Photodynamic therapy of necrobiosis lipoidica using methyl aminolevulinate: A retrospective follow-up study

Shedding Light on Photodynamic Therapy in the Treatment of Necrobiosis Lipoidica: A Multicenter Real-Life Experience

Necrobiosis Lipoidica (NL) is a dermatological condition characterized by the development of granulomatous inflammation leading to the degeneration of collagen and subsequent formation of yellowish-brown telangiectatic plaques usually localized on the pretibial skin of middle-aged females. Due to its rarity and unclear etiopathogenesis, therapeutic options for NL are not well-standardized. Among them, photodynamic therapy (PDT) is an emerging tool, although its efficacy has primarily been evaluated in single case reports or small case series. This study reports the real-life experience of a cohort of NL patients treated with PDT at the Section of Dermatology of the University Hospital of Messina and Reggio-Emilia. From 2013 to 2023, 17 patients were enrolled -5 males (29%) and 12 females (71%) aged between 16 and 56 years (mean age: 42 ± 13 years), with a median duration of NL of 8 years. The overall complete clearance (>75% lesion reduction) was 29%, while the partial clearance (25-75% lesion reduction) was 59%, with 12% being non-responders. This study adds to the little amount of evidence present in the literature regarding the effectiveness of PDT in the treatment of NL. Variability in treatment responses among patients underscores the need for personalized protocols, optimizing photosensitizers, light sources, and dosimetry. The standardization of treatment protocols and consensus guidelines are essential to ensure reproducibility and comparability across studies.

Treatment options for necrobiosis lipoidica: a systematic review

BACKGROUND

Necrobiosis lipoidica (NL) is a rare, idiopathic, and recalcitrant disease of collagen degeneration for which treatment options have been poorly studied. Due to its recurring nature, risk for ulceration, and high morbidity, there is a need to understand existing treatment modalities to better inform clinical care.

OBJECTIVE

This review aims to describe the therapeutic modalities reported in the literature for the treatment of NL.

METHODS

A literature search of treatments was performed by searching for publications between January 2016 and May 2022 on PubMed and Scopus. Given the limited high-quality evidence, case reports and series were included. Only publications presenting information on both attempted treatments and outcomes were included.

RESULTS

A total of 60 novel articles were identified (54 case reports, two case series, and four retrospective cohort studies). These studies cumulatively reported on 274 patients and covered treatments including phototherapy, topical corticosteroids, topical calcineurin inhibitors, biologics, immunosuppressants, JAK inhibitors, combination therapies, and several others. The greatest amount of evidence was found for photodynamic therapy (improvement in 72 of 80 patients), UVA-based phototherapy (12 of 33), topical corticosteroids (21 of 46), compression therapy (15 of 20), and topical calcineurin inhibitors (11 of 17). Several newer treatments were also described, including ustekinumab and JAK inhibitors.

CONCLUSIONS

This systematic review provides a comprehensive summary of recently published treatments for NL. As the existing data comes predominantly from case reports and series, statistical conclusions are not assessed. A greater number of randomized controlled trials with standardized endpoints are necessary to compare treatment efficacy.

Photodynamic therapy in pediatric age: Current applications and future trends

Photodynamic therapy (PDT) is a photochemotherapy based on local application of a photosensitive compound and subsequent exposure to a light source of adequate wavelength. It is a non-invasive therapeutic procedure widely used in oncodermatology for treatment of numerous skin cancers, but in the last years its use has been gradually extended to an increasing list of skin diseases of both infectious and inflammatory nature. Although PDT is proven as a safe and effective therapeutic option in adults, its use is not well standardized in the pediatric population. In this review, we will focus on clinical applications, mechanisms of action, protocols, and adverse events in children and adolescents. Most of pediatric experiences concerned treatment of skin cancers in Gorlin syndrome and xeroderma pigmentosum, acne vulgaris, and viral warts, but other applications emerged, such as cutaneous lymphoma and pseudo-lymphomas, necrobiosis lipoidica, hidradenitis suppurativa, dissecting cellulitis, leishmaniasis, angiofibromas, verrucous epidermal nevus, and linear porokeratosis. In these pediatric diseases, PDT appeared as an effective therapeutic alternative. The results on vitiligo were limited and not fully encouraging. Although highly versatile, PDT is not a therapy for all skin diseases, and a deeper knowledge of its mechanisms of action is required to better define its spectrum of action and safety in pediatric patients.

Comorbidity and Therapeutic Approaches in Patients with Necrobiosis Lipoidica

BACKGROUND

Necrobiosis lipoidica (NL) is a rare granulomatous disorder of unknown aetiology. Randomized controlled studies are not available due to it being an orphan disease.

OBJECTIVES

We evaluated patients in 2 dermatological centres to cluster data about epidemiology, the therapeutic approaches for NL, and their efficacy.

MATERIALS AND METHODS

Comorbidity and the efficacy of the applied treatment was assessed for 98 patients.

RESULTS

We identified 54% of patients with concomitant diabetes and 19% with thyroidal disorders. Topical steroids (85.7%) were predominantly used followed by calcineurin inhibitors (31%) and phototherapy (41.8%). Systemically, fumaric acid esters were more frequently applied (26.8%) than steroids (24.4%) and dapsone (24.4%). Steroids, compression therapy, calcineurin inhibitors, phototherapy, fumaric acid esters, and dapsone showed remarkable efficacy.

CONCLUSION

Therapeutic options were chosen individually in accordance with the severity of NL and presence of ulceration. Topical calcineurin inhibitors, systemic application of fumaric acid esters, and dapsone represent effective alternatives to the use of steroids.

Laser and light therapies for the treatment of necrobiosis lipoidica

Necrobiosis lipoidica (NL) is a rare, inflammatory granulomatous skin disorder involving collagen degeneration. In recent years, several light and laser therapies have been proposed and used in the treatment of NL with variable outcomes. The aim of the study was to investigate the efficacy and safety of lasers and light therapies for the treatment of NL. A review of PubMed was conducted to search for studies using laser and light therapies for the treatment of NL. Articles that employed a combination of treatment modalities were excluded. Twenty-four studies were reviewed. Light and laser therapies used in these studies included CO₂ laser, pulsed dye laser, methyl aminolevulinate (MAL)-photodynamic therapy (PDT), aminolevulinic acid (ALA)-PDT, ultraviolet A1 (UVA1) phototherapy, and psoralen plus ultraviolet-A (PUVA). PUVA was identified as the modality with the most available evidence (7 studies), followed by MAL-PDT and ALA-PDT (5 studies each), pulsed dye laser and UVA1 (3 studies each), and lastly CO₂ laser (2 studies). Most modalities demonstrated variable efficacies and side effects with the exception of PDL, which consistently showed successful outcomes. Multiple dermatologic light and laser therapies have been investigated for the treatment of NL, including PUVA, ALA-PDT, MAL-PDT, pulsed dye laser, UVA1, and CO₂ laser. However, a clear consensus on the preferred treatment is yet to be addressed. Each treatment option demonstrates both advantages and disadvantages that should be discussed with patients when selecting the treatment modality.

A Critical Reappraisal of Off-Label Use of Photodynamic Therapy for the Treatment of Non-Neoplastic Skin Conditions

BACKGROUND

In the past 30 years, topical photodynamic therapy (PDT) has been investigated for the treatment of a broad spectrum of cosmetic, inflammatory, and infectious skin conditions with variable, and often contrasting, results. However, the non-expert clinician may be in difficulty evaluating these results because different sensitizers, concentrations, formulations, light sources, and irradiation protocols have been used. In addition, many of these studies have poor quality design being case reports and uncontrolled studies of few cases.

SUMMARY

With the aim to clarify the potential usefulness of PDT for the treatment of infectious and inflammatory skin diseases as well as selected cosmetic indications, we searched for randomized controlled clinical trials, non-randomized comparative studies, retrospective studies, and case series studies with a number of at least 10 patients, published since 1990. Later, we reappraised the results in order to give a simple critical overview. Key Messages: Evidence from the literature seems to strongly support the use of ALA- and MAL-PDT for the treatment of common skin diseases such as acne, warts, condylomata, and Leishmania skin infection and for photorejuvenation, i.e., the correction of selected cosmetic changes of aging and photoaging. For other disorders, the level of evidence and strength of recommendation are lower, and controlled randomized studies with prolonged follow-ups are necessary in order to assess the clinical usefulness and other potential advantages over current treatment options.

European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 2: emerging indications - field cancerization, photorejuvenation and inflammatory/infective dermatoses

In addition to approved indications in non-melanoma skin cancer in immunocompetent patients, topical photodynamic therapy (PDT) has also been studied for its place in the treatment of, as well as its potential to prevent, superficial skin cancers in immune-suppressed patients, although sustained clearance rates are lower than for immune-competent individuals. PDT using a nanoemulsion of ALA in a daylight or conventional PDT protocol has been approved for use in field cancerization, although evidence of the potential of the treatment to prevent new SCC remained limited. High-quality evidence supports a strong recommendation for the use of topical PDT in photorejuvenation as well as for acne, refractory warts, cutaneous leishmaniasis and in onychomycosis, although these indications currently lack approvals for use and protocols remain to be optimized, with more comparative evidence with established therapies required to establish its place in practice. Adverse events across all indications for PDT can be minimized through the use of modified and low-irradiance regimens, with a low risk of contact allergy to photosensitizer prodrugs, and no other significant documented longer-term risks with no current evidence of cumulative toxicity or photocarcinogenic risk. The literature on the pharmacoeconomics for using PDT is also reviewed, although accurate comparisons are difficult to establish in different healthcare settings, comparing hospital/office-based therapies of PDT and surgery with topical ointments, requiring inclusion of number of visits, real-world efficacy as well as considering the value to be placed on cosmetic outcome and patient preference. This guideline, published over two parts, considers all current approved and emerging indications for the use of topical photodynamic therapy in Dermatology prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence.