What type of skin cancer appears as firm, irregular papules or nodules on sun-exposed areas?

The description of skin cancer as appearing with firm, irregular papules or nodules on sun-exposed areas aligns with squamous cell carcinoma. This type of cancer is known for developing in the upper layers of the skin, particularly in areas frequently exposed to ultraviolet light, such as the face, ears, neck, and backs of the hands.

Squamous cell carcinoma can manifest as red, crusted, or scaly patches that can progress to firm nodules. This aggressive nature, alongside its potential for metastasis if left untreated, underscores the importance of recognition and early intervention.

In contrast, while melanoma typically arises as dark, irregular moles or spots with shades of brown, black, or tan and can represent a more significant risk when detected late, it doesn’t typically present as firm nodules. Basal cell carcinoma generally appears as a pearly or waxy bump rather than the described irregular papules or nodules. Actinic keratoses are precursors to skin cancer characterized by rough, scaly patches and are often not elevated like nodules.

Understanding these nuances helps in recognizing the specific features and risks associated with different skin cancers, allowing for appropriate assessment and intervention.