A grade 3 solid breast nodule indicates a mass in the breast with an imaging grade of 3. It is usually benign, with a less than 2% chance of being malignant. Solid breast nodule grade 3 may be breast fibroma, breast hyperplasia, mastitis and other diseases. 1. Breast fibroma: The main symptoms of breast fibroma include painless lumps, rarely accompanied by breast pain and breast discharge. Breast fibroids can be treated by surgical excision under doctor’s advice. 2. Breast hyperplasia: clinically, it mainly manifests as breast swelling and pain, lumps and nodular sensation. It can be treated with Tamoxifen Citrate tablets as prescribed by the doctor, and in serious cases, it can be treated by surgical excision. 3. Mastitis: The main symptoms of mastitis include redness, swelling, pain and fever in the breast. It can be treated with antibiotics or surgical incision and drainage to drain the fluid under doctor’s advice. The 3 categories of solid breast nodules are more likely to be benign, but it is still recommended to visit the hospital and let the doctor guide further treatment.