Actinic keratosis (AK), or solar keratosis, is a common skin growth representing the earliest stage in the development of skin cancer. Actinic keratoses result from chronic sun exposure and as a result develop over the sun exposed areas of the face, ears, lips, scalp, neck, chest, hands, arms, and legs. AKs typically present as superficial scaling, rough, white to brown dry bumps or growths and may be small or large. AKs have a sand-paper like roughness and may be more easily noticed by touch. Actinic keratoses commonly disappear for weeks but return in the same place at a later time. If picked off, they grow back. Involvement of the lower lip commonly presents with chronic dryness, scaling, and cracking. Untreated actinic keratoses may progress to become squamous cell carcinoma and thus are considered pre-cancerous growths. Early detection and treatment is essential to prevent this progression.
Learn more about Actinic Keratosis
Basal Cell Carcinoma
Basal cell carcinoma (BCC) represents the most common type of skin cancer in the world. BCCs develop from exposure to damaging ultraviolet sunlight and tanning beds. As a result, BCCs are most commonly found over sun-exposed areas of the head, neck, chest, back, arms, and legs. Basal cell carcinoma present as round, dome-shaped or flat scaling bumps. BCCs are often pink to red, pearly or translucent and may have rolled borders and visible superficial blood vessels. Basal cell carcinoma can appear as a sore that ulcerates, oozes, and bleeds. They appear to heal on their own but inevitably will recur. BCCs are slow growing and rarely metastasize. However, if untreated they may invade local structures such as fat, muscle, and bone deep to the skin's surface and cause functional or cosmetic impairment. The appropriate treatment depends on multiple factors including the location, size, type of BCC, and histological features.
Squamous Cell Carcinoma
Squamous Cell Carcinoma (SCC) represents the 2nd most common type of skin cancer in the world and develops from the cumulative exposure to ultraviolet sunlight and tanning beds. Squamous cell carcinoma often arise from pre-existing actinic keratoses and may present as rough, crusted or scaling growths over a red, inflamed base. Like BCCS, squamous cell carcinoma may present as open sores that ooze, bleed, and do not heal. SCCs may also ulcerated or present as flat white patches on the lips or inside the mouth. While the most common location for SCCs are the sun exposed areas of the body they may be found anywhere. Squamous Cell Carcinomas are slow growing and like Basal Cell Carcinoma, they may become locally destructive if untreated and invade fat, muscle, cartilage, and bone. Metastasis is rare with SCCs but may occur in higher risk cases. Squamous Cell Carcinoma is responsible for approximately 2500 deaths per year in the United States. Risk factors for more aggressive SCCs include large and deep tumors, involvement of nerves, location on the ears and lips, and on immunosuppressed patients. The appropriate treatment depends on multiple factors including the location, size, type of SCC, and histological features.
Malignant melanoma represents cancer of the melanocytes, the pigment producing cells in our skin. Risk factors for the development of melanoma include ultraviolet sunlight, tanning beds, fair skin, a tendency to tan poorly and burn easily, history of severe sunburns, atypical moles, many moles, and a family history of melanoma. Anyone can develop melanoma but the presence of the above risk factors increases the likelihood. Melanoma represents one of the most aggressive forms of skin cancer with the potential to metastasize to vital organs in the body. Therefore close monitoring for the development of abnormal moles is essential. Melanoma can arise on normal skin or from an already existing mole and can take on a variety of shapes, colors, and sizes. When monitoring for atypical moles and growths, the ABCDEs of Melanoma may be used as a helpful guide to identify worrisome growths.
- A-symmetry: 2 sides of the mole are of different sizes and shapes
- B-order Irregularity: Borders are scalloped, irregular, notched, or hard to find
- C-olor variation: Multiple colors (black, brown, red, white, blue) within the same growth
- D-iameter: Larger than 6mm (size of pencil eraser)- although melanoma CAN be smaller
- E-volution: Any growth that evolves or changes rapidly in size, shape, color
The treatment for malignant melanoma depends primarily on the depth of tumor invasion. For Melanoma in Situ (melanoma confined to the uppermost layer of the skin), simple surgical excision with appropriate tumor free margins is nearly 100% curative. As the tumor penetrates deeper however, surgical excision requires larger tumor free margins and the survival rate begins to fall. Untreated melanoma may penetrate into the blood vessels or lymphatics and metastasize, or spread beyond its origin. Metastatic melanoma tends to travel to local lymph nodes before traveling elsewhere. A procedure known as a sentinel lymph node biopsy may be performed to identify the primary node or group of nodes to which a melanoma has traveled to. Subsequent removal of nodes from this region may prevent the melanoma from traveling farther. The decision to perform a sentinel lymph node biopsy depends on a number of factors including depth of tumor invasion and it's likelihood of spreading. For melanoma that has spread, other treatment modalities may be used such as radiation, chemotherapy, and immunotherapy. The division of dermatology works closely with the medical and surgical oncologists in the UCLA Melanoma Program for cases of malignant melanoma penetrating deeper in the skin.
Other Non-Melanoma Skin Cancers
Basal Cell Carcinoma and Squamous Cell Carcinoma together represent approximately 96% of all non-melanoma skin cancer. Additional, more rare cutaneous tumors include:
- Merkel Cell Carcinoma
- Tumors of the adnexal structures (hair follicles, sebaceous glands, sweat glands)
- Kaposi's Sarcoma
- Cutaneous lymphoma
Soft tissue sarcomas