Recently, 78-year-old Uncle Shi was diagnosed with skin cancer. In fact, the old man’s legs and feet had been broken for 3 years, but he did not pay attention to it until cancer occurred later. Experts say that long-term skin problems should not be underestimated, and it is not rare for “old rotten feet” to develop into skin cancer in outpatient clinics. Uncle Shi lives in Xiangshan. He said that 3 years ago, some itching on the outside of the thigh, scratching broke, and some yellowish liquid oozed out. At that time, look at the skin ulcers on the size of peanuts, he did not care. But after that, the leg is still itchy, the old man will continue to scratch. A year later, the breakout expanded to the size of an egg. A month or so ago, the breakout suddenly got bigger, the size of a child’s hand. He then went to the local hospital. The doctor said that the limb might have to be amputated, and he was transferred to the orthopedic department of the city’s Lee Wai Lee Hospital. He was seen by Dr. Shen, the chief orthopedic surgeon. He said that upon admission, the old man’s leg had a serious rupture, reaching 12 cm in diameter. There were ichthyosiform lesions on the skin, which looked like skin cancer. Subsequent blood tests and pathology slides confirmed this judgment, and the old man was diagnosed with squamous cell carcinoma. Fortunately, the old man’s skin cancer was not highly malignant, the adjacent muscles and bones were not invaded, and the distal liver, gallbladder and lung were not metastasized. He did not need to amputate his limbs, but only needed to remove the diseased tissues and then implant the skin. According to Dr. Shen, the main reason why the old man developed skin cancer is the long-term repeated infections that stimulated and led to the mutation of cells. According to Dr. Mao Wei, chief physician of the Department of Dermatology of Li Huili Hospital, the causes of skin cancer include sun exposure, repeated infections, trauma, long-term consumption of Chinese medicine with excessive arsenic and long-term exposure to some chemical substances. Among them, sun exposure and recurrent infections are the most common ones. Occasionally, there are patients with lower limb ulcers, commonly known as “old rotten feet”, which eventually turn into skin cancer in outpatient clinics. We would like to remind the public that if a skin ulcer does not heal for several months, it is best to go to the hospital. Don’t take it lightly and don’t buy ointment to apply it by yourself. Scars, pigmented moles, etc. should be taken care of carefully and not rubbed frequently with clothes or other objects.