It is customary to refer to smaller masses as nodules, which can occur in any area. Smaller breast masses may be referred to as “breast nodules”. Many women find breast nodules by ultrasound or specialist physical examination, such as breast ultrasound depicting hypoechoic nodules, substantial nodules, etc. Even some women who focus on self-examination are often able to touch hard nodules in their breasts during self-examination, so they are at a loss and come to the clinic with nervousness. So what exactly are breast nodules? In fact, breast nodules are morphological changes in breast tissue, an ambiguous diagnostic term or a clinical manifestation. In other words, a breast “nodule” is a symptom, not a diagnosis of a disease (i.e., the name of the disease). Many breast lesions can appear as “nodules”. These include: breast hyperplasia, breast fibroadenoma, plasma cell mastitis, breast cancer, etc. Due to the high incidence of breast cancer and the fact that one of the symptoms of breast cancer is the discovery of nodules in the breast, patients are often frightened when the word “nodules” is mentioned. Different breast diseases have their own characteristics, and when diagnosing the disease, breast nodules are only one of the diagnostic bases, in addition to the presence of pain, nipple discharge, etc. In addition, we need to know whether the patient has pain, nipple discharge, etc., and we need to combine them with ancillary tests such as ultrasound, mammogram, smear, fine needle aspiration cytology, and even pathological biopsy histology to make a definite diagnosis, and some “nodules” often have morphological differences, so there will be some differences in the doctor’s touch during palpation. The following is a brief introduction to “nodules” in common clinical breast diseases: Mastocytosis is currently the most prevalent breast disease, and its clinical manifestations are pain in the breast, nipple overflow and nodules palpable in the breast. Most patients with mastocytosis can also have multiple hypoechoic nodules detected during ultrasound examination. The nodules are often palpable in both breasts, and in many patients they are more obvious before menstruation and are accompanied by breast pain, while after menstruation, with the relief of pain, the texture of the nodules can become very soft or even disappear. These “nodules” can be lumpy, granular, or hard to the touch, and can be single or many, making patients very worried. Of course, this worry is not unreasonable, because there is a correlation between mastopexy and breast cancer. The pain may be less severe, or even painless. At this point, it is very important to clarify the nature of the “nodule” and consider fine needle aspiration for cytological diagnosis, or direct surgical biopsy and histological diagnosis by freezing to rule out breast cancer. Fibroadenoma of the breast is a benign tumor of the breast, mostly seen in young women. Its clinical presentation is often a “nodule” in the breast. These nodules are usually single, but some patients have multiple nodules. A typical fibroadenoma looks like a glass bullet to the touch, very mobile and naked, while others are located deep in the breast tissue, covered by the upper breast tissue or are smaller and therefore not very clear to the touch. In other patients, it is more confusing to touch and unclear to diagnose because of the presence of more serious mastopathy at the same time. At this time, one can refer to ultrasound and mammogram, which can usually find substantial, intact masses with an intact envelope. Because of the unique efficacy of Chinese herbal medicine on hyperplasia of the breast, after oral herbal intervention, the “nodules” of hyperplasia of the breast can be softened to some extent, but the fibroadenoma remains unchanged, so that it can be more clearly palpated. Plasmacytic mastitis is a chemical inflammatory condition of the breast in which the inflammatory cells are predominantly plasma cells. It can occur in women of any age after puberty, most patients have nipple indentation, and it is often clinically divided into the overflow phase, mass phase, abscess phase, and fistula phase. When the lesion is in the mass stage, a nodule can often be felt under the areola or develop in one place, and can be more than 10 cm in size. These nodules are often hard and tough, with poorly defined borders and adhesions to the skin. Soon, the nodules begin to become red and swollen, with pain, and expand in size, gradually becoming septic and breaking down to form a fistula. In some cases, the nodules can last for 3-5 years without redness, swelling, and pus. If you encounter this situation, the nodules are mainly located in the areola, and there is nipple indentation and previous nipple overflow, then you should consider the possibility of plasmacytoid mastitis. Breast cancer is a malignant tumor of the breast. Patients often come to the clinic with the discovery of nodules in the breast, which, often without pain, may already be of a certain size by the time they are discovered. Most of them are solid, hard and even stone like to the touch. There are also malignant tumor types that can be softer or even cystic because they are rich in cells. Compared to benign tumors, malignant tumors are less mobile. It should be noted that the smaller the nodule, the less obvious the above features are, and sometimes it is difficult to distinguish it from benign nodules. For malignant tumors, pathological examination is the gold standard. It is better to pay attention than to ignore. Therefore, women should pay attention to self-examination of the breast. If breast nodules are found during self-examination, don’t be afraid to go to the hospital, where a specialist will ask about the symptoms, perform a specialized physical examination, and then combine the necessary tests to make a comprehensive analysis and decide on a treatment plan. It should be noted that for non-tumor lesions of the breast, Chinese herbal medicine is more effective, while for tumor lesions, it is less effective than the former and needs to be combined with surgery.