Seven or eight nodules on one side of the breast may be caused by hairy cysts, multiple fibroids, breast cancer and other disease factors. 1. Multiple cysts: multiple cysts can be caused by hormonal changes, inflammatory stimulation and breast milk accumulation, etc. Multiple fluid-filled cystic masses may appear, which may be round or oval like nodules, and usually have no discomfort, and acute inflammation may appear when secondary infection occurs. 2. Multiple fibromas: Multiple fibromas are benign tumors of the breast, usually without obvious clinical symptoms, and may appear as multiple regular round-like lumps with clear boundaries and good mobility. 3. Breast cancer: Breast lump is the most common symptom in early stage of breast cancer, which is usually a single hard lump with irregular boundary, less smooth surface and not easy to be pushed, and in a few cases, the lumps can be multiple, which need to be identified. When there are seven or eight nodules on one side of the breast, one should consult a doctor in time, and under the guidance of specialists, actively carry out appropriate treatment, which will help to alleviate the discomfort as soon as possible.