Back pain three years after breast cancer surgery may not always be due to bone metastasis, but may also be due to other diseases. Bone metastasis may occur three years after breast cancer surgery. Cancer cells may enter the vein or blood circulation through lymphatic pathway and have distant metastasis, which may be manifested as bone metastasis. Therefore, the possibility of bone metastasis cannot be ruled out when waist pain occurs three years after breast cancer surgery, and patients need to consult the doctor in time and complete relevant examinations to determine whether bone metastasis occurs. Not all back pain three years after breast cancer surgery is bone metastasis, if the patient has kidney stone or lumbar spine disease, such as lumbar disc herniation, lumbar spine fracture, etc., which will lead to lumbar spine nerves compression, and back pain will also occur. If you have back pain three years after breast cancer surgery, it is recommended that you consult a doctor in a timely manner, complete the relevant examinations, clarify the causative factors, and follow the doctor’s instructions for symptomatic treatment.