August 31, 2006 — Facial skin resurfacing used to treat precancerous skin lesions could have another advantage and may reduce the risk of skin cancer, researchers say. "Patients who happen to be getting cosmetic treatment may be receiving an added benefit," senior author Susan Swetter, MD, from the Stanford University Medical Center in California, told Medscape.
Reporting in the August issue of the Archives of Dermatology, Dr. Swetter and her team present the findings of their randomized prospective 5-year trial. Looking at patients with previous nonmelanoma skin cancer and severe sun damage, the group studied the effect of facial resurfacing for the treatment of actinic keratoses and prophylaxis against new primary basal- and squamous-cell carcinomas.
The investigators looked at 34 patients from dermatology and otolaryngology clinics at a California-based Veterans Affairs hospital. A total of 7 eligible patients declined study-related treatment, and 5 of these subjects were used as controls. The team randomized 27 patients to 3 treatment groups, which included facial skin resurfacing with lasers, an acid peel, or a topical cream.
Actinic Keratoses Decreased Significantly in All Treatment Groups
After 3 months, the number of actinic keratoses had decreased significantly in all 3 treatment groups — 92% in the laser group, 89% in the acid group, and 83% in the fluorouracil-cream group. None of the participants experienced adverse effects from treatment.
The investigators found treatment with carbon dioxide laser, trichloroacetic acid, or fluorouracil resulted in a lower incidence of nonmelanoma skin cancer compared with the control group ( P < .001). Treatment also resulted in a trend toward longer time to development of new skin cancer compared with control subjects ( P = .07). However, the researchers observed no significant differences among the treatment groups.
"Long-term skin cancer and actinic keratoses surveillance continue to be important, and repeated resurfacing procedures or courses of topical agents, such as fluorouracil or imiquimod, may be necessary," the researchers write. "A larger study comparing trichloroacetic acid resurfacing for actinic keratoses reductionand nonmelanoma skin cancer prophylaxis would help validate the superiority of this resurfacing technique over the carbon dioxide laser and assess its cost-effectiveness compared with photodynamic therapy or imiquimod treatment." They cite improved patient compliance in the trichloroacetic -acid group, ease of performance in the outpatient setting, and subjective measures of better tolerance as reasons this procedure is an attractive alternative to repeated courses with topical agents or laser resurfacing.
Variability in Posttreatment Tretinoin and Sunscreen Use
During an interview with Medscape, Dr. Swetter noted a few key limitations to the study. She pointed to the small sample and the potential for bias because patients in the control group were not randomized. In their paper, the team explains that 12% of the patients in the treatment group did not have a history of nonmelanoma skin cancer compared with the control group, in which all of the patients had
this history and may have been at increased risk. "Despite these limitations, the reductions observed in nonmelanoma skin cancer development suggest efficacyin skin cancer prevention for each of the treatments," the group writes.
Dr. Swetter also explained that an estimated 50% of patients in the study population had difficulty complying with the recommended tretinoin regimen. Several patients cited irritation as thereason for noncompliance, some said they forgot to apply the medication, and others claimed that the pharmacy would not fill theprescription.
Dr. Swetter said that all the patients in the treatment groups as well as controls were asked to use sunscreen daily. And again, many failed to do so. "They gave a variety of reasons," she said, "but in general, treated patients were more compliant with sunscreen use than tretinoin use."
Although the variability in compliance with posttreatment tretinoin and sunscreen use is another limitation of the study, the researchers report, "We do not believe that any significant difference in posttreatment regimen adherence existed among the 3 study arms or biased our results for actinic keratoses reduction or nonmelanoma skin cancer development."
Arch Dermatol. 2006;142:976-982.