Which type of skin cancer is most common and characterized by light or pearly nodules?

Basal cell carcinoma is indeed the most common form of skin cancer, primarily arising from the basal cells, which are located in the lower part of the epidermis. This cancer is often characterized by the appearance of light or pearly nodules on the skin. These nodules can sometimes be shiny and may have visible blood vessels. They typically grow slowly and can become more severe if not treated, but they rarely metastasize (spread to other parts of the body).

In contrast to basal cell carcinoma, squamous cell carcinoma, though also common, presents differently and often appears as red, scaly patches or open sores rather than light or pearly nodules. Melanoma is a more aggressive form of skin cancer that arises from melanocytes and can manifest as irregularly shaped moles or spots that may be dark in color, often requiring immediate medical attention. Adenocarcinoma, while a type of cancer that can occur in various glands of the body, is not specifically related to skin cancer and thus does not fit the description provided in the question.