Q: Pyrrolizidine hair loss is relatively light, bone marrow toxicity is heavy. tHP epirubicin hair loss, cardiotoxicity is light. epirubicin in neoadjuvant chemotherapy is more effective in killing tumors when the white blood cells are controlled at the same level if the bone marrow is the evaluation criterion for EPI. The cardiotoxicity is not visible in the short term, so it is not easy to evaluate, but it seems that in the long term, epirubicin is lighter because the dose of epirubicin is generally small, taking into account the bone marrow toxicity. Is it bad to say that the bone marrow toxicity is heavier? A: The toxic side effects of chemotherapy are a concern for every patient, and while affecting whether treatment goes smoothly, they can also place a heavy psychological burden on patients and families. Therefore, there is a need to have various concerns and doubts about the choice of chemotherapy drugs. The following is a description of several important issues: 1. For breast cancer, chemotherapy is an effective treatment that can improve the cure rate and prolong life; 2. The choice of chemotherapy regimen needs to be considered first whether it is effective, i.e. the regimen should be effective or have the highest efficiency. Some chemotherapeutic drugs such as vincristine, which has no significant inhibitory effect on bone marrow, can be used to treat breast cancer? The answer is no, because its efficiency is low and not suitable for use; 3. It is necessary to know that each chemotherapeutic drug has toxic side effects, but their toxic manifestations may differ. For example, adriamycin has significant toxicity to the heart, paclitaxel has allergic reactions, and cyclophosphamide can cause pulmonary fibrosis and hemorrhagic cystitis. Therefore, the choice of program is to consider the patient’s physical condition and other diseases at the same time to avoid causing serious adverse reactions; 4. The choice of similar drugs. As the above patient raised the issue of choosing adriamycin drugs, which is actually better for pirarubicin and epirubicin. For the same kind of drugs, generally the new generation of drugs may be better than the older generation of drugs in terms of efficacy and toxicity on the contrary. For example, pirarubicin and epirubicin are both newer drugs developed on the basis of adriamycin, which has the advantage of less cardiotoxicity. The difference between the two in terms of hair loss and myelosuppression is not significant; 5. The doses of similar drugs cannot be replaced equally because of their different conformations, i.e., 100 mg of pirarubicin is not equal to 100 mg of epirubicin. The calculation must be done according to the body surface area; 6. If serious adverse reactions occur during treatment, prompt consultation and timely adjustment of the regimen are required. Through timely management and preventive treatment, the majority of patients can now tolerate well the side effects of chemotherapy toxicity.