At this point, the cancer is a dangerous malignancy, because it has the ability to invade other tissues and metastasize. It arises very rapidly, is the most aggressive of all four types of melanoma, and, unfortunately, is also the second most widespread variety. Unlike the superficial spreading variant, which tends to spread outward, the nodular melanoma grows rapidly upward and inward. NM usually develops in unblemished skin rather than in a nevus. It is often in a fully invasive stage of growth when it is diagnosed.
NM usually develops in middle-aged people.
It feels very round, and the borders are smooth and regular. These lesions often are mistaken for blood vessel abnormalities because of their berry color and texture. This form of melanoma appears on palms, soles, or on nails. The lesion is usually brown or black, multicolored with irregular borders, and flat or nodular. This type of melanoma is aggressive and is usually advanced at diagnosis.