Nodules appearing after radiotherapy for breast cancer may be recurrence of breast cancer or nodules caused by other diseases. 1. Breast cancer recurrence: Breast cancer belongs to one of the common malignant tumors, and the treatment usually adopts surgery, radiotherapy and other methods for comprehensive treatment. If there is no nodule after breast cancer surgery, and the nodule appears after a period of time or after radiotherapy, it may be the recurrence of breast cancer. At this time, the nodule is hard, the border with the surrounding is unclear, and it is difficult to push. 2. Other diseases: the appearance of nodules may also be benign nodules caused by fibroadenoma and other diseases, which often have clear boundaries and are easy to push. Nodules appearing after radiotherapy for breast cancer need to improve relevant examinations to make a clear diagnosis, including pathology examination, ultrasound, tumor marker, tumor gene examination, etc. The condition cannot be understood only by the appearance of symptoms, but should be analyzed according to the results of the examination and clinical symptoms. Nodules after radiotherapy should be treated under the guidance of physician, so as to avoid delaying the condition.