Abstract: 【Abstract】 Objective To evaluate the efficacy of hematoporphyrin monomethyl ether-mediated photodynamic therapy （HMME-PDT） in the treatment of adult patients with port-wine stains （PWS） in China, and to analyze factors influencing the efficacy. Methods A retrospective study was conducted on the data from 265 adult patients with PWS who underwent HMME-PDT at the Department of Dermatology, West China Hospital, Sichuan University from February 2017 to October 2023. Patients were intravenously injected with hemoporfin at doses of 5 - 6.5 mg/kg, followed by irradiation with a 532-nm green light-emitting diode at the energy density of 100 - 130 J/cm2 （power density, 85 - 100 mW/cm2） for 19 - 25 minutes. Treatments were conducted every 2 - 6 months. The treatment response in the treated area was observed after each treatment, and the clinical efficacy was assessed at least two months after the last treatment. Chi-square test was used to analyze the differences in efficacy between groups. Results Among the 265 adult patients with PWS, the male to female ratio was 90∶175, the patients' age ranged from 18 to 56 years （26.48 ± 6.88 years）, and they underwent 1 to 8 treatment sessions （2.67 ± 1.33 sessions）. After treatment, 102 （38.4%） patients achieved complete remission, 74 （27.9%） achieved marked improvement, 59 （22.2%） had moderate improvement, and 30 （11.3%） showed no response, resulting in an overall response rate of 88.7%. Among 146 patients without hypertrophic lesions, 69 （47.3%） achieved complete remission, with a response rate of 92.5%; among 102 with slightly thickened lesions, 32 （31.4%） achieved complete remission, with a response rate of 87.3%; among 17 with markedly thickened lesions, only 1 achieved complete remission, and 11 achieved marked improvement. Among 50 patients who received more than 3 treatment sessions, 28 （56%） had complete remission, with a response rate of 100%; among 45 who received only one session of treatment, 5 （11.1%） achieved complete remission, with a response rate of 68.9%. Among 232 patients without soft tissue hyperplasia, 95 （40.9%） achieved complete remission, with a response rate of 88.8%; among 33 with soft tissue hyperplasia, 7 （21.2%） achieved complete remission, with a response rate of 87.9%. The therapeutic effects significantly differed among patients with different lesion thicknesses, among those with different treatment sessions, as well as between patients with soft tissue hyperplasia and those without （all P < 0.05）. There were no significant differences in the therapeutic effect among patients of different genders, different ages, with different lesion colors, as well as between patients with nodules and those without, and between patients with treatment history and those without （all P > 0.05）. During and after the treatment, patients experienced varying degrees of swelling, burning sensation, pain, and itching, all of which could be relieved by common treatment; scars occurred in 10 （3.8%） patients, and were managed by symptomatic treatment; no systemic adverse reactions, such as drug allergies or impairment of liver and kidney function, were observed during the treatment. Conclusions HMME-PDT is safe and effective in the treatment of adult patient with PWS. The therapeutic effect of HMME-PDT was associated with lesion thickening and soft tissue hyperplasia, and increased with the increase in treatment sessions.

Key words: Port-wine stain, Hematoporphyrin photoradiation, Hemoporfin, Photodynamic therapy, Adults, Treatment outcome, Influential factors