A painless, solitary hard lump in the breast is the clinical characteristic of fibroadenoma of the breast. Breast fibroadenoma is the most common benign breast tumor, which occurs mostly in young women. The lumps are mostly round, with smooth surface, clear demarcation with surrounding tissues and no adhesions, and the possibility of malignant transformation is small, about 1%. Breast tuberculosis is common in middle-aged women, with few systemic symptoms of tuberculosis, mainly manifested as breast lumps, with a slow course. After rupture, ulcers and long-lasting overflow can occur, and discharge of thin pus like bean residue, and the ipsilateral axillary lymph nodes are often significantly enlarged. The following diseases are also causes of painless solitary hard lumps in the breast: 1. Primary breast lymphoma Primary breast lymphomas are rare and have been reported in a variety of histological types. They can originate in the breast or can spread to the breast. 2.Menopausal breast cancer Breast cancer is a serious threat to women of all ages. The incidence of breast cancer increases significantly in postmenopausal women with severe obesity and central fat accumulation, and the use of estrogen after perimenopause can increase the chance of breast cancer. Breast cancer is one of the most common malignant tumors in women, accounting for 7-10% of all malignant tumors in the body and is second only to uterine cancer in women. Its incidence is often associated with heredity, as well as a higher incidence in women between the ages of 40-60, before and after menopause. It is one of the most common malignant tumors that usually occurs in the glandular epithelial tissue of the breast and seriously affects women’s physical and mental health and even endangers their lives. Breast cancer is rare in men, and only about 1-2% of breast patients are men. Primary malignant lymphoma of breast (PMLB) is a malignant tumor that occurs in the lymphatic tissue of the breast. Primary malignant lymphoma of the breast is very rare and is often part of a generalized lymphosarcoma, probably due to the low amount of lymphoid tissue in the breast tissue. Regarding the origin of breast malignant lymphoma, most scholars believe that the breast is a potential site of mucosa-associated lymphoid tissue and that primary malignant lymphoma of the breast is a mucosa-associated lymphoid tissue tumor (MALT) associated with malignant lymphoid tissue in the periductal and lobular areas of the breast in the form of tumor-like hyperplasia, while others believe that it originates from naïve undifferentiated mesenchymal cells in the vascular ectoderm. The majority of malignant lymphomas in the breast are non-Hodgkin’s malignant lymphomas. Microscopically, malignant lymphomas in the breast have common features of malignant lymphomas in other areas. The tumor cells infiltrate diffusely between the lobules and ducts, but the ducts are not destroyed, and there are no tumor cells or inflammatory exudates in the lumen. Fibrosarcoma of the breast is the most common type of breast sarcoma, second only to lobular cystic sarcoma. It is characterized by the absence of epithelial components in the tumor and consists purely of mesenchymal components.