Final answer:
A malignant tumor of flesh tissue is a cancerous growth called a malignant neoplasm and can spread to other body parts, with melanoma being a specific type related to skin cancer.
Step-by-step explanation:
A malignant (cancerous) tumor of flesh tissue is referred to medically as a malignant neoplasm. This kind of tumor is characterized by uncontrollable cell growth, the ability to invade and damage neighboring tissues, and the potential to metastasize, which means the cancer cells can spread to other parts of the body through the lymph system or bloodstream and form new tumors. One specific type of malignant tumor that forms from pigment-producing cells in the epidermis is melanoma, which is known for being highly metastatic and the most fatal of all skin cancers.