A superficial mass is a mass located on the surface of the body that originates from the skin and appendages, subcutaneous and deep soft tissues and is palpable on the surface of the body. Most of the body surface masses are benign diseases, which are divided into two categories: tumorigenic and non-tumorigenic masses. Lipoma 1.Origin: It is a benign tumor caused by the proliferation of well-differentiated adipose tissue. 2.Site: It can occur in all parts of the body, especially in fat-rich parts such as limbs, trunk, shoulders, back, buttocks, etc. It can also occur in the abdominal cavity such as perinephric and retroperitoneum. 3.Characteristics: soft texture, round or lobulated, may have pseudocystic feeling. The boundaries are clear, and there are generally no clinical symptoms such as pain. There is no adhesion with the surrounding area, and the base can be moved. It grows slowly, but can be huge in size, and is rarely malignant. There are single and multiple lipomas. 4.Treatment: There is tenderness. Larger and symptomatic ones can be removed, but usually not one by one. Deep lipomas can become malignant and should be removed in time. Sebaceous cyst (powder tumor) 1.Source: caused by sebaceous gland obstruction. 2, performance: it is found on the back of the head, round, smooth, soft or slightly tense, without fluctuation, adhering to the superficial skin, with a cyst wall, the cyst content is tofu crumb-like, white powdered sebum and broken sebaceous gland cells, a small hole in the center of the swelling is black (the opening of the gland duct) often secondary infection, forming abscesses, breaking, sebum is discharged with pus, with a foul odor. After healing, it can still recur. 3.Nature: benign, rarely cancerous. 4.Treatment: For sebaceous cysts that have been infected, anti-infection treatment should be given first, and when abscesses are formed, sebum and pus should be removed by incision and drainage, and the treatment should be self-healing or second-stage clearing and suturing; for sebaceous cysts without infection, they can be removed completely by surgery. Hemangioma 1.Origin: capillary, vein or arteriovenous mutation. 2.Manifestation: red or greenish-purple elevation under the skin, sometimes visible tortuous vessels or vascular murmur can be heard. 3.Nature: benign. 4.Treatment: Sclerotherapy injection, surgical excision. 1.Source: pigmentation of epidermis and dermis. 2. Performance: Smooth surface, may protrude from the skin, hair growth is visible. 3.Nature: benign, with the possibility of malignant transformation. 4. Treatment: Can be surgically removed. Melanoma 1, performance: rapid growth, irregular, with stinging pain, visible satellite nodules around, can also occur in the nail. 2.Nature: highly malignant. 3, treatment: surgery to expand the excision. Skin papillary warts 1, source: squamous epithelial hyperplasia. 2, performance: papillary prominence, elderly may have hyperpigmentation. 3, nature: benign, there may be malignant change. 4, treatment: sometimes can fall off on their own, suspected of malignant surgery to remove. Neurofibroma 1.Source: at the nerve endings or nerve trunk. 2, performance: mostly asymptomatic, a few with pain, can be multiple. 3.Nature: benign, with the possibility of malignant change. 4.Treatment: surgical excision. Skin cancer 1.Origin: basal cells or squamous cells. 2.Manifestation: Prevalent in head, face and lower limbs, ulcer-like growth, cauliflower-like surface, with bleeding and odor. 3.Nature: low grade malignant, bone marrow metastasis is most common. 4.Treatment: surgery + radiotherapy.