Department of Dermatology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
J Dermatolog Treat. 2010 Jul;21(4):252-7. doi: 10.3109/09546630903271555.
Since actinic keratoses (AKs) often appear in areas with field cancerization, photodynamic therapy (PDT) may have significant advantages over the standard treatment options.
Clinical efficacy of PDT with topical methyl aminolevulinate (MAL-PDT) in field cancerization was evaluated with respect to the number of AKs and photodamage.
A total of 14 patients with 223 AKs on the face or scalp were treated with MAL-PDT. Two treatments with a 3-monthly interval were given. At baseline, before the second treatment and 3 months after the end of therapy, the number of AKs were counted and photodamage was assessed with respect to skin roughness, hyperpigmentation, hypopigmentation, scarring, atrophy, telangiectasia and wrinkling.
Complete clearance was reached in patients with a moderate degree of actinic damage, whereas a severe degree of field cancerization demonstrated only partial clearance. The global score for photodamage improved significantly. After the follow-up period, none of the patients reaching clearance had developed relapsing or new AKs.
MAL-PDT induces a high clearance rate of AKs, dependent on the degree of field cancerization, with a good improvement in photodamage and prevention of developing new AKs. Thus, more PDT sessions are needed in patients with a severe degree of field cancerization.
由于光化性角化病（AK）通常出现在具有癌前病变的区域，因此光动力疗法（PDT）可能比标准治疗方法具有显著优势。
评估局部氨甲环酸（MAL-PDT）在癌前病变中的 PDT 对 AK 数量和光损伤的临床疗效。
对 14 名面部或头皮上有 223 个 AK 的患者进行 MAL-PDT 治疗。每 3 个月间隔进行两次治疗。在基线、第二次治疗前和治疗结束后 3 个月，计数 AK 的数量，并根据皮肤粗糙度、色素沉着过度、色素减退、瘢痕、萎缩、毛细血管扩张和皱纹评估光损伤。
中度光损伤的患者达到完全清除，而重度癌前病变仅部分清除。光损伤的总体评分显著改善。随访期间，达到清除的患者均未出现复发或新的 AK。
MAL-PDT 可诱导 AK 的高清除率，这取决于癌前病变的程度，同时可显著改善光损伤并预防新的 AK 发生。因此，对于重度癌前病变患者需要更多的 PDT 疗程。
