Skin cancer is one of the common malignant tumors, which includes basal cell carcinoma, squamous cell carcinoma, malignant melanoma, malignant lymphoma, idiopathic hemorrhagic sarcoma (Kaposi sarcoma), eccrine carcinoma, dermatofibrosarcoma protuberans , vascular sarcoma, etc., of which basal cell carcinoma and squamous cell carcinoma of the most common, accounting for about 90% of skin cancer, it is described in this article, "skin cancer" mainly refers to two types of 
Cell carcinoma. 
      Skin cancers occur in the elderly, including basal cell carcinoma more common in patients over 40 years of age, squamous cell carcinoma more common in patients over 50 years of age. Generally 51 ~ 60 age incidence peak, 40 years of age rare, 20 years of age is rare. The disease more men than women, male-female ratio is about 2:1. Around 80% of the exposed parts of the body, such as the head, face, neck, back of the hand and other parts, a few occurred in the non-exposed parts. Such as basal cell carcinoma occur in the face and neck, and many more in the mouth, such as orbit, nose, cheeks, forehead, ears and other parts of the surrounding is also commonly found in back of the hand, forearm and upper back; squamous cell carcinoma more than half of found in head and neck may also occur in the limbs, trunk, head occur in the cheek, scalp, eyelids, forehead, etc., limbs occur in the back of the hand and foot. Palms and soles is generally believed that non-occurrence of basal cell carcinoma and squamous cell carcinoma. 
      The cause of this disease has not yet fully clear, its occurrence may be related to sun exposure, radiation, arsenic, tar derivatives such as long-term stimuli. Burn scar, leukoplakia, chronic ulcers, prolonged unhealed of the fistula, discoid lupus erythematosus, radiation dermatitis and other skin lesions can also be secondary to the disease. However, many patients with no obvious incentive. 
       Chinese literature, the name of non-skin cancer, but the ancient books in the Health and warts on the skin surface, loss of wing, and inverted flower superfluous sore records and so on. Such as "waiting on the various source of the disease," says: "Fan Flower sore persons, born of a rice, breaking the blood out of his head, then the main bad meat, getting a great root, pus out, meat, anti-casual flowery-like." "Yi Zong Jin Jian" Yiyun: "push the non-moving, hard as stone, skin-color as usual, gradually grow up ... ... falling into refractory, shaped gas gradually eclipsed, muscle slim, the more the more hard-ulcer, color is purple, rot steeped, seepage bloody water. ... ... the shape of large open sores inverted flower tumor cards. "These descriptions and quite similar to skin cancer. Ming Xue Li Zhai more words: "those who turn to spend sore from the sore ulcer caused by wind after the anger Xuezao. Or sores, such as pterygium prominent bacteria, different sizes, or out of varying lengths, such as snakeheads. Conquer when Zi liver supplement gas, treated with veratridine paste, pterygium from the entry to be re-designate their strength gradually, sepsis will make the coating to be effective, otherwise, although routed into being undone, if the wrong knife needle loss medicine, moxibustion fire, its potential, or Yi Shen prolonged bleeding, cold and heat-induced vomiting card will be nourishing the spleen and stomach is good. "clinical manifestations of this disease, pathogenesis, governance law was elaborated and put forward the principle of treatment inside and outside the Tung-chih and treatment contraindications. 
  
  The clinical signs and symptoms of skin cancer; 
Basal cell carcinoma and squamous cell carcinoma have a low degree of malignancy, slow growth; easy to find and to facilitate the biopsy features, easily done early diagnosis, early treatment, prognosis is good. 're On their clinical signs as described below. 
      1) basal cell carcinoma generally consists of four types, the most common is the nodular ulcer type. 
      (1) nodular ulcerative type: since the beginning of the epidermal to the emergence of a small pea-sized grain of rice, waxy nodules, texture very hard, the surface of a small number of expansion in the capillaries, slightly out of the skin surface, or just like erythema and does not uplift, or slightly nodular surface of the skin with mild depression down. Nodules can be gradually expanded or new lesions appear, are blended to form a wax-like shiny disc-shaped plaques, the central tend to form brown, brown or dark gray scar on the skin, followed by scab occurred ulcer, gradually expanded to form a round, oval or non-plastic ulcers, the size of that ring or coins ranging from ulcers and rolled up the edge of a solid and often was shaped translucent and rugged, the surrounding skin without inflammation, the bottom of the pearl-like or wax-like appearance, and sometimes damage to the surface completely covered by callus. Ulcer is slow and deep extension to the surrounding, such as rat-bite-like, forming a typical basal cell carcinoma clinical patterns, hence the name for the erosion, ulcer, ulcers can be part of the healing and scarring occurs, but also be extended to subcutaneous tissue and even cartilage and bone. A variety of organizations can be made to destroy deep-shaped. Occurred in the face can damage the nose, ears, eyes and maxillary sinuses and other parts of the cartilage and bone tissue, causing bleeding or intracranial invasion or disfigurement. 
      (2) pigment type: nodules of relatively cheap and shallow, the same damage and nodular ulcerative type. Since contains more pigment, damage to the edge addition to pearl luster, there are points, or reticulate dark brown or dark brown pigment spots, the central part we can see there is pigmentation, exposing susceptible to bleeding scab, scab that may be dark brown or even carbon black particles, and malignant melanoma, similar to the easily misdiagnosed. 
      (3) a hard porphyritic or fibrosis type: common in the head and neck for the hard light yellow or yellow-white patches, slightly elevated, ill-defined, it seems like a hard spot disease can be maintained long-term integrity and ultimately ulceration. 
      (4) superficial type: skin lesions of superficial, mostly occurs on the trunk, showing one or a few pieces infiltrative erythema, scaling, or crusted surface, edge or the entire lesion is slightly elevated, at least part of the edge of a small pearl-like or line-like dike-like. Of this type may eventually fibrosis. Similar to psoriasis, eczema, or seborrheic dermatitis. 
The slow development of basal cell carcinoma of the damage is generally rare occurrence of regional lymph node metastasis nor distant metastasis. 
      2) Squamous cell carcinoma: squamous cell carcinoma of the early clinical manifestations and basal cell carcinoma, no significant difference. Squamous cell carcinoma mostly occurs in long-term abnormal state of the skin, often by keratosis, leukoplakia, or other shift in precancerous conditions. Early skin lesions are mostly a dry rice to soybeans large hard papules or small nodules, the surface Chenganhongse or telangiectasia, rough, closely attached to the central object of horny, easy to strip, forced strip is easy to cause bleeding , then peel will grow horny substances. Can occur after a central ulcer, ulceration are continuously increasing, and its development faster than basal cell carcinoma. In a relatively short period of time, forming a large cancerous ulcer, its edge was significantly higher, the broad and hard, was cauliflower valgus, ulcers uneven bottom, showing the red meat, there is milky white granular or necrotic tissue. Sometimes, the depth of ulcer formation hole, the shape of the volcanic vents. Cancer cells can be outgoing, can be, and deep tissue adhesion, the formation of a broad base of vegetation, appearance like the nipple or food pattern tumor. Infection, there viscous pus, odor abnormal, conscious pain. 
     Squamous cell carcinoma developed rapidly, devastating large, may be stretching connective tissue, cartilage, periosteum and bone, often of regional lymph node metastasis may occur late shift internal organs may occur, particularly in mucosal squamous cell carcinoma is often easier to transfer.