Moles suddenly become hard and swollen may be melanoma, and the treatment modes include surgery, physical therapy, immunotherapy and so on. 1. Surgery: Melanoma patients can directly remove the lesion through surgery, which can effectively cure the disease. 2. Physical therapy: for patients who cannot tolerate surgery or cannot undergo a second surgery, they can also choose radiation therapy, which can effectively control the spread of the disease with the use of radiation-assisted treatment. 3. Immunotherapy: For patients with advanced melanoma, the survival time can also be prolonged by injecting antibodies such as PD-1 and IL-2. For patients whose moles suddenly become hard and swollen, it is recommended to go to regular hospitals for consultation and standardized treatment under doctors’ guidance.