On April 13, our hospital successfully held the official launch meeting of MDT for skin squamous carcinoma and precancerous lesions, which marks the importance and necessity of multidisciplinary collaboration in the diagnosis and treatment of skin squamous carcinoma, as our hospital will insist on collaborative treatment and play the role of MDT to continuously optimize the treatment plan and improve and innovate the treatment methods of skin squamous carcinoma and precancerous skin lesions. In order to help people understand and appreciate squamous skin cancer, this article briefly introduces squamous skin cancer. What is cutaneous squamous carcinoma? Skin squamous carcinoma is a malignant tumor originating from the epidermis or appendages, mostly seen in elderly people over 50 years old, and usually occurs on the head and face. It often occurs on the basis of certain skin precancerous diseases or evolves from various precancerous diseases, and a few of them can be primary. What causes it? Skin squamous carcinoma, like other malignant tumors, has no clear etiology, but is obviously related to the following factors: 1. long-term exposure to ultraviolet light, X-ray or thermal radiation damage; 2. chemical carcinogens: such as occupational exposure to arsenic, polycyclic aromatic hydrocarbons, anthracene, tobacco tar, etc.; 3. viral infection: especially human papilloma virus infection; 4. pre-cancerous skin diseases: such as solar keratosis, mucosal leukoplakia Arsenic keratosis; 5.Cancerous changes on the basis of certain chronic skin diseases: such as chronic ulcer, chronic osteomyelitis, lupus erythematosus, atrophic sclerosing moss, etc.; 6.Long-term use of immunosuppressants after organ transplantation; 7.Hereditary factors: certain hereditary skin diseases such as pigmented dry skin disease, albinism, etc. have significantly higher incidence of skin cancer than the general population. How to diagnose? On the basis of chronic skin diseases, such as scar, chronic ulcer, keratosis, etc., or the appearance of hard nodules or plaques on normal skin with rapid growth, squamous carcinoma should be suspected, and tissue biopsy must be performed to further confirm the diagnosis pathologically. How to treat? Treatment requires comprehensive consideration of tumor stage, location, patient’s age, health condition, economic situation, etc., and specific analysis of each case, some suggestions below can be adopted. Surgery: For small tumor size and well differentiated tumor, surgical resection is preferred, which can remove the tumor more completely and the wound heals quickly, but there may be scars of different sizes after healing. The excised specimen should be examined for pathology to clarify the diagnosis and whether the tumor is clean. Photodynamic therapy: For patients with small tumor size, well differentiated tumor, tumor in head, face or genital area, photodynamic therapy can be chosen. Photodynamic therapy has high cure rate, low recurrence rate and non-invasive, and can maintain the integrity of organs to the maximum extent, but its treatment cost is slightly expensive and pain is obvious during the treatment. Radiotherapy: It is suitable for patients who are old and frail and have contraindications to surgery. Especially for those with large tumor size, poorly differentiated tumor, but not yet invaded bones or metastasis can choose radiation therapy. For patients with distant metastasis, systemic chemotherapy may be required. How to prevent? 1.To break down the factors closely related to the occurrence of squamous skin cancer: 2.Minimize exposure to the sun and take good sun protection measures when going out 3.Minimize exposure to skin cancer-causing chemicals 4.Treat human papilloma virus infection, chronic ulcer, solar keratosis, etc. as early as possible 5.When highly suspected of squamous skin cancer, go to regular hospitals as early as possible and take histopathological biopsy in time 6.When diagnosed with skin squamous skin cancer, it should be treated early to avoid further development of tumor. In conclusion, for squamous skin cancer and any other tumors, we should actively do “three early”: early prevention, early diagnosis and early treatment, that is, we should actively take good protective measures in daily life, and once there are chronic ulcers, solar keratosis and other skin diseases and new rashes above the skin surface with rapid growth, we should go to regular hospitals as early as possible.