Histological Characteristics of Port-Wine Stains with Complete Regression After Photodynamic Therapy Treatment: A 7-Year Follow-Up

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.

Hemoporfin-Mediated Photodynamic Therapy for Port-Wine Stains on Extremities

INTRODUCTION

Pulsed dye laser (PDL) is currently considered to be the first-line treatment for port-wine stains (PWSs) on the extremities despite its less than satisfactory therapeutic efficacy. Hemoporfin-mediated photodynamic therapy (HMME-PDT) is a vascular-targeted therapy that has rarely been used to treat PWSs on the extremities. Here, we evaluate the clinical efficacy and safety of HMME-PDT for the treatment of PWSs on the extremities.

METHODS

Clinical data and dermoscopic images of PWSs on the extremities were obtained from 65 patients who underwent HMME-PDT between February 2019 and December 2022. The clinical efficacy of HMME-PDT was analyzed by comparing the pre- and post-treatment images. The safety of HMME-PDT was evaluated through observation during the treatment period and post-treatment follow-up.

RESULTS

The efficacy rate of a single HMME-PDT session was 63.0% and that of two and three to six sessions was 86.7% and 91.3%, respectively. A positive correlation was found between therapeutic efficacy and the number of HMME-PDT sessions. The therapeutic efficacy of HMME-PDT was better on the proximal extremities than on other parts of the extremities (P = 0.038), and the efficacy of treating PWSs in each site was relatively improved with an increase of treatment time. The clinical efficacy of HMME-PDT differed across four PWS vascular patterns identified by dermoscopy (P = 0.019). However, there was no statistical difference in the therapeutic efficacy based on age, sex, type of PWS, and treatment history (P > 0.05), which may be partly attributed to the relatively small sample size or poor cooperation of infant patients. No obvious adverse reactions were observed during the follow-up period.

CONCLUSIONS

HMME-PDT is a very safe and effective treatment for PWSs on the extremities. Multiple HMME-PDT treatments, lesions located in proximal limbs, and PWSs with type I and IV vascular patterns under dermoscopy were associated with higher efficacy of HMME-PDT. Dermoscopy may help predict the clinical efficacy of HMME-PDT.

TRIAL REGISTRATION NO

2020KJT085.

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.

Pathogenesis of Port-Wine Stains: Directions for Future Therapies

Port-wine stains (PWSs) are congenital vascular malformations that involve the skin and mucosa. To date, the mechanisms underlying the pathogenesis and progression of PWSs are yet to be clearly elucidated. The potential reasons for dilated vessels are as follows: (1) somatic GNAQ (R183Q) mutations that form enlarged capillary malformation-like vessels through angiopoietin-2, (2) decreased perivascular nerve elements, (3) the coexistence of Eph receptor B1 and ephrin B2, and (4) the deficiency of αSMA expression in pericytes. In addition, ERK, c-JNK, P70S6K, AKT, PI3K, and PKC are assumed to be involved in PWS development. Although pulsed-dye laser (PDL) remains the gold standard for treating PWSs, the recurrence rate is high. Topical drugs, including imiquimod, axitinib, and rapamycin, combined with PDL treatments, are expected to alter the recurrence rate and reduce the number of PDL sessions for PWSs. For the deep vascular plexus, photosensitizers or photothermal transduction agents encapsulated by nanocarriers conjugated to surface markers (CD133/CD166/VEGFR-2) possess a promising therapeutic potential in photodynamic therapy or photothermal therapy for PWSs. The pathogenesis, progression, and treatment of PWSs should be extensively investigated.