Other Skin Cancers

Skin cancer is the growth of abnormal skin cells, which form a mass known as a cancerous lesion or tumor. Most cases of skin cancer affect the skin cells of the epidermis, the body’s outermost layer of skin. These cases can be identified as one of the three most common types:

  • Basal cell carcinoma
  • Melanoma
  • Squamous cell carcinoma.

Other skin cancer types are rare and some affect skin cells other than those of the epidermis.

Merkel Cell Carcinoma

Also called neuroendocrine carcinoma of the skin, Merkel cell carcinoma affects Merkel cells, which are usually located within the lowest level of the epidermis. The causes of Merkel cell carcinoma aren’t known, but long-term exposure to the sun, a weak immune system and light-colored skin can be contributing factors. It occurs most often in older people as a bluish-red or flesh-colored bump on the skin of the head, neck or face. It grows and spreads quickly, so early detection and treatment are important.

Sebaceous Gland Carcinoma

The sebaceous glands are located in the skin’s dermal layer and their function is to produce the skin oil that prevents the skin from drying out. Sebaceous gland carcinoma is a growth of cancerous cells that begins in the cells of the sebaceous glands. Lesions are usually hard nodules, and they often appear on the eyelid.

Kaposi Sarcoma

Kaposi sarcoma is a cancer affecting the cells that line the vessels that carry blood and lymphatic fluid. Kaposi sarcoma lesions appear on the skin as purple-red to brown blotches or spots. Symptoms depend on the area affected and vary from no symptoms at all to pain or internal bleeding. Many cases of Kaposi sarcoma occur with AIDS. Other forms of Kaposi sarcoma are common in Mediterranean and African ethnic groups.

Cutaneous Lymphoma

Cutaneous lymphoma is a cancer of the lymphocytes, the body’s immune cells. Primary cutaneous lymphomas are cancers of the lymph cells that originate in the skin, as opposed to cancers that begin elsewhere and spread to the skin. Some types of cutaneous lymphoma affect the body’s T-cells or B-cells. Mycosis fungoides is the most common form of cutaneous lymphoma. It affects T-cells, and appears as a patchy, scaly lesion on the skin.


Keratoacanthoma is, in fact, a benign skin growth. It appears as a fast-growing bump with a rough center. Like skin cancer, it’s caused by sun exposure. Though it’s benign, it can be difficult to differentiate from malignant squamous cell carcinoma, so it’s often treated in much the same way as skin cancer.


American Cancer Society. (2009). What is lymphoma of the skin? Retrieved June 21, 2010, from http://www.cancer.org/Cancer/LymphomaoftheSkin/DetailedGuide/lymphoma-of-the-skin-what-is-lymphoma-of-the-skin

American Cancer Society. (2009). What is kaposi sarcoma? Retrieved June 21, 2010, from http://www.cancer.org/Cancer/KaposiSarcoma/DetailedGuide/kaposi-sarcoma-what-is-kaposi-sarcoma

American Osteopathic College of Dermatology. (2010). Keratoacanthoma. Retrieved June 21, 2010, from http://www.aocd.org/skin/dermatologic_diseases/keratoacanthoma.html

DermNet New Zealand. (2010). Cutaneous t-cell lymphoma. Retrieved June 21, 2010, from http://dermnetnz.org/dermal-infiltrative/cutaneous-t-cell-lymphoma.html

Mayo Clinic. (2008). Merkel cell carcinoma. Retrieved June 21, 2010, from http://www.mayoclinic.com/health/merkel-cell-carcinoma/DS00802

Mayo Clinic. (2010). Retrieved June 17, 2010, from http://www.mayoclinic.com/health/skin-cancer/DS00190