Photodynamic photorejuvenation

Interaction of Cyanine-D112 with Binary Lipid Mixtures: Molecular Dynamics Simulation and Differential Scanning Calorimetry Study

This comprehensive molecular dynamics (MD) simulation and experimental study investigates the lipid bilayer interactions of dye D112 for potential photodynamic therapy (PDT) applications. PDT involves formation of a reactive oxidant species in the presence of a light sensitive molecule and light, interrupting cellular functions. D112 was developed as a photographic emulsifier, and we hypothesized that its combined cationic and lipophilic nature can render a superior photosensitizing property-crucial in various light therapies. The focus of this study is to elucidate the binding and insertion mechanisms of D112 with mixed lipid bilayers of anionic dipalmitoyl-phosphatidylserine (DPPS) and zwitterionic dipalmitoyl-phosphatidylcholine (DPPC) lipids to resemble cancer cell membranes. Our studies confirm initial electrostatic binding between the positively charged moieties of D112 and negatively charged lipid headgroups. Additionally, MD simulations combined with differential scanning calorimetry (DSC) studies confirm that D112-lipid interactions are governed by enthalpy-driven nonclassical hydrophobic effects in the membrane interior. It was further noted that despite the electrostatic preference of D112 toward the anionic lipids, D112 molecules colocalized on DPPC-rich domains after insertion. Atomistic level MD studies point toward two possible insertion mechanisms for D112: harpoon and flip. Further insights from the simulation showcase the interactions of low and high aggregates of D112 with the bilayer as the concentration of D112 increases in solution. The size of aggregates modulates the orientation and degree of insertion, providing important information for future studies on membrane permeation mechanisms.

Prospective study of intense pulsed light versus pulsed dye laser with or without blue light in the activation of PDT for the treatment of actinic keratosis and photodamage

BACKGROUND

Exposure to ultraviolet (UV) light from the sun is known to have a deleterious effect on the skin. Repeated insults to the dermal matrix from UV radiation result in the clinical signs of photodamage, including changes in skin elasticity, color, and texture. UV radiation also leads to the accumulation of DNA mutations and promotes tumor development, resulting in the formation of cutaneous precancerous and cancerous lesions. Continuous-wave incoherent blue light, intense pulsed light (IPL), and pulsed dye laser (PDL) are safe and efficacious light sources commonly used for aminolevulinic acid photodynamic therapy (PDT). The aim of this study was to prospectively evaluate the efficacy of PDT for the treatment of photodamage and actinic keratoses using four different combinations of light sources: PDL, PDL + blue light, IPL, and IPL + blue light.

STUDY

A total of 220 patients with either photodamage or actinic keratosis (AK) were recruited from the Miami Dermatology Laser Institute (Miami, FL) and were assigned prospectively to undergo one PDT treatment with one of the four light options: PDL, PDL + blue light, IPL or IPL + blue light. Of the 220 patients enrolled in treatment groups, 214 patients completed the study. Of the 214 patients, 88 received treatment for AK, and 126 received treatment for photodamage. All patients gave their consent to participate in the study and to allow their photographs to be utilized for the purpose of scientific presentations.

RESULTS

Treatment with IPL resulted in a 70.8% reduction of actinic keratoses at a 1-month follow-up. Treatment with IPL and blue light 84.4% reduction of actinic keratoses at 1 month follow up. Treatment with PDL 70.5% reduction of actinic keratoses at 1 month follow up. Treatment with PDL and blue light 69.3% reduction of actinic keratoses at 1 month follow up. Treatment with IPL resulted in an improvement score of 2.9. Treatment with IPL and blue light resulted in an improvement score of 3.0. Treatment PDL resulted in an improvement score of 1.5. Treatment with PDL and blue light resulted in an improvement score of 1.8.

CONCLUSION

Although all four treatment groups led to some improvement in signs of photoaging, IPL + blue light again demonstrated increased efficacy when compared to IPL, PDL, and PDL + blue light treatment groups. Results from our study were limited by an unequal distribution between treatment groups and a lack of follow-up beyond a 1-month period and warrant further research.

[Photodynamic therapy-trends and new developments]

Photodynamic therapy (PDT) is a licensed and established procedure for the treatment of actinic keratosis, basal cell carcinoma, and Bowen's disease, but there are several new and clinically relevant developments and trends. These concern on the one hand the main components of PDT, which are the photosensitizer and the light source. Furthermore, modifications and therapy combinations have been developed that lead to an improved therapeutic efficacy. An important aspect of field-directed PDT is also skin cancer prevention. Finally, PDT has been used successfully for nonlicensed indications including inflammatory diseases and skin rejuvenation. This article focuses on these new developments and on recent guideline recommendations.

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.

Photodynamic Therapy Activated by Intense Pulsed Light in the Treatment of Nonmelanoma Skin Cancer

Photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) or methyl aminolevulinate (MAL) has proven to be a highly effective conservative method for the treatment of actinic keratosis (AK), Bowen’s disease (BD), and superficial basal cell carcinoma (sBCC). PDT is traditionally performed in association with broad-spectrum continuous-wave light sources, such as red or blue light. Recently, intense pulsed light (IPL) devices have been investigated as an alternative light source for PDT in the treatment of nonmelanoma skin cancers (NMSC). We herein report our observational findings in a cohort of patients with a diagnosis of AK, sBCC, and BD that is treated with MAL-PDT using IPL, as well as we review published data on the use of IPL-PDT in NMSC.

Daylight photodynamic therapy versus cryosurgery for the treatment and prophylaxis of actinic keratoses of the face - protocol of a multicenter, prospective, randomized, controlled, two-armed study

BACKGROUND

Photodynamic therapy with daylight (DL-PDT) is efficacious in treating actinic keratosis (AK), but the efficacy of field-directed, repetitive DL-PDT for the treatment and prophylaxis of AK in photodamaged facial skin has not yet been investigated.

METHODS/DESIGN

In this multicenter, prospective, randomized, controlled, two-armed, observer-blinded trial, patients with a minimum of 5 mild-to-moderate AK lesions on photodamaged facial skin are randomly allocated to two treatment groups: DL-PDT with methyl aminolevulinate (MAL) and cryosurgery. In the DL-PDT group (experimental group), 5 treatments of the entire face are conducted over the course of 18 months. After preparation of the lesion and within 30 min after MAL application, patients expose themselves to daylight for 2 h. In the control group, lesion-directed cryosurgery is conducted at the first visit and, in the case of uncleared or new AK lesions, also at visits 2 to 5. The efficacy of the treatment is evaluated at visits 2 to 6 by documenting all existing and new AK lesions in the face. Cosmetic results and improvement of photoaging parameters are evaluated by means of a modified Dover scale. Primary outcome parameter is the cumulative number of AK lesions observed between visits 2 and 6. Secondary outcome parameters are complete clearance of AK, new AK lesions since the previous visit, cosmetic results independently evaluated by both patient and physician, patient-reported pain (visual analogue scale), patient and physician satisfaction scores with cosmetic results, and patient-reported quality of life (Dermatology Life Quality Index). Safety parameters are also documented (adverse events and serious adverse events).

DISCUSSION

This clinical trial will assess the efficacy of repetitive DL-PDT in preventing AK and investigate possible rejuvenating effects of this treatment. (Trial registration: ClinicalTrials.gov Identifier: NCT02736760).

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02736760 . Study Code Daylight_01. EudraCT 2014-005121-13.

Topical 5-aminolevulinic photodynamic therapy with red light vs intense pulsed light for the treatment of acne vulgaris: A spilit face, randomized, prospective study

5-Aminolevulinic acid photodynamic therapy (ALA-PDT) has been an effective method for treating acne vulgaris. Red light is the most widely used light source while Intense pulsed lights (IPL) is reported effective and well-tolerated. The purpose of this study was to evaluate the efficacy and adverse reactions of ALA-PDT with red light on acne compared with ALA-PDT with IPL.12 patients were recruited in the randomized, prospective and split-face study. 5% ALA cream were applied on the whole face with 2 hours' incubation before narrow band LED(633 ± 10 nm, 36 ∼ 108J/cm²) on one side of face and IPL(590∼1200 nm, 15∼17J/cm²) on the other side. Three treatment sessions were administered with 2-week interval each time and 8 weeks' follow up. The number of the total acne lesions and inflammatory lesions of the side treated by red light-PDT showed a relatively higher reduction rate that that by IPL-PDT (P < 0.05). Significant PpIX fluorescence decrease was observed only for the group of red light (P < 0.05). Lower pain intensity numeric rating scale values and Investigator's Global Severity Assessment (IGA) grading for erythema of the IPL side were observed (P<0.05).The results suggested that both red light and IPL are effective for ALA-PDT on acne vulgaris. ALA-PDT with red light may achieve better efficacy by more effective photobleaching of protoporphyrin IX (PpIX), whereas IPL may accomplish less adverse reactions and better tolerance.

[Photodynamic therapy in dermatology, other indications and perspectives]

PDT licensed indications in dermatology are actinic keratosis, Bowen's disease and superficial basal cell carcinomas. Skin tumors are sensitized by methyl aminomevulinate then illuminated with red light. Beyond these indication PDT is now widely used for the treatment of various others skin tumors and infectious or inflammatory skin disorders. PDT treatment of large areas can induce intense pain. Optimising PDT treatment needs to optimize pain control. Freezing or cooling procedure is the best way to decrease pain. The most interesting aspects of PDT is the absence of severe delayed adverse events and an optimal healing.

Photodynamic therapy for skin rejuvenation: review and summary of the literature--results of a consensus conference of an expert group for aesthetic photodynamic therapy

Skin rejuvenating effects of photodynamic therapy (PDT) for photoaged skin has been well-documented in several clinical trials. Different photosensitizers (5-aminolevulinic acid, methyl aminolevulinate) and diverse light sources (light-emitting diodes, lasers, intense pulsed light) have been used with promising results. An improvement of lentigines, skin roughness, fine lines and sallow complexion has been achieved with PDT. These clinically evident effects are at least in part due to histologically proven increase of collagen and decrease of elastotic material in the dermis. Effective improvement of photoaged skin, simultaneous treatment and possibly also prevention of actinic keratoses, the possibility of repeated treatments and, in contrast to other procedures, limited and calculable side effects make PDT a promising procedure for skin rejuvenation.

Photodynamic therapy for acne vulgaris: a critical review from basics to clinical practice: part II. Understanding parameters for acne treatment with photodynamic therapy

Photodynamic therapy requires a photosensitizer, oxygen, and activating light. For acne, pilosebaceous units are "target" structures. Porphyrins are synthesized in vivo from 5-aminolevulinic acid (ALA), particularly in pilosebaceous units. Different photosensitizers and drug delivery methods have been reported for acne treatment. There are a variety of porphyrin precursors with different pharmacokinetic properties. Among them, ALA and methyl-ester of ALA (MAL) are available for possible off-label treatment of acne vulgaris. In addition, various light sources, light dosimetry, drug incubation time, and pre- and posttreatment care also change efficacy and side effects. None of these variables has been optimized for acne treatment, but a number of clinical trials provide helpful guidance. In this paper, we critically analyze clinical trials, case reports, and series of cases published through 2009.

LEARNING OBJECTIVES

After completing this learning activity, participants should be able to analyze photodynamic therapy using 5-aminolevulinic acid and its derivates for acne treatment, predict the effectiveness and outcomes of photodynamic therapy using different parameters and/or different porphyrin-related photosensitizers, and assess and manage the side effects of porphyrin-based photodynamic therapy for acne.

Photodynamic therapy in dermatology: a review

Photodynamic therapy (PDT) is used for the prevention and treatment of non-melanoma skin cancer. Until recently, clinically approved indications have been restricted to actinic keratoses, nodular and superficial basal cell carcinoma, and, since 2006, Bowen disease. However, the range of indications has been expanding continuously. PDT is also used for the treatment of non-malignant conditions such as acne vulgaris and leishmaniasis, as well as for treating premature skin aging due to sun exposure. The production of reactive oxygen intermediates like singlet oxygen depends on the light dose applied as well as the concentration and localization of the photosensitizer in the diseased tissue. Either cytotoxic effects resulting in tumor destruction or immunomodulatory effects improving inflammatory skin conditions are induced. Treating superficial non-melanoma skin cancer, PDT has been shown to be highly efficient, despite the low level of invasiveness. The excellent cosmetic results after treatment are beneficial, too.

Technology approaches to the medical spa: art plus science equal rejuvenation

Medical spas are the fasting growing segment of the 15-billion dollar spa industry. Although medical spas have been in existence since ancient times to treat a wide variety of ailments such as gout, arthritis, and diabetes, our modern concept of the medical spa combines relaxation with medical rejuvenative procedures. This article focuses on the more recent technologic advancements in rejuvenation.

The spectrum of laser skin resurfacing: nonablative, fractional, and ablative laser resurfacing

The drive to attain cosmetic facial enhancement with minimal risk and rapid recovery has inspired the field of nonsurgical skin rejuvenation. Laser resurfacing was introduced in the 1980s with continuous wave carbon dioxide (CO(2)) lasers; however, because of a high rate of side effects, including scarring, short-pulse, high-peak power, and rapidly scanned, focused-beam CO(2) lasers and normal-mode erbium-doped yttrium aluminium garnet lasers were developed, which remove skin in a precisely controlled manner. The prolonged 2-week recovery time and small but significant complication risk prompted the development of non-ablative and, more recently, fractional resurfacing in order to minimize risk and shorten recovery times. Nonablative resurfacing produces dermal thermal injury to improve rhytides and photodamage while preserving the epidermis. Fractional resurfacing thermally ablates microscopic columns of epidermal and dermal tissue in regularly spaced arrays over a fraction of the skin surface. This intermediate approach increases efficacy as compared to nonablative resurfacing, but with faster recovery as compared to ablative resurfacing. Neither nonablative nor fractional resurfacing produces results comparable to ablative laser skin resurfacing, but both have become much more popular than the latter because the risks of treatment are limited in the face of acceptable improvement.

LEARNING OBJECTIVES

At the completion of this learning activity, participants should be familiar with the spectrum of lasers and light technologies available for skin resurfacing, published studies of safety and efficacy, indications, methodologies, side effects, complications, and management.

[Photodynamic therapy: non-oncologic indications]

While efficacy of topical photodynamic therapy (PDT) for the treatment of superficial non-melanoma skin cancer is already well-proven by several controlled clinical trials, there are only a few controlled studies showing efficacy of PDT for non-oncologic skin disorders. This report provides information on the use of PDT for inflammatory skin disorders, disorders of the pilosebaceous unit, infections of the skin, sclerotic skin diseases and cosmetic indications.

Split-face-study using two different light sources for topical PDT of actinic keratoses:non-inferiority of the LED system

BACKGROUND

Photodynamic therapy (PDT) with 5-amino-4-oxo-pentanoate (methylaminolevulinate, MAL) is an effective and safe treatment option for actinic keratoses. Light-emitting diodes (LED) are suitable light sources for topical PDT. To evaluate the efficacy, painfulness, patient satisfaction and cosmesis of LED-based PDT a prospective, randomized and controlled split-face study was performed.

METHODS

Topical ALA-PDT was administered to 17 patients whose actinic ker-atoses (n = 131) were symmetrically distributed and suitable for a two-side comparison. After incubation with MAL (16%), irradiation was performed with the incoherent lamp (160 mW cm(-2); 100 J cm(-2), PDT 1200L, Waldmann Medizintechnik, Villingen-Schwenningen, Germany) on one side and the LED system (120 mW cm(-2); 40 J cm(-2), LEDA, WaveLight AG, Erlangen, Germany) on the other side. The patients were followed by re-evaluation up to 6 months.

RESULTS

Six months following treatment there was no significant difference between the infiltration and keratosis scores in both treatment regimes (p = 0.812). The remission rate was 78.5% (LED system) vs.80.3% (incoherent lamp). There was no significant difference between both light sources regarding the pain during therapy (p = 0.988). There was no significant difference between both treatment regimes regarding patient satisfaction (p = 1).

CONCLUSIONS

LEDA-based MAL-PDT is an effective alternative for the treatment of atinic keratoses. The remission rates and cosmetic results are not inferior to PDT using incoherent light systems. Both treatment regimes are similarly painful.

Photodynamic therapy: update 2006. Part 2: Clinical results

In several randomized, controlled studies, the application of a standard preparation containing methyl-aminolevulinate (MAL; Metvix, Galderma, F), followed by red light irradiation proved effective and well tolerated in the treatment of actinic keratosis and basal cell carcinoma, and has now been approved for clinical use in European countries. A brand name aminolevulinic acid (ALA) solution (Levulan Kerastick, Dusa Pharmaceuticals Inc., Wilmington, MA) plus blue light exposure has been approved for the treatment of actinic keratosis in the USA. Randomized and controlled studies have shown that MAL as well as ALA are also effective in the treatment of Bowen's disease. In addition, a large and growing number of open studies or case reports have evaluated its use in the treatment of a broad range of other neoplastic, inflammatory and infectious skin diseases. However, efficacy and definite advantages over standard therapies remain to be clarified because the experimental design of these studies was often poor, the number of enrolled patients was generally low, and the follow-up was shorter than 12 months. However, these studies have suggested a few possible clinical applications worthy of further investigation. A growing number of laboratory and clinical findings suggest that several new synthetic sensitizers, besides ALA and MAL, may be helpful in the treatment of non-melanoma skin cancers, melanoma metastasis, and selected inflammatory and infective skin diseases. These compounds are deliverable intravenously, have short half-lives both in the blood and skin, and are highly efficient. However, they are as of yet not approved for clinical use.

Variable pulsed light is less painful than light-emitting diodes for topical photodynamic therapy of actinic keratosis: a prospective randomized controlled trial

BACKGROUND

Photodynamic therapy (PDT) of actinic keratosis (AK) using methylaminolaevulinate (MAL) is an effective and safe treatment option, but the procedure is painful.

OBJECTIVES

To evaluate the efficacy and pain associated with variable pulsed light (VPL), a prospective, randomized, controlled split-face study was performed.

METHODS

Topical MAL-PDT was conducted in 25 patients with AK (n = 238) who were suitable for two-sided comparison. After incubation with MAL, irradiation was performed with a light-emitting diode (LED) (50 mW cm(-2); 37 J cm(-2)) vs. VPL (80 J cm(-2), double pulsed at 40 J cm(-2), pulse train of 15 impulses each with a duration of 5 ms, 610-950 nm filtered hand piece) followed by re-evaluation up to 3 months.

RESULTS

The pain during and after therapy was significantly lower with VPL irradiation [t (d.f. = 24) = 4.42, P < 0.001]. The overall mean +/- SD infiltration and keratosis score at 3 months after treatment was 0.86 +/- 0.71 (LED system) vs. 1.05 +/- 0.74 (VPL device) (no statistically significant difference; P = 0.292). Patient satisfaction following both treatment modalities did not significantly differ at the 3-month follow up (P = 0.425).

CONCLUSIONS

VPL used for MAL-PDT is an efficient alternative for the treatment of AK that results in complete remission and cosmesis equivalent to LED irradiation but causes significantly less pain.

Aminolevulinic Acid Photodynamic Therapy for Actinic Keratoses/Actinic Cheilitis/Acne: Vascular Lasers

The combination of newer laser and light sources, the long-pulsed pulsed dye laser (LP PDL) and intense pulsed light, with topical aminolevulinic acid photodynamic therapy (PDT) has achieved enhanced efficacy and rapid treatment and recovery, while diminishing unwanted side effects. In particular, LP PDL PDT has been shown to be safe and effective in the treatment of actinic keratoses, actinic cheilitis, photodamage, and acne vulgaris with minimal discomfort, rapid treatment and recovery, and excellent posttreatment cosmesis.

Aminolevulinic Acid-Photodynamic Therapy for Photorejuvenation

Light therapy is widely used in dermatology. An enhancement to his therapy is the use of a photosensitizing medication along with light therapy, known as photodynamic therapy (PDT). PDT is primarily used for the treatment of precancerous lesions, acne vulgaris, and nonmelonoma skin cancer, and has also been shown to improve the appearance of photodamaged skin. This article reviews the available literature for the treatment of photodamaged skin using PDT along with recent advancements in PDT for various dermatologic indications.

Photodynamic Therapy

ALA-PDT is a safe, well-tolerated, and effective treatment for many dermatologic conditions. Current data most strongly support its use in the treatment of actinic damage, but further investigation into alternative uses continues. Current efficacy is limited primarily by the depth of penetration of the photosensitizing agent and the activating light source. Even with this limitation, the potential applications of PDT are numerous. As new technology is developed to overcome current restraints, the future of PDT is wide open.

Laser-mediated photodynamic therapy

Photodynamic therapy (PDT) has evolved since its inception at the beginning of the 20th century, when it was defined as an oxygen-dependent reaction between a photosensitizing dye and light. Photosensitizers and light sources have since been continually optimized for distinct applications and tissues. Systemic porphyrins, such as hematoporphyrin, were the first photosensitizers to be used, mostly to treat tumors. The first light sources used were broad-band, noncoherent lights, such as quartz, xenon, tungsten, or halogen lamps. The wavelengths of light chosen were based upon the absorption spectrum of porphyrins: blue because the largest peak is at 400 nm (the Soret band) and red because of its greater penetration depth but lesser absorption at 650 nm (a Q band). Systemic photosensitizers caused prolonged photosensitivity, and broad-band light sources had limitations and side effects. The development of topical photosensitizers, such as 5-aminolevulinic acid, and the advent of lasers in recent years have advanced PDT for cutaneous use. In the 1990s, red lasers were applied to PDT because of their increased skin penetration despite lesser absorption by porphyrins. Broad-band blue light and red light have been studied extensively, the former achieving Food and Drug Administration approval in combination with topical aminolevulinic acid for the treatment of actinic keratosis in 1997. These lasers and light sources caused significant side effects, such as discomfort, erythema, crusting, blistering, and dyspigmentation. The recent application of the long-pulsed pulsed dye laser (595 nm) after topical aminolevulinic acid greatly minimized side effects without compromising efficacy. Long-pulsed pulsed dye laser-mediated PDT has since been shown to be effective in treatment of actinic keratosis, actinic cheilitis, sebaceous hyperplasia, lichen sclerosus, and, most recently, acne vulgaris. Finally, intense pulsed light sources have been introduced to PDT for the treatment of photodamage and acne, offering advantages of versatility in wavelengths and applications.

Photodynamic therapy for cosmetic applications

With the advent of short contact and pulsed light techniques, topical 5-aminolevulinic acid photodynamic therapy (5-ALA PDT) has become a viable clinical modality. Intense pulsed light, the pulsed dye laser, and blue light-emitting lamps have become the most commonly used devices in inducing a cosmetic PDT effect. More recently, by combining the photothermal effects of pulsed light with the photochemical effects of PDT, an enhanced cosmetic effect has been demonstrated in a variety of dermatologic conditions. In addition, the use of shorter 5-ALA incubation times allows for improved patient tolerance during treatment and subsequently fewer adverse effects in the postoperative period. A review of the current literature on cosmetic uses of PDT as well as our personal techniques are discussed in detail.

5-aminolevulinic acid photodynamic therapy: where we have been and where we are going

BACKGROUND

Photodynamic therapy, utilizing the topical administration of 20% 5-aminolevulinic acid, has generated a great deal of interest in the dermatology community over the past several years.

OBJECTIVE

The purpose of this article is to review the history of photodynamic therapy in dermatology and to review recent new advances with this technology that will increase its appeal to all dermatologists.

METHODS

A literature review and results of new clinical trials with regards to photorejuvenation and acne vulgaris treatments with 5-aminolevulinic acid photodynamic therapy are presented.

RESULTS

Short-contact, full-face 5-aminolevulinic acid photodynamic therapy treatments with a variety of lasers and light sources have shown to be successful in treating all facets of photorejuvenation and the associated actinic keratoses as well as disorders of sebaceous glands, including acne vulgaris. The treatments are relatively pain-free, efficacious, and safe. They are also making already available laser/light source therapies work better for acne vulgaris and photorejuvenation.

CONCLUSIONS

The use of 5-aminolevulinic acid photodynamic therapy with short-contact, full-face broad-application therapy is now able to bridge the world of medical and cosmetic dermatologic surgery. This therapy is available for all dermatologists to utilize in the care of their patients.

Topical treatment strategies for non-melanoma skin cancer and precursor lesions

The ability to manage non-melanoma skin cancers and pre-malignant lesions with topical pharmacologic agents is highly compelling. This article examines currently available products and discusses their emerging roles and limitations. These include fluorouracil, diclofenac sodium, imiquimod, and photodynamic therapy.

Topical photodynamic therapy in clinical dermatology

The growing incidence of cutaneous malignancies each year necessitates the development of new and more effective methods for both the diagnosis and the treatment of cancerous lesions, while assuring better cosmetic results and improving patient satisfaction. With that in mind, the use of topical photodynamic therapy (PDT) has been explored in the treatment as well as the diagnosis of various cutaneous malignancies. Using the intrinsic cellular haem biosynthetic pathway and principles of photoillumination, topical PDT carries the goal of selectively targeting abnormal cells, while preserving the normal surrounding structures. This paper will discuss the various applications and data on the use of topical PDT in dermatology.

Actinic Keratosis: The Key Event in the Evolution from Photoaged Skin to Squamous Cell Carcinoma

Skin aging is the result of intrinsic and extrinsic factors. Extrinsic aging, also called photoaging, is mainly caused by ultraviolet radiation from the sun and leads to a state which has been termed dermatoheliosis. The aim of this article is to provide an overview of photoaged skin addressing actinic keratoses (AKs) in particular. This review will describe the clinical features of photoaged skin and briefly summarize the underlying histological, photobiochemical and molecular mechanisms responsible for photoaging. The concept of the disease continuum from AK to squamous cell carcinoma will also be presented. A special focus will be on established and new therapeutic approaches to undo photoinduced skin damage.

Topical photodynamic therapy: a new tool in cosmetic dermatology

Topical photodynamic therapy is an evolving relatively new modality in dermatology. While widely used in Europe for treatment of actinic keratoses and skin cancer, topical photodynamic therapy is still relatively unfamiliar in the United States. Approved by the US Food and Drug Administration in 1999, photodynamic therapy is now being evaluated for superficial epidermal tumors, acne, and cosmetic applications. This article reviews recent advances in this field, with emphasis on skin rejuvenation, acne, and hair removal.