Willey Andrea, Anderson R Rox, Sakamoto Fernanda H
*Andrea Willey, MD, Surgical & Aesthetic Dermatology Sacramento, Sacramento, California; †Department of Dermatology, University of California Davis, Sacramento, California; ‡Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts; §Harvard Medical School, Boston, Massachusetts.
Dermatol Surg. 2015 Nov;41(11):1290-5. doi: 10.1097/DSS.0000000000000512.
The efficacy of photodynamic therapy (PDT) using topical 5-aminolevulinic acid (ALA) for the treatment of actinic keratosis (AK) is lower on the distal extremities compared with head and neck areas. A recent pilot study demonstrated increased efficacy of ALA PDT when the skin is warmed during ALA incubation. Prolonged clearance rates on the heated extremity were noted in 3 subjects that were evaluated after the study ended. The aim of this study was to evaluate the longevity of clearance rates after temperature-modulated PDT for the treatment of AKs on the extremities.
A total of 18 subjects (20 pairs of extremities) with at least 10 AKs on the upper or lower extremities were enrolled in the single-center study. Twenty percent ALA was applied to both extremities and heated during the 1-hour incubation period, followed by exposure to 10 J/cm 417-nm blue light. Lesions were photographed, counted, and templated at baseline, 1 week, and 3, 6, 9, and 12 months after treatment.
A total of 17 subjects completed the 1-year study. The total number of lesions counted at baseline was 724 Grade 1 and 2 AKs (median 15 on each extremity). The lesion count at 3 and 12 months was 70 (9.6%) and 72 (9.9%), respectively. Grade 3 AKs did not resolve with treatment. The median baseline temperature of the treated extremities was 31.6°C. The median maximum temperature during the 1-hour incubation period was 41.2°C. The median clearance at 3 months was 90% and the same was maintained at 12 months. No new AK lesions formed in the treated areas within the 12-month follow-up period.
Warming the skin after application of ALA is well tolerated, does not increase side effects, and increases the long-term efficacy of PDT for the treatment of AKs. The authors suggest that mild skin warming may both improve efficacy and reduce variability of response to PDT in practice.
与头颈部区域相比，使用外用5-氨基酮戊酸（ALA）的光动力疗法（PDT）治疗光化性角化病（AK）在远端肢体上的疗效较低。最近一项试点研究表明，在ALA孵育期间对皮肤进行加热时，ALA PDT的疗效会提高。研究结束后对3名受试者的评估发现，加热肢体的清除率延长。本研究的目的是评估温度调制PDT治疗肢体AKs后清除率的持续时间。
共有18名受试者（20对肢体）在上下肢至少有10个AKs参与了这项单中心研究。将20%的ALA应用于双下肢，并在1小时孵育期内加热，随后暴露于10 J/cm²的417nm蓝光下。在基线、治疗后1周、3、6、9和12个月对病变进行拍照、计数和标记。
共有17名受试者完成了1年的研究。基线时计数的病变总数为724个1级和2级AKs（每肢中位数为15个）。3个月和12个月时的病变计数分别为70个（9.6%）和72个（9.9%）。3级AKs未通过治疗消退。治疗肢体的基线中位数温度为31.6°C。1小时孵育期内的中位数最高温度为41.2°C。3个月时的中位数清除率为90%，12个月时保持不变。在12个月的随访期内，治疗区域未形成新的AK病变。
应用ALA后对皮肤进行加热耐受性良好，不会增加副作用，并提高了PDT治疗AKs的长期疗效。作者建议，在实践中，轻度皮肤加热可能既提高疗效又降低对PDT反应的变异性。
