ATLANTA Pretreatment preparation is key to uniform application and a good outcome with the Cook body peel, Dr. Sue Ellen Cox said at the joint annual meeting of the American Society for Dermatologic Surgery and the American College of Mohs Micrographic Surgery and Cutaneous Oncology.
Patients should be pretreated with a retinoid, such as Tazorac (tazarotene), and an alpha hydroxy acid product, such as Lac-Hydrin. "You want the skin to turn over in advance of the procedure, but then you want to stop that about a week before the peel so that there is no irritation at the time of the peel," said Dr. Cox, a dermatologic surgeon in Chapel Hill, N.C.
Just before the peel, one should rub the skin with acetone to degrease the treatment area, then apply a "fairly uniform" thin layer of 70% glycolic acid gel, she advised. A gel formulation is important, because it serves as a partial barrier to the trichloracetic acid (TCA) that is also used as part of the Cook body peel. Too thick a layer of glycolic acid gel will prevent penetration of the TCA, she noted.
Typically, a 40% TCA concentration is applied over the glycolic acid gel. Dr. Cox said she gets the best results with 40% TCA but will try 35% first in those with very thin skin to gauge the development of the characteristic speckled white appearance that serves as the treatment end point.
The peel is stopped at this end point with a 10% sodium bicarbonate solution.
Immediately after the peel, the skin should be hydrated with Aquaphor or Vaseline, and the patient should apply a moisturizer such as Vanicream at home for long-term hydration.
Patients should be advised to use sun protection and to avoid rubbing or otherwise traumatizing the skin in the weeks after the peel, Dr. Cox said.
Skin flaking can occur for 24 weeks depending on the area treated. Hands, for example, will flake for about 2 weeks; legs will flake for about 4 weeks. Most patients will see about a 50% improvement after the first peel. Peels can be repeated every 14 months as necessary, but most patients are satisfied with the initial outcome, she said.
The Cook body peel is a safe, highly predictable peel that can be used almost anywhere on the body. Indications for this peel include actinic keratoses, lentigines, poikiloderma, hyperpigmentation, fine lines, and wrinkles. "Disseminated superficial actinic porokeratosis [DSAP] is my favorite indication; this is where I get all my referrals from my general dermatology friends," Dr. Cox said.
DSAP is very difficult to treat with other modalities, but it responds nicely to the Cook body peel, she said, noting, however, that multiple peels may be necessary in patients with this disease. The peel can be repeated every 24 months as needed in patients with DSAP. The lesions tend to recur, so even after achieving desired results, the peel may need to be repeated in about 2 years, she added.
This patient is shown at baseline and at 7.5 months post treatment, after receiving two Cook body peels. Photos courtesy Dr. Sue Ellen Cox
