Small bumps inside the breast may be benign or malignant for the following reasons: 1. Breast hyperplasia and breast fibroids are benign lesions, the causes of these diseases are clear, the unstable hormone levels in the body caused by staying up late and irregular life, the female performance is closely related to the menstrual cycle, men may also suffer from this disease, the small bumps are smooth, the activity is still possible, the border is clear. 2. Breast cancer, not related to The bumps are hard and inactive to touch, with adhesions to the surrounding tissues and unclear borders. 3. Lymph node inflammation, bumps on the border of the breast may be lymph node inflammation, if they are small, the inflammation will disappear and be eliminated, if they are large, they need to be removed surgically.