of the 2008 edition of the NCCN Clinical Practice Guidelines for Breast Cancer (Chinese version), the Chinese expert group generally agreed that although 21-gene RS has some theoretical significance, it is difficult to carry out based on the current situation in China, and further validation is still needed, so it is not strongly recommended. (2) About MammaPrint a a gene chip for assessing breast cancer prognosis based on the well-known 70 breast cancer gene markers in Amsterdam; b In 2007, it was approved by FDA for predicting the risk of recurrence and distant metastasis in lymph node negative breast cancer patients within 5-10 years; c Unlike 21-gene RS (the test is available for both fresh and fixed tissues), the Mammaprint assay is limited by fresh tissue, and samples must be taken from non-fixed tumor specimens within 1 hour of surgery. d In the United States, the cost of the test is approximately $4,200.