A dose-finding study for hemoporfin in photodynamic therapy for port-wine stain: A multicenter randomized double-blind phase IIb trial

The effect of autophagy on hemoporfin-mediated photodynamic therapy in human umbilical vein endothelial cells

SIGNIFICANCE

Hemoporfin-mediated photodynamic therapy (HMME-PDT) has been recognized as a safe and effective treatment for port wine stain (PWS). However, some patients show limited improvement even after multiple treatments. Herein, we aim to explore the effect of autophagy on HMME-PDT in human umbilical vein endothelial cells (HUVECs), so as to provide theoretical basis and treatment strategies to enhance clinical effectiveness.

METHODS

Establish the in vitro HMME-PDT system by HUVECs. Apoptosis and necrosis were identified by Annexin Ⅴ-FITC/PI flow cytometry, and autophagy flux was detected by monitoring RFP-GFP-LC3 under the fluorescence microscope. Hydroxychloroquine and rapamycin were employed in the mechanism study. Specifically, the certain genes and proteins were qualified by qPCR and Western Blot, respectively. The cytotoxicity was measured by CCK-8, VEGF-A secretion was determined by ELISA, and the tube formation of HUVECs was observed by angiogenesis assay.

RESULTS

In vitro experiments revealed that autophagy and apoptosis coexisted in HUVECs treated by HMME-PDT. Apoptosis was dominant in early stage, while autophagy gradually increased in the middle and late stage. AMPK, AKT and mTOR participated in the regulation of autophagy induced by HMME-PDT, in which AMPK was positive regulation, while AKT and mTOR were negative regulation. Hydroxychloroquine could not inhibit HMME-PDT-induced autophagy, but capable of blocking the fusion of autophagosomes with lysosome. Rapamycin might cooperate with HMME-PDT to enhance autophagy in HUVECs, leading to increased cytotoxicity, reduced VEGF-A secretion, and weakened angiogenesis ability.

CONCLUSIONS

Both autophagy and apoptosis contribute to HMME-PDT-induced HUVECs death. Pretreatment of HUVECs with rapamycin to induce autophagy might enhance the photodynamic killing effect of HMME-PDT on HUVECs. The combination of Rapamycin and HMME-PDT is expected to further improve the clinical efficacy.

Current clinical evidence is insufficient to support HMME-PDT as the first choice of treatment for young children with port wine birthmarks

BACKGROUND

Port wine birthmark (PWB) is a congenital vascular malformation of the skin. Pulsed dye laser (PDL) is the "gold standard" for the treatment of PWB globally. Hematoporphyrin monomethyl ether (HMME or hemoporfin)-mediated photodynamic therapy (HMME-PDT) has emerged as the first choice for PWB treatment, particularly for young children, in many major hospitals in China during the past several decades.

AIM

To evaluate whether HMME-PDT is superior to PDL by comparing the clinical efficacies of both modalities.

METHOD

PubMed records were searched for all relevant studies of PWB treatment using PDL (1988-2023) or HMME-PDT (2007-2023). Patient characteristics and clinical efficacies were extracted. Studies with a quartile percentage clearance or similar scale were included. A mean color clearance index (CI) per study was calculated and compared among groups. An overall CI (C0), with data weighted by cohort size, was used to evaluate the final efficacy for each modality.

RESULT

A total of 18 HMME-PDT studies with 3910 patients in China were eligible for inclusion in this analysis. Similarly, 40 PDL studies with 5094 patients from nine different countries were eligible for inclusion in this analysis. Over 58% of patients in the HMME-PDT studies were minors (<18 years old). A significant portion (21.3%) were young children (<3 years old). Similarly, 33.2% of patients in the PDL studies were minors. A small proportion (9.3%) was young children. The overall clearance rates for PDL were slightly, but not significantly, higher than those for HMME-PDT in cohorts with patients of all ages (C0, 0.54 vs. 0.48, p = 0.733), subpopulations with only minors (C0, 0.54 vs. 0.46, p = 0.714), and young children (C0, 0.67 vs. 0.50, p = 0.081). Regrettably, there was a lack of long-term data on follow-up evaluations for efficacy and impact of HMME-PDT on young children in general, and central nervous system development in particular, because their blood-brain barriers have a greater permeability as compared to adults.

CONCLUSION

PDL shows overall albeit insignificantly higher clearance rates than HMME-PDT in patients of all ages; particularly statistical significance is nearly achieved in young children. Collectively, current evidence is insufficient to support HMME-PDT as the first choice of treatment of PWBs in young children given: (1) overall inferior efficacy as compared to PDL; (2) risk of off-target exposure to meningeal vasculature during the procedure; (3) administration of steriods for mitigation of side effects; -and (4) lack of long-term data on the potential impact of HMME on central nervous system development in young children.

Efficacy of hemoporfin-PDT on port-wine stains: A retrospective analysis of 2952 cases

OBJECTIVE

To conduct a retrospective analysis of Hemoporfin photodynamic therapy (HMME-PDT) in the treatment of port-wine stains (PWS).

METHOD

A retrospective analysis was conducted based on the clinical data from March 2017 to December 2022, so as to summarize the demographic characteristics, clinical efficacy and adverse reactions. The effectiveness of HMME-PDT was examined with respect to treatment times, age, gender, subtype, and location of PWS lesions.

RESULT

The age of the 2952 cases ranged from 8 months to 56 years old (median, 2.8 years), with 1419 males (48.07 %), and 1533 females (51.93 %). There were 669 cases of pink type (22.66 %), 2184 cases of purplish red type (73.98 %), and 99 cases of nodular thickening type (3.35 %). The prevalence location was face (88.04 %), neck (14.94 %), limbs and trunk. 1602 cases (54.27 %) had never received treatment, 661 cases (22.39 %) had been treated by pulse dye laser (PDL), 229 cases (7.76 %) had previously been treated by PDT, 296 cases (10.03 %) had received both the modalities. The 2952 cases completed totally 7996 HMME-PDT times. Cure rate and effective rate increased continuously with the number of treatments. The pink type has the highest cure rate and effective rate, followed by the purplish red type and the last was the nodular thickening type. The therapeutic effects are considerably influenced by age, subtype, and treatment site (P < 0.05). However, there was no significant difference in the effectiveness of HMME-PDT between both genders. The local adverse reactions after the first treatment included edema (97.73 %), itching (82.62 %), purpura-like change (79.51 %), crusts (24.59 %), infection (4.07 %), scars (1.08 %), hyperpigmentation (0.61 %), and depigmentation (0.41 %). Nausea and vomiting occurred in 2 juveniles and 1 young adult (5, 6 and 22 years old respectively) immediately after treatment, and did not interfere with the administration of the treatment. Patients aged 21-30 were found to have a 3.4-fold higher likelihood of undergoing HMME-PDT under general anesthesia compared to those aged 15 or younger. There was no distinct systemic adverse reaction, such as allergic responses, cardiovascular effects, neurological symptoms, hematological abnormalities, respiratory symptoms, or musculoskeletal issues.

CONCLUSION

HMME-PDT is preferred in treating PWS, with relatively high effective rate and cure rate, mild local reactions and no distinct systemic adverse reaction.

Analysis of related factors affecting hemoporfin-mediated photodynamic therapy for port-wine stain: A retrospective study

BACKGROUND

Hemoporfin-mediated photodynamic therapy (HMME-PDT) is currently considered one of the most promising therapies for port-wine stain (PWS). However, the efficacy of this is very variable and needs further studies.

METHODS

A total of 101 patients with PWS in the face, neck, or extremities who received at least 2 HMME-PDT sessions were included in the study, and correlations of efficacy with age, gender, locations, treatment sessions, and PDL treatment history were analyzed.

RESULTS

The efficacy of HMME-PDT in patients with different ages, locations, and different numbers of prior PDL treatment showed constantly significant differences after 1/2/last session (p < .05). The number of treatments was associated with efficacy, and patients who received more than two sessions had a better response than those who underwent two sessions only (p < .001). Ordinal logistic regression analysis confirmed the above-mentioned associations. Nevertheless, patients of different sex, subtype, and lesion size showed no significant differences.

CONCLUSIONS

Our studies demonstrated that HMME-PDT is effective in the treatment of PWS. The more prior PDL treatments, older age, lips involvement, PWS on limbs were adverse factors for Hemoporfin-PDT, while multiple HMME-PDT sessions can improve effective and response rate. Besides, ambient temperature and lesions temperature should be concerned, local cooling provides some relief from pain but may influence effect.

Clinical efficacy and safety of two different hematoporphyrin monomethyl ether-mediated photodynamic therapy regimen in Chinese children with port-wine stain

Hematoporphyrin monomethyl ether-photodynamic therapy (HMME-PDT) has achieved encouraging clinical outcomes in adult port-wine stain (PWS). Optimal treatment option for children with PWS was minimal. To compare whether the clinical effectiveness of HMME-PDT with the 5-min (fast) administration treatment regimen (FATR) was better than the 20-min (slow) administration treatment regimen (SATR) for PWS of children in vivo and in vitro. Thirty-four children with PWS were divided into two groups including FATR and SATR. The two groups received three times HMME-PDT, respectively. Treatment efficacy and safety were evaluated in vivo and in vitro. Erythema index (EI) was used to evaluate the clinical outcomes. Both FATR and SATR were effective and safe in children with PWS after HMME-PDT. There were significance differences between the two groups in reductions of EI after the second treatment (p < 0.001) and the third treatment (p < 0.001) with HMME-PDT. The serum HMME concentration reach the peak level at short time compare with SATR group. A significance increased superoxide levels were observed in FATR group compare to SATR groups in vitro (p < 0.05). Our study suggested that HMME-PDT was effective and safe for children with PWS, the therapy regimen with FATR was better in clinical efficacy than that of the SATR.

Influential Factors in the Efficacy of Hemoporfin-Mediated Photodynamic Therapy for Port-wine Stains

Hemoporfin-mediated photodynamic therapy (HMME-PDT) is commonly used in the treatment of port-wine stains (PWS). However, the influential factors for the efficacy of the treatment are not well defined. This study intends to observe the influential factors for the efficacy of HMME-PDT in the treatment of port-wine stains (PWS). A total of 551 patients with PWS of head and neck was enrolled in this retrospective study. Further screening the patients of facial PWS, 484 patients were chosen. Patients were treated with HMME-PDT. All patients received 1~3 sessions of treatment with 2~3-month intervals. We photographed the lesions before each session and 2~3 months after the last session. Ages, sessions, lesion subtypes, and previous treatment history were related to the response of HMME-PDT (P =0.032, P<0.001, P=0.012, P=0.003 respectively). Treatment sessions were the independent factor correlated with efficacy after 3 sessions of treatment. Patients with no treatment history targeting PWS showed higher efficacy than those were treated with laser or other photodynamic treatment (P<0.05). The efficacy was higher by increasing the sessions of treatment. The efficacy was higher for lesion on maxillary prominence area and mandibular prominence area that on frontonasal prominence area and optic vesicle area (P<0.05). HMME-PDT is an effective in the treatment of PWS. Patients received no previous treatment for PWS, total treatment sessions and lesion on maxillary prominence area and mandibular prominence area are positive factors.

Efficacy of photodynamic therapy in the treatment of port wine stains: A systematic review and meta-analysis

Background

Port wine stains (PWS) often cause cosmetic effects and psychological distress. Pulsed dye lasers (PDL) and photodynamic therapy (PDT) are the most commonly used treatments. PDL is still the "gold standard" of therapy to date. However, its shortcomings have become apparent as clinical applications have increased. PDT has been proven as an alternative to PDL. Patients with PWS still lack enough evidence about PDT to make informed treatment decisions.

Objective

The purpose of this systematic review and meta-analysis was to assess the safety and effectiveness of PDT for PWS.

Methods

The online datasets, comprising PubMed, Embase, Web of Science, and the Cochrane Library, were searched for meta-analysis-relevant publications. Two reviewers separately evaluated the risk of bias in each listed study. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the treatment and safety outcomes.

Results

Our search retrieved 740 hits and only 26 studies were finally included. Among the 26 studies included, 3 were randomized clinical trials, and 23 were prospective or retrospective cohort investigations. Based on a gathered assessment, the percentage of individuals achieving a 60% improvement was estimated to be 51.5% [95% confidence interval (CI): 38.7-64.1; I ² = 83.8%] and a ≥75% improvement was 20.5% (95% CI: 14.5-26.5; I ² = 78.2%) after 1-8.2 treatment sessions (GRADE score: very low). Due to the statistical diversity of the meta-analysis, a subgroup assessment was performed to determine the sources of diversity. The collected findings indicated that the impact of PDT on enhancing the medical effectiveness of PWS was significant in different treatment sessions, different types of ages, different locations of PWS, and different types of PWS. Pain and edema occurred in most patients. Hyperpigmentation was present in 7.9-34.1% of the patients in 17 studies. Photosensitive dermatitis, hypopigmentation, blister, and scar were infrequently reported, with 0-5.8% incidences.

Conclusion

Photodynamic therapy is recommended as a safe and effective treatment for PWS based on the current evidence. However, our findings are based on poor-quality evidence. Therefore, comparative investigations of a large scale and high quality are necessary to support this conclusion.

Hematoporphyrin Monomethyl Ether Photodynamic Therapy of Port Wine Stain: Narrative Review

Port wine stain (PWS) is a congenital and progressive capillary malformation characterized by structural abnormalities of intradermal capillaries and postcapillary venules. The visible manifestation is often considered a disfigurement and the accompanying social stigma often causes serious emotional and physical impact. Hematoporphyrin monomethyl ether (HMME) is a newly authorized photosensitizer for treating PWS in China. Hematoporphyrin monomethyl ether photodynamic therapy (HMME-PDT) has successfully treated thousands of Chinese patients with PWS since 2017, and HMME-PDT may be one of the most promising strategies for the treatment of PWS. However, there are few reviews published about the clinical use of HMME-PDT. So in this article, we want to briefly review the mechanism, efficacy evaluation, effectiveness and influencing factors, and the common postoperative reactions and treatment suggestions of HMME-PDT in the treatment of PWS.

The Efficacy of Hematoporphyrin Monomethyl Ether Photodynamic Therapy in Adult Patients with Port-Wine Stains: A Retrospective Study

Introduction

Hematoporphyrin monomethyl ether-photodynamic therapy (HMME-PDT) has been showing promising results in the treatment of port-wine stains (PWSs). We evaluated the clinical efficacy and treatment response of HMME-PDT in adult Chinese patients with PWSs.

Methods

A single-center retrospective study recruited adult PWS patients with negative HMME skin test results from December 2017 to May 2020. Patients received an intravenous injection of 5 mg/kg HMME and the lesions were exposed to 532 nm LED green light with an irradiation power density of 85–95 mW/cm² for 20–25 min. Digital photographs were taken before and after two therapy sessions and observed by three blinded dermatologists for clinical response.

Results

A total of 72 patients aged between 18 and 55 years were recruited. There were 65 patients of the flat purple type, 5 of the hypertrophic type, and 2 of the nodular thickening type. Of the 65 patients, 7 showed excellent efficacy (10.77%), 13 patients indicated good efficacy (20.00%), 47 patients showed fair efficacy (64.62%), while 3 cases displayed no improvement (4.62%). All five patients of the purple and hypertrophic type showed fair efficacy (100%), and no improvement was observed in patients of the nodular thickening type (100%). Pain, pruritus, and a burning sensation were observed during treatment. Edema was noted on the treated areas post-treatment. No other obvious systemic adverse reactions were observed.

Conclusion

HMME-PDT is an effective and safe treatment for adult patients with purple PWSs. Multiple HMME-PDT treatments can improve the response and cure rate.

Comparing HMME-PDT and Cynergy dual-wavelength laser in the treatment of facial PWS

BACKGROUND

Pulsed dye laser (PDL) is the gold-standard therapy for port-wine stains (PWSs), but the therapeutic efficacies vary widely with each individual. Recent studies suggest that hematoporphyrin monomethyl ether-photodynamic therapy (HMME-PDT) is an effective alternative in the treatment of PWS. This retrospective study aimed to compare the effects of HMME-PDT and Cynergy dual-wavelength laser on red and purple color types of PWS METHODS: This retrospective study included 38 PWS patients who received Cynergy dual-wavelength laser treatment (PDL group) and 39 PWS patients who received HMME-PDT treatment (HMME-PDT group). Patients in each group received two treatments. The curative effect of purple or red PWS in two groups was analyzed.

RESULTS

After the first treatment, the total significant response rate and the total response rate of the HMME-PDT group were 43.59% and 74.36%, which were significantly higher than those of the PDL group (5.26% and 47.36%) (P < 0.05). After the second treatment, the total significant response rate and the total response rate of the HMME-PDT group were 69.23% and 100%, which were obviously higher than those of the PDL group (34.21% and 68.42%) (P < 0.05). For both groups, the total significant response rate of purple-type PWS was remarkably higher than that of red-type PWS (the HMME-PDT group: P = 0.004; the PDL group: P = 0.048). There was no obvious difference in terms of patient age and PWS location between the HMME-PDT and PDL groups. Furthermore, there was no considerable difference in the incidence of adverse reactions between the two groups (P > 0.05).

CONCLUSION

The single-center retrospective study suggested that HMME-PDT might have better efficacies on purple and red PWS than PDL treatment. The total treatment efficacy was greater in purple-type PWS than in red-type PWS.

From Basic Mechanisms to Clinical Research: Photodynamic Therapy Applications in Head and Neck Malignancies and Vascular Anomalies

Head and neck cancers are largely squamous cell carcinomas derived from the epithelial lining of the structures in the region, and are often classified anatomically into oral, oropharyngeal, nasopharyngeal and laryngeal carcinomas. The region’s component structures serve complex and intricate functions, such as speaking, swallowing and breathing, which are often compromised by these neoplasms. Such lesions may also cause disfigurement, leading to distressing social and psychological issues. Conventional treatments of these neoplasms usually involve surgical intervention with or without chemoradiotherapy. These have shown to be efficacious; however, they can also cause damage to healthy as well as diseased tissue, exacerbating the aforementioned problems. Access to a given region to deliver the treatments is also often a problem, due to the complex anatomical structures involved. The use of photodynamic therapy in the head and neck region has been established for about two decades. In this review, we looked at the basic mechanisms of this intervention, examined its use in common head and neck malignancies and vascular anomalies, and reported on the most recent clinical studies. We further included a clinical guide which can help replicate the use of this technology by any unit. Based on this review, photodynamic therapy has been shown to be efficacious in the treatment of head and neck malignancies and vascular tumours. This therapy can be targeted to the diseased tissue and causes no damage to underlying structures. Recent studies have shown this therapy to be as effective as conventional therapies, without causing major adverse effects.

Consensus Statement for the Management and Treatment of Port-Wine Birthmarks in Sturge-Weber Syndrome

Importance

Sturge-Weber syndrome (SWS) is a neurocutaneous syndrome involving the skin, brain, and eyes. Consensus recommendations for management are lacking.

Objective

To consolidate the current literature with expert opinion to make recommendations that will guide treatment and referral for patients with port-wine birthmarks (PWBs).

Evidence Review

In this consensus statement, 12 nationally peer-recognized experts in dermatology with experience treating patients with SWS were assembled. Key topics and questions were formulated for each group and included risk stratification, optimum treatment strategies, and recommendations regarding light-based therapies. A systematic PubMed search was performed of English-language articles published between December 1, 2008, and December 1, 2018, as well as other pertinent studies identified by the expert panel. Clinical practice guidelines were recommended.

Findings

Treatment of PWBs is indicated to minimize the psychosocial impact and diminish nodularity and potentially tissue hypertrophy. Better outcomes may be attained if treatments are started at an earlier age. In the US, pulsed dye laser is the standard for all PWBs regardless of the lesion size, location, or color. When performed by experienced physicians, laser treatment can be safe for patients of all ages. The choice of using general anesthesia in young patients is a complex decision that must be considered on a case-by-case basis.

Conclusions and Relevance

These recommendations are intended to help guide clinical practice and decision-making for patients with SWS and those with isolated PWBs and may improve patient outcomes.

Crosstalk between oxidative stress, autophagy and apoptosis in hemoporfin photodynamic therapy treated human umbilical vein endothelial cells

BACKGROUND

Photodynamic therapy (PDT) provides a treatment for port-wine stain (PWS) using hemoporfin (hematoporphyrin monomethyl ether, HMME), a novel photosensitizer, reporting better efficacy and lower recurrence rate. This study investigated the effects of HMME-PDT on human umbilical vein endothelial cells (HUVECs) as well as underlying mechanisms.

METHODS

Cell proliferation ability was measured by CCK8 assay and cell apoptosis was determined by TUNEL assay and Western blot analysis. Confocal fluorescence microscopy monitoring RFP-GFP-LC3 transfected HUVECs and Western blot analysis were used to evaluate autophagy. 3-Methyladenine (3-MA), Z-VAD-FMK, N-acetylcysteine (NAC) were used for inhibitor studies.

RESULTS

HMME-PDT decreased cell proliferation ability in an HMME concentration and light dose-dependent manner. Oxidative stress played an important role in HMME-PDT induced cell apoptosis and autophagy in HUVECs. Pretreatment with Z-VAD-FMK, the inhibitor of apoptosis, enhanced HMME-PDT induced autophagy. 3-MA, the suppressor of autophagy, significantly increased HMME-PDT induced apoptosis rates.

CONCLUSIONS

Our study demonstrated that HMME-PDT induced both apoptosis and autophagy in HUVECs via oxidative stress. Our data suggested that HMME-PDT- induced autophagy was able to prevent apoptotic cell death of HUVECs and rendered them more resistant to HMME-PDT induced toxicity.

Clinical outcome measures and scoring systems used in prospective studies of port wine stains: A systematic review

BACKGROUND

Valid and reliable outcome measures are needed to determine and compare treatment results of port wine stain (PWS) studies. Besides, uniformity in outcome measures is crucial to enable inter-study comparisons and meta-analyses. This study aimed to assess the heterogeneity in reported PWS outcome measures by mapping the (clinical) outcome measures currently used in prospective PWS studies.

METHODS

OVID MEDLINE, OVID Embase, and CENTRAL were searched for prospective PWS studies published from 2005 to May 2020. Interventional studies with a clinical efficacy assessment were included. Two reviewers independently evaluated methodological quality using a modified Downs and Black checklist.

RESULTS

In total, 85 studies comprising 3,310 patients were included in which 94 clinician/observer-reported clinical efficacy assessments had been performed using 46 different scoring systems. Eighty-one- studies employed a global assessment of PWS appearance/improvement, of which -82% was expressed as percentage improvement and categorized in 26 different scoring systems. A wide variety of other global and multi-item scoring systems was identified. As a result of outcome heterogeneity and insufficient data reporting, only 44% of studies could be directly compared. A minority of studies included patient-reported or objective outcomes. Thirteen studies of good quality were found.

CONCLUSION

Clinical PWS outcomes are highly heterogeneous, which hampers study comparisons and meta-analyses. Consensus-based development of a core outcome-set would benefit future research and clinical practice, especially considering the lack of high-quality trials.

Hematoporphyrin monomethyl ether photodynamic therapy for the treatment of facial port-wine stains resistant to pulsed dye laser

BACKGROUND

Pulsed dye laser is the first treatment choice for port-wine stains. However, as some facial port-wine stains are resistant to this modality, we evaluated the efficacy and safety of hematoporphyrin monomethyl ether (hemoporfin) photodynamic therapy for the treatment of such resistant port-wine stains.

METHODS

Patients were treated with two sessions of hemoporfin photodynamic therapy in our department. Patients received an intravenous injection of hematoporphyrin monomethyl ether (5 mg/kg) followed by 532 nm LED green light therapy. Three physicians graded the improvement in the port-wine stain, using a 4-level scale. Patients' satisfaction, reaction to treatment, and adverse effects were evaluated.

RESULTS

Thirty-one patients (mean age, 23.9 ± 11.9 years, range, 3-48 years) were enrolled in this study. Hypertrophic lesions accounted for 48.4% of port-wine stain, with 80.6% of lesions being larger than 40 cm². With regard to location, 41.9% were located on the central face and 32.3% involved a mix of the central and peripheral face. After one session, a treatment response was identified in 87.1% of cases, with the response deemed 'significant' in 29.0%. After two sessions, these rates increased to 100.0% and 61.3%, respectively. The clinical effect after two sessions was significantly greater than that after one session. Treatment reactions and adverse effects were well tolerated, and included pruritus, burning sensation, pain, edema, purpura-like change, blister, crust, and hyperpigmentation.

CONCLUSIONS

Hemoporfin photodynamic therapy is a promising treatment for port-wine stains resistant to pulsed dye laser therapy.

Photodynamic therapy for port-wine stains in extremities: Report of 4 cases

OBJECTIVES

To observe the clinical efficacy of photodynamic therapy mediated by hemoporfin (HMME-PDT) for port-wine stains (PWS) on extremities and explore its possible influencing factors.

METHODS

Four patients with PWS in extremities were treated by HMME-PDT, and patients with negative results in the skin test were given an intravenous injection of 5 mg/kg of HMME. The patients were irradiated with 532 nm LED green light, and immediately applied cold compress after treatment. These patients were informed to stay away from light for two weeks. A follow-up every 2 weeks was conducted with treatment for 2 or 3 times in total. After the end of treatment, a follow-up was carried out for 6-12 months and the efficacy and safety were evaluated.

RESULT

Three of the four patients were considered cured, and the treatment was ineffective for one patient. During the follow-up observation, all patients had different degrees of edema, and there were no signs of chromatosis or scarring.

CONCLUSION

PDT treatment for patients with extremity PWS demonstrate high efficiency and safety, without obvious adverse reactions and recurrence.

Retrospective study of photodynamic therapy for pulsed dye laser-resistant port-wine stains

Pulsed dye laser-resistant port-wine stains present a therapeutic challenge. The aim of this study was to evaluate the efficacy and safety of photodynamic therapy for treating these lesions. A total of 67 patients with pulsed dye laser-resistant cervicofacial port-wine stains were retrospectively assessed after undergoing photodynamic therapy mediated with a combination of hemoporfin and 532-nm light. For objective evaluation of photodynamic therapy efficacy, first, the colorimetric changes in the port-wine stain lesions were evaluated according to the L*a*b* color coordinate system, then the values of color changes (ΔE) and blanching rate were calculated. For subjective evaluation of improvement, photographs taken before and after photodynamic therapy were evaluated by three independent assessors blindly. Patient satisfaction was also used as a factor in the subjective evaluation. Adverse events were recorded after treatment. The median ΔE decreased significantly from the pretreatment value of 13.42 to 9.90 at the 2-month follow up (P < 0.001). The median blanching rate of port-wine stains was 28.04% after an average of 1.21 sessions of photodynamic therapy. Based on the overall visual assessment, 46.2% patients showed excellent or good levels of improvement (>50% color blanching). Adverse events were minimal, transient and self-limiting. In conclusion, photodynamic therapy serves as an alternative means to treat pulsed dye laser-resistant port-wine stains.