5.3.1　Rescue Chemotherapy

For advanced breast cancer，if the patient meets one of the following factors，chemotherapy can be considered：hormone receptor negative；symptomatic visceral metastasis；hormone receptor positive，but resistant to endocrine therapy.The principle of rescue chemotherapy can be selected as a single drug or a combination of drugs，but the combination drug is often toxic and has limited survival benefits.Therefore，the guideline believes that only for patients who need rapid tumor shrinkage or rapid patient symptoms，combined chemotherapy is preferred.For patients with previous anthracycline treatment failure，the first choice for rescue chemotherapy is based on purple shirts；for patients who have failed treatment of anthrax and purple shirts，there is no standard recommendation in the current guidelines，but consider capecitabine，gemcitabine，etc.For triple-negative breast cancer，treatment can only take a different approach because of the lack of hormone receptors and HER-2 targets.An impassion 130 study in 2018 enrolled 902 inoperable advanced or metastatic breast cancers，randomly divided into atezolizumab and albumin-bound paclitaxel groups，placebo and albumin-bound paclitaxel groups at a ratio of 1∶1.The primary endpoint was the PFS assessed in the study.In the ITT population，the PFS in the experimental and control groups were 7.2 months and 5.5 months，respectively，and in the PD-L1 positive population，7.5 months and 5.0 months，respectively.The difference was statistically significant.Based on this study，the 2019 guideline recommends that triple-negative advanced breast cancer be actively involved in clinical studies of PD-L1 immunological checkpoint inhibitors，such as Impassion 131 currently underway.(https://www.daowen.com)

The Olympiad study［7］was a randomized，open phase Ⅲ clinical trial enrolling 302 patients with BRCA mutations and HER-2 negative advanced breast cancer，randomly assigned to the olaparib group at a 2∶1 ratio and in the control group（standard chemotherapy group），the primary endpoint of the study was PFS，and the results showed that the olaparib group significantly prolonged disease-free survival（median PFS：7.0 months vs 4.2 months，P＜0.001），based on this study，the 2019 guideline group recommended that patients with BRCA1/2 germline mutations be treated with olaparib or actively participate in relevant clinical studies.The BG01-1312L study［8］is an analysis comparing the efficacy and safety of UTD1 in combination with capecitabine and single-agent capecitabine.The patients enrolled in 405 anthracyclines from 25 hospitals in China.Metastatic breast cancer with failed treatment of vaginal discharge was randomly divided into UTD1 combined with capecitabine group and capecitabine monotherapy group at a ratio of 2∶1.The median follow-up time was 6.77 months and 4.55 months，respectively.Median progression-free survival was significantly longer in the UTD1 plus capecitabine group（8.44 months vs 4.27 months，p＜0.0001）.Based on this study，the 2019 guide mentions that UTD1 and capecitabine may be a new option for advanced breast cancer that fails to treat anthracyclines and shawls.