Photodynamic therapy for actinic keratosis in organ transplant patients

The "Personalising Actinic Keratosis Treatment for Immunocompromised Patients" (IM-PAKT) Project: An Expert Panel Opinion

Actinic keratosis (AK) is an intraepithelial condition characterized by the development of scaly, erythematous lesions after repeated exposure to ultraviolet radiation. Significant immunosuppression is a risk factor for the development of AK and subsequent lesion progression to squamous cell carcinoma. Immunocompromised patients (ICPs), particularly organ transplant recipients, often have more advanced or complex AK presentations and an increased risk of skin carcinomas versus non-ICPs with AK, making lesions more difficult to treat and resulting in worse treatment outcomes. The recent "Personalising Actinic Keratosis Treatment" (PAKT) consensus reported that delivering patient-centric care may play a role in supporting better clinical outcomes and patient satisfaction with treatments for chronic dermatologic conditions such as AK, which require repeated cycles of treatment. Additionally, currently published guidance and recommendations were considered by the PAKT panel to be overly broad for managing ICPs with their unique and complex needs. Therefore, the "Personalising Actinic Keratosis Treatment for Immunocompromised Patients" (IM-PAKT) panel was established to build upon general recommendations from the PAKT consensus. The panel identified current gaps in guidance for AK care in ICPs, offered practical care approaches based on typical ICP scenarios, and highlighted the need to adapt AK management to optimize care and improve treatment outcomes in ICPs. In particular, dermatologists should establish collaborative and transparent relationships with patients' multidisciplinary teams to enhance overall care for patients' comorbidities: given their increased risk of progression to malignancy, earlier assessments/interventions and frequent follow-ups are vital.The panel also developed a novel "triage" tool outlining effective treatment follow-up and disease surveillance plans tailored to patients' risk profiles, guided by current clinical presentation and relevant medical history. Additionally, we present the panel's expert opinion on three fictional ICP scenarios to explain their decision-making process for assessing and managing typical ICPs that they may encounter in clinical practice.

Application of microneedling in photodynamic therapy: A systematic review

BACKGROUND

The application of photodynamic therapy (PDT) is pivotal in the management of diverse dermatologic conditions. Microneedling (MN) is a minimally invasive tool that is capable of inducing transient pores on the skin to facilitate transdermal drug delivery. Several studies have reported augmentation of PDT combined with MN. This systematic review analyzes the current studies on the efficacy and safety of MN-assisted PDT for skin diseases.

METHODS

The literature search using the PRISMA standard was completed through PubMed, Embase, Web of Science and CENTRAL from the establishment of the databases to November 2023. Two independent researchers finished the procedure.

RESULTS

A total of 12 articles and 413 subjects met our study criteria. This systematic review suggests that MN-assisted PDT can decrease the incubation time required for the photosensitizer and reduce skin lesions of actinic keratosis (AK) . The common side effect is pain and no serious adverse events were reported.

CONCLUSIONS

MN is an effective method to increase the transdermal delivery rate of photosensitizers. For different photosensitizers and disease, MN may show different clinical effects.

Actinic Keratosis in Solid Organ Transplant Recipients: A Medical Literature Review

Pharmacological immunosuppression in solid organ transplant recipients is a significant risk factor in the occurrence of actinic keratosis (AK) and later progression into squamous cell carcinomas (SCC). Treating clinical and preclinical lesions is mandatory in this group of patients due to the high changes of progression into SCC. On the other hand, prevention of AK should be considered because it plays a crucial role. Several studies have been published on immunocompetent patients, as well as on the management and prevention of AK, but not on immunosuppressed patients. This review aims to summarize the current knowledge on the management and prevention measures of AK in solid organ transplant recipients.

[Translated article] Actinic Keratosis in Solid Organ Transplant Recipients: A Medical Literature Review

Pharmacological immunosuppression in solid organ transplant recipients is a significant risk factor in the occurrence of actinic keratosis (AK) and later progression into squamous cell carcinomas (SCC). Treating clinical and preclinical lesions is mandatory in this group of patients due to the high changes of progression into SCC. On the other hand, prevention of AK should be considered because it plays a crucial role. Several studies have been published on immunocompetent patients, as well as on the management and prevention of AK, but not on immunosuppressed patients. This review aims to summarize the current knowledge on the management and prevention measures of AK in solid organ transplant recipients.

Secure transplantation by tissue purging using photodynamic therapy to eradicate malignant cells

The field of photodynamic therapy (PDT) for treating various malignant neoplasms has been given researchers' attention due to its ability to be a selective and minimally invasive cancer therapy strategy. The possibility of tumor cell infection and hence high recurrence rates in cancer patients tends to restrict autologous transplantation. So, the photodynamic tissue purging process, which consists of selective photoinactivation of the malignant cells in the graft, is defined as a compromising strategy to purify contaminated tissues before transplantation. In this strategy, the direct malignant cells' death results from the reactive oxygen species (ROS) generation through the activation of a photosensitizer (PS) by light exposure in the presence of oxygen. Since new PS generations can effectively penetrate the tissue, PDT could be an ideal ex vivo tissue purging protocol that eradicates cancer cells derived from various malignancies. The challenge is that the applied pharmacologic ex vivo tissue purging should efficiently induce tumor cells with minor influence on normal tissue cells. This review aims to provide an overview of the current status of the most effective PDT strategies and PS development concerning their potential application in ex vivo purging before hematopoietic stem cell or ovarian tissue transplantation.

Ablative Fractional Laser-assisted Low-irradiance Photodynamic Therapy for Treatment of Actinic Keratoses in Organ Transplant Recipients: A Prospective, Randomized, Intraindividual Controlled Trial

Pain and inferior efficacy are major limiting factors of conventional photodynamic therapy for the field treatment of actinic keratoses in immunosuppressed organ transplant recipients. This prospective randomized controlled study evaluates the efficacy and tolerability of ablative fractional laser system pretreatment combined with low-irradiance photodynamic therapy (18.5 mW/cm2) compared with conventional photodynamic therapy (61.67 mW/cm2) in the treatment of actinic keratoses on the face and scalp in organ transplant recipients, using a red light-emitting diode lamp at a total light dose of 37 J/cm2. Low-irradiance photodynamic therapy combined with Er:YAG pretreatment achieved a significantly superior lesion response rate (mean ± standard deviation 77.3 ± 23.6%) compared with conventional photodynamic therapy (61.8 ± 21.4%; p = 0.025) in intra-individual fields at 3 months without negatively impacting pain (p = 0.777) or cosmetic outcome (p = 0.157).

Skin Cancers and Lung Transplant

It is well known that solid-organ transplant recipients (SOTRs) have a 65- to 100-fold increase in the risk of developing skin cancer, namely, nonmelanoma skin cancers (NMSCs) such as cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC). In addition, these patients are also at increased risk for development of melanoma as well as other less common cutaneous malignancies (Merkel's cell carcinoma, Kaposi's sarcoma). SOTRs with NMSC (namely cSCC) are also at significantly increased risk of poor clinical outcomes including local recurrence, nodal and distant metastasis, and disease-specific death relative to patients who are not immunosuppressed. Increased surveillance and monitoring in patients at risk of aggressive disease and poor outcomes who are on immunosuppression is essential in patients with lung transplants given the high degree of immunosuppression. Increased awareness of risks, treatments, and management allows for improved outcomes in these patients. This article will provide an overview of the risk factors for the development of cutaneous malignancies in organ transplant recipients as well as a detailed discussion of various immunosuppressant and prophylactic medications used in this patient population that contribute to the risk of developing cutaneous malignancies, with an emphasis on NMSC (cSCC and BCC) in lung transplant recipients. Finally, this article includes a discussion on the clinical and dermatologic management of this high-risk immunosuppressed population including a review of topical and systemic agents for field therapy of actinic damage and chemoprevention of keratinocyte carcinomas. In addition, indications for additional treatment and preventive measures such as adjuvant radiation treatment after surgical management of cutaneous malignancies and potential modification of immunosuppressive medication regimens are discussed.

Update: Solar UV Radiation, Vitamin D, and Skin Cancer Surveillance in Organ Transplant Recipients (OTRs)

Although great progress has been achieved during the last decades, the clinical management of organ transplant recipients (OTRs) remains a challenge. OTRs need in general lifelong immunosuppressive therapy that is associated with an increased risk to develop skin cancer and with an unfavorable clinical outcome of these malignancies. Skin cancer prevention measures, including regular full-body examinations, are therefore necessary in OTRs to detect and treat suspicious lesions at an early stage. The frequency of aftercare depends on the individual risk factors of the patient. Patients should apply consistent sun protection with sunscreens and clothing, as well as a monthly self-examination. On the other hand, the need of UVR avoidance increases the risk of vitamin D deficiency, which itself is associated with an increased risk for many diseases, including malignancies. OTRs should therefore be monitored for 25(OH)D status and/or should take vitamin D supplements. It has to be emphasized that an interdisciplinary approach, coordinated by the transplant center, that includes regular skin examinations by a dermatologist, is needed to ensure the best care for the OTRs.

Daylight photodynamic therapy for prevention of new actinic keratosis and keratinocyte carcinomas in organ transplants. A cryotherapy-controlled randomized clinical trial

BACKGROUND

Organ transplant recipients (OTR) have a higher risk of actinic keratosis (AK) and keratinocyte carcinomas (KC). There are no clinical trials assessing the effectiveness of daylight photodynamic therapy (DPDT) to prevent new AK and KC in OTR.

OBJECTIVES

To determine whether repeated treatments of field cancerization with DPDT are effective in preventing new AK and KC in OTR.

METHODS

A randomized, intra-subject controlled, evaluator-blind, split-face and/or scalp trial, from April 2016 to October 2018. Participants were OTR older than 18 years, 1-year posttransplant, with at least 5 AK on each hemi-face/hemi-scalp. One side received six field treatments with DPDT: two sessions 15 days apart at baseline, two at 3 months and two at 9 months after baseline. Control side received lesion-directed treatment with cryotherapy (double freeze-thaw) at baseline, 3 and 9 months. Total number of lesions (AK and KC) at 21 months, number of new AK and KC at 3, 9, 15 and 21 months and treatment preferences were analysed.

RESULTS

Of 24 men included, 23 were analysed at 3 months; and 21, at 9, 15 and 21 months. Mean (SD) age was 69.8 years (9.2). The total number of lesions at 21 months was 4.7 (4.3) for DPDT and 5.8 (5.0) for control side; P = 0.09. DPDT showed significantly lower means [SD] of new lesions compared to control side at 3 months (4.2 [3.4] vs. 6.8 [4.8]; P < 0.001), 9 months (3.0 [3.3] vs. 4.3 [3.4]; P = 0.04) and 15 months (3.0 [4.6] vs. 4.8 [5.0]; P = 0.02), and non-significant at 21 months (3.7 [3.5] vs. 5.0 [4.5]; P = 0.06). Most participants preferred DPDT.

CONCLUSION

DPDT showed potential effectiveness in preventing new AK and KC in OTR by consecutive treatments of field cancerization. The preference for DPDT could facilitate adherence to the long-term treatment necessary in these patients.

Platelet-Activating Factor as an Effector for Environmental Stressors

Environmental stressors exert a profound effect on humans. Many environmental stressors have in common the ability to induce reactive oxygen species. The goal of this chapter is to present evidence that the potent lipid mediator platelet-activating factor (PAF) is involved in the effects of many stressors ranging from cigarette smoke to ultraviolet B radiation. These environmental stressors can generate PAF enzymatically as well as PAF-like lipids produced by free radical-mediated attack of glycerophosphocholines. Inasmuch as PAF exerts both acute inflammation and delayed immunosuppressive effects, involvement of the PAF system can provide an explanation for many consequences of environmental stressor exposures.

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: A targeted literature review focussing on outcomes and optimisation in solid organ transplant recipients

Squamous cell carcinoma incidence is 65- to 250-fold in solid organ transplant recipients, BCC is 10-fold and in Australia, rates of skin cancer in solid organ transplant recipients reach 70-82% prevalence within the first 20 years; hence, effective, evidence-based treatment of early and precancerous lesions is an essential tool in dermatological patient care. Photodynamic therapy is used to treat a range of conditions including actinic keratoses, squamous cell carcinoma in situ, superficial basal cell carcinoma and nodular basal cell carcinoma. A literature review was undertaken to examine the outcomes of photodynamic therapy in solid organ transplant recipients and methods of optimising outcomes in solid organ transplant recipients. Study sizes were small and protocols varied widely, so meta-analysis was not possible; however, photodynamic therapy appears to be an acceptable treatment for approved indications in solid organ transplant recipients in whom ongoing surveillance is maintained to ensure clearance and detect recurrence. Methods for improving efficacy were also reviewed for this population. Improved outcomes may be achieved by combining photodynamic therapy with other local methods such as 5-fluorouracil or ablative fractional laser.

Management of actinic keratosis at specific body sites in patients at high risk of carcinoma lesions: expert consensus from the AKTeam™ of expert clinicians

Actinic keratoses (AK) arise on sun-exposed regions of the skin. If left untreated, AK may progress to invasive squamous cell carcinoma (SCC), although the rate of progression is low. A practical treatment algorithm for the treatment of AK in standard situations has been published by the AKTeam^™ expert panel. However, management of particular situations of AK with increasing/higher carcinoma risk or AK progressing into carcinomas with increased aggressiveness due to their anatomical location (risky areas), or in patients with an increased risk of SCC requires further discussion. These include AK on the dorsal hands, forearms, legs, periorbital region, eyelids, ears, or lips, and organ transplant recipients, patients undergoing treatment with carcinogenic agents and patients with chronic lymphocytic leukaemia. The main objective was to propose therapeutic strategies for the treatment of AK located in risky areas and in patients with more invasive/aggressive lesions and a higher risk of progression to SCC. A systematic review of the literature was initially performed, and results were discussed by the experts to propose best management practices in specific situations. Finally, adapted management strategies for AK occurring in risky areas and in high-risk patients are presented, taking into account the experts' own clinical experience and current guidelines. In most of these 'at-risk' situations, patients can be treated according to the AKTeam^™ treatment algorithm. Difficult-to-treat lesions should be treated more aggressively due to their higher risk of transformation. For patients with skin that is highly susceptible to actinic damage, monitoring and sun protection strategies are mandatory, and patients should undergo more regular follow-up. Further assessment of newer therapies in clinical trials is necessary to determine optimal treatment conditions. This expert consensus provides guidance for the management of AK in risky body sites and in patients with an increasing/higher risk for SCCs.

Photodynamic therapy in dermatology beyond non-melanoma cancer: An update

Photodynamic therapy (PDT) employs a photosensitizer (PS) and visible light in the presence of oxygen, leading to production of cytotoxic reactive oxygen species, which can damage the cellular organelles and cause cell death. In dermatology, PDT has usually taken the form of topical application of a precursor in the heme biosynthesis pathway, called 5-aminolevulinic acid (or its methyl ester), so that an active PS, protoporphyrin IX accumulates in the skin. As PDT enhances dermal remodeling and resolves chronic inflamation, it has been used to treat cutaneous disorders include actinic keratoses, acne, viral warts, skin rejuvenation, psoriasis, localized scleroderma, some non-melanoma skin cancers and port-wine stains. Efforts are still needed to mitigate the side effects (principally pain) and improve the overall procedure.

Comparison of "Lesion-by-Lesion" and Field Photodynamic Therapy in the Prevention of Actinic Keratoses: A Randomized, Split-Face, Single-Blind Pilot Study

BACKGROUND

Actinic keratoses (AKs) are often treated separately, lesion by lesion. However, in the past years, AKs have been described as a field disease and not limited to single clinically apparent lesions. Treatment should therefore target an area of field change which may reduce the risk of development of further AKs, second tumours, and local recurrence.

OBJECTIVE

The primary objective was to determine the number of new lesions at 9 months after methyl aminolevulinate photodynamic therapy (MAL-PDT). Secondary objectives were to determine the number of new lesions at 3 and 6 months after treatment and the percentage reduction of AKs from baseline at 3, 6, and 9 months after MAL-PDT.

METHODS

This was a single-centre, prospective, randomized, split-face, investigator-blinded pilot study with a study duration of 1 year. The study population comprised patients with AKs on the face or scalp, with a maximum of 10 AKs on each side. One side was treated with 1 session of "lesion-by-lesion" MAL-PDT (LT side) and the other side with 1 session of field MAL-PDT (FT side).

RESULTS

At 9 months the FT demonstrated significantly fewer new lesions. At every time point during the follow-up, we found a significant reduction in the number of AKs in the LT as well as in the FT sides. After 3 and 6 months we did not observe significant differences between the sides. However, after 9 months, the LT area showed significantly fewer remaining AKs, whereas the FT area demonstrated significantly fewer new lesions.

CONCLUSIONS

Field treatment results in significantly fewer new AK lesions compared with lesion-by-lesion treatment.

Photodynamic Therapy and Non-Melanoma Skin Cancer

Non-melanoma skin cancer (NMSC) is the most common malignancy among the Caucasian population. Photodynamic therapy (PDT) is gaining popularity for the treatment of basal cell carcinoma (BCC), Bowen's disease (BD) and actinic keratosis (AK). A topical or systemic exogenous photosensitiser, results in selective uptake by malignant cells. Protoporphyrin IX (PpIX) is produced then activated by the introduction of a light source. Daylight-mediated MAL (methyl aminolaevulinate) PDT for AKs has the advantage of decreased pain and better patient tolerance. PDT is an effective treatment for superficial BCC, BD and both individual and field treatment of AKs. Excellent cosmesis can be achieved with high patient satisfaction. Variable results have been reported for nodular BCC, with improved outcomes following pretreatment and repeated PDT cycles. The more aggressive basisquamous, morphoeic infiltrating subtypes of BCC and invasive squamous cell carcinoma (SCC) are not suitable for PDT. Prevention of "field cancerization" in organ transplant recipients on long-term immunosuppression and patients with Gorlin syndrome (naevoid basal cell carcinoma syndrome) is a promising development. The optimisation of PDT techniques with improved photosensitiser delivery to target tissues, new generation photosensitisers and novel light sources may expand the future role of PDT in NMSC management.

Photodynamic Photorejuvenation: A Review

INTRODUCTION

Topical photodynamic therapy (PDT) is acknowledged to be a safe and efficient therapeutic option for the selective destruction of actinic keratosis and superficial carcinomas. Over the past 15 years, topical PDT has also been shown to be a possible method for "photorejuvenation."

MATERIALS AND METHODS

An extensive review was performed of in vitro and in vivo (animals, organ transplant recipients, or immunocompetent patients) studies.

RESULTS

The studies point to a high level of efficacy. Tone, lentigos, skin roughness, and moreover texture and fine wrinkles because of the effects of dermal remodeling are improved. Adverse effects are generally described as mild to moderate, without scarring, along with a fast recovery time. Patients with fair phototypes and a history of sun exposure and actinic damage of varying severity are the best candidates for this technique. Photodynamic photorejuvenation sessions can both rejuvenate their skins and also treat their visible or incipient UV-induced lesions. New protocols either with daylight use and/or previous intensification by laser or microneedling seem promising.

CONCLUSION

The photodynamic rejuvenation technique seems to show excellent short-term efficacy and tolerability.

Primary prevention of skin dysplasia in renal transplant recipients with photodynamic therapy: a randomized controlled trial

Organ transplant recipients (OTRs) are at high risk of developing cutaneous squamous cell carcinoma (SCC); prevention includes early treatment of premalignant actinic keratosis (AK). Photodynamic therapy (PDT) is a noninvasive field therapy that reduces new AKs in patients with existing AK and delays SCC development in mice. We investigated the effect of repeated PDT over 5 years for primary prophylaxis of skin dysplasia. These data represent an interim analysis of an on-going randomized controlled trial. During 2008-2011, 25 renal transplant recipients with clinically normal skin were randomized to split-side PDT of the face, forearm and hand, the contralateral side serving as untreated control. Patients received PDT on inclusion and at 6-monthly intervals for 5 years. Blinded evaluation was performed at each visit. We found that prophylactic PDT significantly delayed onset of AK compared with untreated skin, p = 0.020. At 3-year follow-up, we observed AK in 63% of patients in untreated skin areas compared with 28% of patients in PDT-treated skin, with a total number of cumulated AKs in untreated skin (n = 43) compared with PDT-treated skin (n = 8), p = 0.005. These preliminary data indicate a novel approach to early prevention of skin dysplasia that may reduce morbidity from multiple AKs and SCCs in OTR.

Update on topical photodynamic therapy for skin cancer

Topical photodynamic therapy has become an established therapy option for superficial non-melanoma skin cancers with a substantial evidence base. In this update the increased choice in photosensitizers and light sources are reviewed as well as novel protocols to move beyond lesional treatment and address field therapy. Daylight PDT is emerging as an alternative to conventional office/hospital-based PDT that offers the advantage of much reduced pain. Although most studies have assessed efficacy of PDT in immune-competent patients, there is accumulating evidence for topical PDT being considered an option to assist in reducing the skin cancer burden in organ transplant recipients. The fluorescence associated with photosensitizer application can help delineate lesions prior to full treatment illumination and offers a useful adjunct to treatment in patients where diagnostic uncertainty or poor lesion outline complicates clinical care. PDT may also offer significant benefit in delaying/preventing new cancer development and combined with its recognized photo-rejuvenating effects, is emerging as an effective therapy capable of clearing certain superficial skin cancers, potentially preventing new lesions as well as facilitating photo-rejuvenating effects in treated areas.

Optimal management of skin cancer in immunosuppressed patients

Skin cancer is the most common malignancy in humans with basal cell carcinoma representing the majority of cases in the general population. The prevalence of skin cancer is increased amongst immunosuppressed patients such as those with lymphoproliferative disorders including non-Hodgkin lymphoma and chronic lymphocytic leukemia or those with iatrogenic immunosuppression following organ transplantation. In addition, these patients experience greater morbidity and mortality associated with skin cancers. The most common skin cancer in immunosuppressed patients is squamous cell carcinoma, which often presents with more aggressive features and has a greater rate of metastasis. This article reviews the risk factors, etiology, clinical presentation, and prevalence of skin cancer amongst immunosuppressed patients, including organ transplant, lymphoproliferative disorders, autoimmune disorders, and human immunodeficiency virus. We also provide a comprehensive review of treatment guidelines for immunosuppressed patients with cutaneous malignancy. Surgical therapy is the cornerstone of treatment; however, we also discuss pharmacologic treatment options, lifestyle modifications, and revision of immunosuppressive regimens.

Intensified fractional CO2 laser-assisted photodynamic therapy vs. laser alone for organ transplant recipients with multiple actinic keratoses and wart-like lesions: a randomized half-side comparative trial on dorsal hands

BACKGROUND

Photodynamic therapy (PDT) is a well-documented treatment for actinic keratosis (AK), but achieves inferior efficacy in organ transplant recipients (OTRs), particularly in acral regions. Ablative fractional laser (AFXL) intensifies the PDT response and may improve the efficacy of AK clearance when used as monotherapy.

OBJECTIVES

To compare the efficacy of a single treatment with AFXL-assisted PDT vs. AFXL alone for difficult-to-treat AKs and wart-like lesions (WLLs) in OTRs.

METHODS

Ten OTRs were included with a total of 680 AKs (severity grade I-III) and 409 WLLs on the dorsal hands. Both hands were initially treated with targeted fractional ablation of thick keratotic lesions followed by AFXL field treatment. Treatment regions were then randomized to (i) PDT (AFXL-PDT) or (ii) no further treatment (AFXL). The primary end point was complete response (CR) at 4 months after treatment; secondary end points were improvement of AK severity grade, overall patient assessment of efficacy and tolerability of treatments.

RESULTS

CR of AKs was significantly higher for AFXL-PDT (73%) compared with AFXL alone (31%) (P = 0·002). AFXL-PDT improved 82% of AKs to lower lesion grades compared with 52% after AFXL alone (P = 0.008). For WLLs, the rate of CR was 37% for AFXL-PDT compared with 14% for AFXL (P = 0·02). Overall assessment showed a preference for AFXL-PDT compared with AFXL (AFXL-PDT, n = 8; AFXL, n = 0; equal, n = 2). Mild pigment changes were observed in four patients (AFXL-PDT, n = 3; AFXL, n = 1). No scarring was observed.

CONCLUSIONS

AFXL-PDT is more effective than AFXL in the treatment of acral AKs and WLLs in OTRs.

[New developments in photodynamic therapy]

We review new developments in recent years in photodynamic therapy. Since 2009 two new photosensitizers, a self-adhesive 5-aminolevulinic acid (ALA) patch and a nanoemulsion formulation of 5-aminolevulinic acid have been approved for the treatment of actinic keratoses. Pretreatment with ablative fractional lasers enhances penetration of the photosensitizer and enables intensified PDT in acral lesions and in field-cancerized skin. Several clinical trials have demonstrated the skin-rejuvenating effects of photodynamic therapy, while the underlying mechanisms of action have been clarified. The efficacy of photodynamic therapy has been shown in the treatment and prophylaxis of actinic keratoses in organ transplant recipients at high risk for developing skin cancer. We also summarize the results of available studies on daylight-mediated photodynamic therapy.

Management of actinic keratosis

Actinic keratoses are common, often multiple, epidermal lesions found mainly on the sun-exposed skin of fair-skinned middle-aged and older people.(1) Over time, lesions may remain unchanged or may proliferate, regress, reappear or develop into squamous cell carcinoma (SCC).(2) Detectable (spot) lesions are often associated with alteration of the surrounding skin (field) where subclinical lesions might be present.(2) Interventions may target individual or multiple lesions or a whole field.(2) Here, we update our previous review(3) on the prevention and treatment of actinic keratoses, focusing on the licensed treatments most commonly used in the UK and recommended in UK guidelines.

Consensus recommendations for the treatment of basal cell carcinomas in Gorlin syndrome with topical methylaminolaevulinate-photodynamic therapy

BACKGROUND

Patients with Gorlin syndrome develop multiple basal cell carcinomas (BCC), for which treatment is often difficult. Methylaminolevulinate-photodynamic therapy (MAL-PDT) is approved for the treatment of superficial and nodular BCCs in Canada and several European countries.

OBJECTIVES

To establish consensus recommendations for the use of MAL-PDT in patients with Gorlin syndrome.

METHODS

The Gorlin consensus panel was comprised of 7 dermatologists who had treated a total of 83 patients with Gorlin syndrome using MAL-PDT. Consensus was developed based on the personal experience of the expert and results of literature review (on PUBMED using the keywords 'MAL' and 'PDT' and 'Gorlin' or 'naevoid basal cell carcinoma syndrome').

RESULTS

Consensus was reached among the experts and the literature review identified 9 relevant reports. The experts considered MAL-PDT a generally effective and safe therapy for treatment of BCC in Gorlin syndrome. For superficial BCC (sBCC), all sizes can be treated, and in nodular BCC (nBCC), better efficacy can be achieved in thinner lesions (<2 mm in thickness). MAL-PDT treatment schedule should be performed according to labelling although in individual cases, it may be adapted and performed on a monthly basis based on clinical assessment. Follow-up should be related to frequency of recurrence, and severity, number and location of lesions. Multiple lesions and large areas may be treated during the same session; however, adequate pain management should be considered.

CONCLUSIONS

MAL-PDT is safe and effective in patients with Gorlin syndrome. Utilization of these recommendations may improve efficacy and clearance rates in this population.

Management of non-melanoma skin cancer in immunocompromised solid organ transplant recipients

The management of non-melanoma skin cancers (NMSCs) in solid organ transplant recipients (OTRs) presents a variety of clinical challenges for physicians. OTRs are at a 65-fold increased risk for developing cutaneous squamous cell carcinomas (SCC), the most common NMSC that develops after transplantation. Risk factors contributing to the development of NMSCs in OTRs include a past medical history of any previous skin cancer, a personal history of significant sun exposure and a fair skin complexion or phototype. Further, greater immunosuppressive medication levels lead to an increased risk of NMSCs. Among immunosuppressants, specific older agents such as azathioprine and cyclosporine may increase the risk of developing NMSCs in contrast to newer agents such as sirolimus. Early skin biopsy and treatment of premalignant and malignant lesions are essential for treating these patients successfully. In this regard, the concept of field cancerization has been instructive in broadening treatments to include entire affected areas rather than individual lesions given that the areas with significant ultraviolet irradiation will continue to develop numerous individual precancerous and cancerous lesions. Field therapy with photodynamic therapy or topical 5-fluorouracil, imiquimod or diclofenac is often used in OTRs according to individual patient tolerability. Prompt excision or Mohs micrographic surgery is the standard of care of primary, uncomplicated squamous cell and basal cell carcinomas. For patients with in-transit or metastatic squamous cell carcinomas, adjuvant radiation, chemotherapy, and staging by sentinel lymph node dissection may be employed. For patients who develop numerous SCC per year, chemoprophylaxis can be effective in limiting the burden of disease. In consultation with the multidisciplinary transplant team, the immunosuppressive regimen can be revised to lower overall immunosuppression or altered to include newer drugs that have decreased oncogenic potential in OTRs. The greatest impact may be made by the prevention of NMSCs through simple, but rigorous, patient education on the benefits of UV protection, periodic self-skin examinations, and regular follow-ups. Accordingly, vitamin D and calcium supplementation should also be incorporated in transplant recipients. Management of OTRs requires patient education, frequent motivation for vigilance, regular follow-up, and interdisciplinary collaboration between transplant surgeons, nephrologists, hepatologists, cardiologists, transplant nurses, dermatologists, oncologists, pharmacists, and other relevant physicians ideally orchestrated by the essential transplant coordinators.