Final answer:
Warts and moles are benign tumors, which are non-cancerous growths that do not spread to other parts of the body or invade surrounding tissues. Benign tumors can include non-cancerous conditions like moles and warts but require monitoring as they can sometimes develop into more serious conditions like melanoma, which is highly metastatic.
Step-by-step explanation:
Warts and moles are benign tumors of the skin, meaning they do not invade surrounding tissues or metastasize. A benign tumor is a non-cancerous growth that typically does not spread to other parts of the body. It can include a range of conditions from simple moles, which are benign accumulations of melanocytes, to more complex entities like uterine fibroids. While benign skin growths like warts, which are caused by viruses, and moles don't usually become cancerous, they can be removed if they cause discomfort or have the potential for developing into melanoma, which is a much rarer but the most serious type of skin cancer that can metastasize if not treated promptly.
Comparatively, invasive tumors such as basal cell carcinoma, the most common type of skin cancer, or squamous cell carcinoma, which also originates in the epidermis, have a greater potential to invade neighboring tissues. Still, these particular carcinomas rarely metastasize. On the more severe end of the spectrum lies melanoma, a type of skin cancer that significantly differs from benign skin growths due to its aggressive nature and high likelihood to metastasize when not treated in the early stages.