Prevent Skin Cancers

Ads

The UAB Comprehensive Cancer Center is leading a national research study of a drug that may aid in the repair of sun-damaged skin and in turn prevent the development of skin cancer among organ transplant patients. Cancer Center Senior ''Scientist and Dermatology Chair Craig Elmets, M.D., is the principal investigator.

The drug dimericine, commonly referred to as "morning-after ' cream," is being tested in people who have had kidney transplants. Like most transplant patients, kidney transplant patients take immunosuppressant medication to prevent the transplant from being rejected.

Because the immune system is diminished, these patients are at an increased risk of developing skin cancer, says Dr. Elmets, who estimates that 40% of these patients will develop some form of the disease.

"While the immunosuppressant medications are beneficial in preventing rejection of the kidney by the body, the downside is that they impair the immune system's response to identify mutant cells in the skin and eradicate those cells before they develop into skin cancer," he says.

While sunscreen is probably the most popular and effective way of protecting the skin from the sun's UV rays, it is only protective when applied prior to sun exposure. After DNA is damaged, there is nothing that sunscreen can do.

The novel aspect of the morning-after cream is that it is able to identify and repair the damage after it has occurred. Patients simply apply the cream once a day onto any areas of the skin exposed to the sun. The cream is safe to be used on the face and has not been shown to cause any side effects in previous studies.

This study is being conducted at UAB, Emory University and the Universities of Pennsylvania, Michigan and California-San Francisco. Dr. Elmets hopes to enroll 100 UAB patients who have had a history of cancer or precancer of the skin. Researchers are mainly interested in the cream's effect on the non-melanoma skin cancers, squamous cell carcinoma and basal cell carcinoma.

"These are the most common types of malignancies in humans, and in the United States alone there will be 1.3 million new basal cell and squamous cell carcinomas developed this year.

That's equivalent to the incidence of all other tumors combined," Dr. Elmets says.

Dr. Elmets hopes the morning-after cream, if proven effective, will eventually be used by a larger population. "Ultimately we hope that we will have evidence from the study that will be applicable to the general population."

Topical Steroids

Topical steroids are effective in inflammatory dermatoses, such as eczema and psoriasis. They are of no value in urticaria or pruritus and will exacerbate rosacea and acne. Eczema (dermatitis) is either endogenous or exogenous in origin. In both types there is a lymphocytic infiltrate in the dermis causing the release of inflammatory mediators which leads to dermal and epidermal oedema and spongiosis. This is manifested by pruritic vesicles which will leak serum and eventually dry up to crack and dry the skin. Secondary bacterial infection may occur and enhance the inflammatory events and worsen the eczema. Corticosteroids act by preventing phospholipid release from the cell membrane and thus prevent their conversion via arachidonic acid into prostaglandins and other mediators of inflammation. Topical steroids are also used in other dermatoses eg keloid scars, alopecia areata and non-infected granulomas. They reduce inflammation and profoundly affect collagen metabolism. The risk of side effects runs parallel with the strength of the steroid, the duration of therapy and, to some extent, the degree of occlusion. The face, genitals and intertriginous areas will absorb more steroids than other areas. Cutaneous side effects may be apparent within two weeks use. The potent and very potent steroids should be carefully monitored and limited to a few weeks use, after which a milder steroid should be substituted if possible. Patients should be reviewed every 3 months. Only mildly and moderately potent steroids should be used in children to avoid potential growth retardation and long lasting cosmetic disfiguration.

If allergic contact dermatitis develops patients should be switched to another steroid in the same potency group. Antibacterial agents can be combined with steroid preparations with good effect. However, the antibiotic can act as an allergen in some eczematous patients. With aminoglycosides there is a risk of ototoxicity and nephrotoxicity so they should not be applied to large areas, or to the external auditory canal in patients with perforated ear drum.

Topical Steroids

C/I: Use on acne (including rosacea), perioral dermatitis, scabies, leg ulcers, tuberculous, ringworm or viral skin disease. Untreated fungal or bacterial infections. Extensive or prolonged use in pregnancy. Continuous prophylaxis.

S/P: Limit use in children or on face to max. 5 days. In infants, napkins and plastic pants may act as occlusive. Monitor use in psoriasis. Withdraw gradually after prolonged use.

ADR: Cushingoid changes and adrenal suppression. Skin atrophy, striae and telangiectasia. Velus hair growth, exacerbation of infections. Hypersensitivity reactions and contact dermatitis; withdraw.

Similar of Prevent Skin Cancers