This type of skin cancer is the second most common that we see in dermatologic practices. Many of these lesions arise from actinic keratoses located on sun-exposed skin. Generally, they may appear as eczema, or a crusty, thicker lesion that begins to grow. Occasionally, the change can be dramatic with a rapid growth of a nodular lesion. More commonly, the sun-damage keratosis grows gradually and become a larger.
Metastasis or internal spread is relatively rare from this type of skin cancer, especially when these occur on sun-exposed skin. Exceptions to this spread can be seen with lesions on ears, mucous membranes such as the lips, mouth, and genital areas as well as skin cancers located on sun-protected skin. People at greater risk with occurrence of squamous cell carcinomas and risk of metastasis are those that have organ transplants, or other diseases that compromise their immune system enough that it dysregulates the cells and cancer occurs.