Who should consider a melanocyte transplant?
Melanocyte transplantation is NOT first-line therapy for vitiligo. Before attempting transplantation you should have either:
- Tried and failed standard medical therapies for vitiligo including at least a full course of topical steroids and ultraviolet light therapy, or
- Have patches of vitiligo larger than a quarter that contain only depigmented hairs.
As with most surgical procedures, you should be in good physical health for optimal outcome. Your vitiligo MUST be stable. That means that you should not have seen any new or expanding areas of vitiligo for at least one year prior to the procedure. If you have active vitiligo, the chances for a successful transplant are unlikely. You should have relatively small areas of depigmentation to be treated. Large areas are not easily treated and often require several treatments for complete coverage.
You should not have any problem with wound healing or abnormal scar formation such as keloid-type scars. You should not have clinically atypical appearing moles. This treatment requires patience and a long-term time commitment since several procedures may be required. You should expect to establish a collaborative working relationship with your doctor. Note: it is important for you to confirm the diagnosis of vitiligo with a physician familiar with the disorder. Some other conditions are often confused with vitiligo by the general practitioner and are actually very treatable by medical therapies.
What is involved in melanocyte transplantation?
The idea is simple: remove melanocytes from an unaffected portion of skin and transfer the cells to skin that has no melanocytes. Since melanocytes are the cells that give color to the skin, if the transplanted cells survive the procedure, they should soon produce pigment to begin the repigmentation process. There are three steps to the actual procedure:
- Harvesting and preparation of the unaffected tissue
- Preparation of the depigmented site to be transplanted
- Transplantation of the cells onto the depigmented area
Step 1: Donor tissue (i.e.. unaffected tissue to be used as the source of melanocytes may be obtained from inconspicuous areas such as the buttock or scalp. The area to be removed will be injected with an anesthetic to completely numb the area. The injection itself has been likened to a bee sting that lasts about 10 seconds. If skin is to be removed from the buttock, a specialized surgical blade will be used in order to minimize the risk of scarring. It is possible that the donor site will scar and it is likely you will be able to see redness at the site for at least 1 year following the procedure. It usually takes about two weeks for the donor site to heal completely.Step 2: The depigmented area that is to be treated requires preparation for the transplant. Melanocytes reside at the junction between the epidermis and the dermis and for the melanocytes to be able to adhere and begin to grow, the first layer of the skin (the epidermis) must be removed. Again, the area to be treated will be anesthetized so that the entire surface should be numb. It also may be necessary to take oral medications to reduce the pain. The area to be treated will be thoroughly cleansed and the oils of the skin will be removed. An acid commonly used for facial peels (trichloroacetic acid will be applied to the area and the acid will then be neutralized by several ice-cold washes. Following neutralization, the surface of the skin will be removed by a process called dermasanding, which is basically removal of the epidermis with sterile sandpaper. Once the epidermis is removed, the area will be kept moist using saline soaked gauze.
If skin is removed from the back of the scalp, deeper cuts will be made which require suture placement. The sutures will need to be removed in 7-10 days after the procedure. There will be some scarring in the scalp, but it should not be visible since it is under your hair. It may be necessary to shave a portion of your scalp prior to removal of the donor skin. This step of the procedure is similar to the first step of a hair transplant. The tissue will be placed in a special media that contains enzymes that break the skin cells apart. This part of the process takes about 60-90 minutes, after which the skin cells are present as a single-cell suspension. This suspension will ultimately be transplanted onto your depigmented area of skin.
Step 3: Once the tissue is prepared and the transplantation site is ready, the cells may be placed onto the dermasanded skin. The cells will be re suspended in either a collagen gel or a gel called Regranex which contains a growth factor that has been shown to hasten wound healing. The cells will then be evenly applied and held into place with a collagen film and non adherent dressing. An ace bandage will be applied to assure that the dressings remain in place. You will need to keep the treated area as immobilized as possible for the next 24 hours so that the melanocytes will have a chance to "take." You will be seen after 24 hours to check the wound and dressing. Another dressing will be applied which will be left in place for approximately 5-6 days.
Follow-up: The transplantation site will need to be examined again one week after the procedure and sutures should be removed at that time. The site should remain covered until the epidermis has completely regrown. Once that has happened (usually no longer than two weeks), you will be encouraged to get some natural sunlight to the area. After one month you may need to get ultraviolet light treatments to the area. You may see the beginnings of repigmentation as early as 6 weeks after the transplant but the final outcome will not be known for 9-12 months. You should plan to be seen every 6-8 weeks for follow-up within the first 6-9 months after the procedure.
For more information:
Sancy Leachman, M.D.
Huntsman Cancer Institute
University of Utah - Dept. of Dermatology
50 North Medical Dr.
Salt Lake City, Utah 84132