The most accurate way to determine the benign or malignant nature of subcutaneous lumps or nodules is to conduct pathological examination, followed by combining with local symptoms and other auxiliary judgment. Common clinical diseases that cause localized masses or nodules include rheumatoid nodules in the joints, lipomas, sebaceous cysts and other benign diseases, as well as malignant lesions such as cutaneous lymphomas and basal cell carcinomas. If a clear distinction between benign and malignant is needed, it is usually necessary to take a biopsy by surgery or puncture for histologic and pathologic examination. In addition to pathologic examination, preliminary diagnosis can also be made based on medical history and symptoms. For example, rheumatoid nodules in the joints are usually accompanied by a history of rheumatoid disease as well as stiffness, swelling, and pain in the joints, and the nodules usually do not increase in size over a short period of time. The appearance of subcutaneous lumps or nodules, it is recommended to go to the hospital for timely consultation.