Skin cancer, the most common type of cancer in the United States as reported by the Skin Cancer Foundation, causes the abnormal and uncontrollable growth of skin cells. Pre-cancer cells are cells that appear abnormal but have not yet formed into tumors. The Centers for Disease Control and Prevention report that unprotected sun exposure causes 65 to 90 percent of skin cancers. Therefore, areas of the skin most exposed to the sun, including the ears, are at an increased risk of developing skin cancer.
Actinic Keratosis
Actinic keratosis, also called solar keratosis, describes a scaly or crusty lesion commonly found on the ears, bald scalp, face, lips or back of the hands. Actinic keratoses begin so small that they remain undetectable to the eye, but the patient can feel a rough patch. Over time the lesion will grow. Some become red while others turn tan or pink. Actinic keratoses indicate the presence of sun damage. Although some remain benign, approximately 40 to 60 percent of squamous cell carcinomas begin as actinic keratosis, according to the Skin Cancer Foundation, making it a pre-cancer.
Bowen's Disease
Bowen's disease, also known as squamous cell carcinoma in situ, describes an early form of squamous cell carcinoma that can occur in areas of the body exposed to sun, such as the ear. The lesions formed in Bowen's disease become larger than those of actinic keratosis, creating red patches that appear scaly or crusty. Bowen's disease only affects cells of the epidermis, or outer skin layer; if it progresses, it becomes squamous cell carcinoma.
Squamous Cell Carcinoma
Squamous cell carcinoma still causes about 20 percent of all skin cancer cases, reports the American Academy of Dermatology. Squamous cell carcinoma typically affects areas of the body most exposed to the sun including, the ears, lower lip, bald scalp, face, neck, hands, arms or legs. Squamous cell carcinoma describes the abnormal growth of the squamous cells---flat keratinocytes found near the outer layer of the epidermis. Squamous cell carcinoma lesions may form red nodules or remain flat, crusty and scaly in appearance.
Basal Cell Carcinoma
Basal cell carcinoma, the most common type of skin cancer, produces lesions that appear pearly white or waxy. Basal cell carcinoma begins in the basal cells---the keratinocyte-producing cells found in the deepest portion of the epidermis. Exposure to the sun causes the abnormality in the basal cells, making the ears vulnerable. Basal cell carcinomas grow slowly, so they are easy to treat; however, the recurrence rate remains high, according to the Mayo Clinic.
Melanoma
Melanoma, the fastest growing and therefore most dangerous type of skin cancer, begins in the melanocytes---the cells in the epidermis that produce the pigment melanin. Melanomas usually appear as black or brown lesions. The ear is especially vulnerable, and melanoma of the ear accounts for 7 to 14 percent of all melanomas, according to the Journal of Family Practice.
