Itchy skin one year after breast cancer surgery is considered to be related to dry skin, mastitis, allergic dermatitis and breast cancer recurrence. 1. Dry skin: one year after breast cancer surgery, patients do not pay attention to skin care, which may lead to excessive dryness of local skin and itchy skin. 2. Mastitis: it is considered to be related to autoimmune factors, bacterial infection and breast trauma. When mastitis occurs one year after breast cancer surgery, it can be manifested as itchy skin, redness, swelling, elevated temperature, etc. It is also easy to have other symptoms such as swelling and pain, localized lymph node swelling, etc. 3. Allergic dermatitis: when the local skin of patients one year after breast cancer surgery comes into contact with allergic substances, it can be manifested as itchy skin. Some patients will also have erythema, papules, oozing, blisters and other conditions. 4. Breast cancer recurrence: recurrence of the disease can also cause itchy skin in some patients one year after surgery, and they are also prone to breast lumps, nipple overflow, enlarged lymph nodes in armpit and other symptoms. It is recommended that patients with itchy skin one year after breast cancer surgery should consult a doctor for examination so as to clarify the cause of the disease and then follow the doctor’s instructions for treatment. Avoid scratching the itchy skin to prevent skin breakage and infection.