Non-Melanoma Skin Cancer
Skin cancer is the most common form of cancer seen in the country. About 1 million people are diagnosed annually. The most common form of skin cancer is basal cell carcinoma followed by squamous cell carcinoma. Skin cancers are most common in fair-skinned older patients. However, with increasing UV exposure and ozone layer depletion, patients are being diagnosed at a much younger age. Previous therapy with x-rays (for facial acne), genetic predisposition, immunosuppression, and arsenic exposure (even 30-40 years prior) increase the risk for non-melanoma skin cancer as well. Basal cell carcinoma (BCC) is slow growing but can be locally invasive if not removed early on. These lesions usually appear as pearly, pink bumps on sun-exposed areas. BCC is asymptomatic, but bleeding with minimal trauma may be the first sign. Squamous cell carcinoma (SCC) usually arises from pre-cancerous lesions called actinic keratoses. These lesions appear as crusted or scaly patches with a red, inflamed base on sun-exposed parts of the skin. SCC is also seen more commonly in organ transplant patients, areas previously treated with radiation, and in previously traumatized skin. SCC can spread more easily to other parts of the body and should be treated as soon as possible. Both BCC and SCC are diagnosed by skin biopsy and treated with Mohs micrographic surgery (when lesions appear on the head and neck) or surgical excision (when lesions are small and on the body). Mohs surgery allows the surgeon to take a sampling of skin and view it under the microscope to ensure that all of the tumor has been removed. Newer topical treatments or photodynamic therapy can occasionally be used in very superficial skin cancers.
Malignant melanoma is the most serious type of skin cancer. In recent decades, the number of people diagnosed with melanoma has increased. It occurs when pigment cells in the skin called melanocytes are exposed to the sun’s ultraviolet (UV) radiation. If the skin receives too much ultraviolet light, the melanocytes may begin to grow abnormally and can become cancerous. Other risk factors include fair skin, first-degree relatives with melanoma, history of one or more severe sunburns, a weak immune system and exposure to certain carcinogens. If melanoma has a chance to grow deep in the skin, it has a higher chance of spreading to other parts of the body than other types of cancer. The first sign of melanoma is often a change in the size, shape, or color of a mole, but malignant melanoma can also appear on the body as a new mole. Abnormal moles can appear anywhere on the body. That’s why it is important to always examine your skin to check for new moles or changes in moles with the help of a partner or mirror. In men, melanoma often shows up on the back, head or neck. In women, melanoma often shows up on the lower legs. Moles that change in color or in texture, take on an uneven shape, get larger, or become bigger should be evaluated immediately.
Early detection is an important goal in melanoma management. If a melanoma is diagnosed early, treatment consists of surgical excision and can be curative. Melanomas diagnosed later are more difficult to treat and require more invasive diagnostic techniques including sentinel lymph node biopsy. Beyond excision, treatments for more advanced melanomas can include radiation therapy, chemotherapy and immune therapies.