Conventional vs. daylight methyl aminolevulinate photodynamic therapy for actinic keratosis of the face and scalp: an intra-patient, prospective, comparison study in Italy

Pre-treatment with topical 5-fluorouracil increases the efficacy of daylight photodynamic therapy for actinic keratoses - A randomized controlled trial

BACKGROUND

Daylight photodynamic therapy (dPDT) and topical 5-fluorouracil (5-FU) are each effective treatments for thin grade I actinic keratosis (AKs), but less so for thicker grade II-III AKs. Prolonged topical treatment regimens can be associated with severe skin reactions and low compliance. This study compares the efficacy of sequential 4 % 5-FU and dPDT with dPDT monotherapy for multiple actinic keratoses.

METHODS

Sixty patients with a total of 1547 AKs (grade I: 1278; grade II: 246; grade III: 23) were treated in two symmetrical areas (mean size 75 cm2) of the face or scalp, which were randomized to (i) 4% 5-FU creme twice daily for 7 days before a single dPDT procedure and (ii) dPDT monotherapy. Daylight exposure was either outdoor or indoor daylight.

RESULTS

Twelve weeks after treatment 87 % of all AKs cleared after 5-FU+dPDT compared to 74 % after dPDT alone (p<0.0001). For grade II AKs, the lesion response rate increased from 55 % with dPDT monotherapy to 79 % after 5-FU+dPDT (p<0.0056). Moderate/severe erythema was seen in 88 % 5-FU+dPDT areas compared to 41 % of dPDT areas two days after dPDT. Twelve weeks after treatment 75 % of the patients were very satisfied with both treatments.

CONCLUSIONS

Sequential 5-FU and dPDT was more effective than dPDT monotherapy in the treatment of AKs, especially for grade II AKs. Local skin reactions were more pronounced after combination treatment, but no patients discontinued the treatment. The combination of 5-FU and dPDT is an effective treatment of large treatment areas with high compliance and satisfaction.

The impact of occlusive vs non-occlusive application of methyl aminolevulinate on the efficacy and tolerability of daylight photodynamic therapy for actinic keratosis

BACKGROUND

Conventional photodynamic therapy (c-PDT) is an effective treatment for actinic keratoses (AKs) and nonmelanoma skin cancer which exploits the photosensitizing properties of methyl aminolaevulinate (MAL). Daylight photodynamic therapy (DL-PDT) is an alternative to c-PDT which does not require the application of MAL in occlusion and that is better tolerated by patients. The impact of occlusion on the efficacy of DL-PD has not been investigated by previous studies.

OBJECTIVE

To compare the efficacy and tolerability of occlusive and non-occlusive DL-PDT.

METHODS

We conducted a prospective intraindividual left/right comparison study. AKs of the face or scalp were marked in two symmetrical treatment areas. The two target areas were randomly assigned to DL-PDT with occlusive and non-occlusive application of MAL. The efficacy and cosmetic outcome were determined by a "blinded" investigator.

RESULTS

Lesions in occluded areas showed a better response in the clearance rate of the lesions (65.5% vs 35.0 %, p < 0.001 %), and cosmetic outcome (P < 0.001). There was no difference in phototoxicity or pain between occluded and non-occluded areas.

CONCLUSION

The occlusive application of MAL improves the efficacy of DL-PDT in clearing AKs and does not increase the incidence of side effects.

Methyl Aminolaevulinic Acid versus Aminolaevulinic Acid Photodynamic Therapy of Actinic Keratosis with Low Doses of Red-Light LED Illumination: Results of Long-Term Follow-Up

Photodynamic therapy (PDT) treatment for multiple actinic keratosis (AK) has been found effective when lower doses of red light were used with methyl aminolaevulinic acid (MAL). The aim of this study was to compare the results of lower doses of red light conventional PDT (h-PDT, 16 J/cm2) with MAL and aminolaevulinic acid (ALA) in a long-term follow-up. Patients with more than five symmetrical AK on the scalp who were candidates for PDT were selected and divided randomly between MAL and ALA treatment and patients were followed at 3 and 12 months. The responses were assessed by counting the total AK and the AK per patient. Pain and adverse events were also compiled. A total of 46 patients were treated, 24 with MAL, and 22 with ALA. The two groups were comparable at baseline (p > 0.005). No significant differences were found in the results of both treatments at 12 months, despite ALA exhibiting slightly better results at 3 months. No differences in pain and adverse events were assessed. Both ALA and MAL were effective when lower doses of red light were used in c-PDT. Long term efficacy was also documented. Further studies are necessary to determine the inferior point of red-light illumination without losing efficacy.

Efficacy of two different methods of cold air analgesia for pain relief in PDT of actinic keratoses of the head region - a randomized controlled comparison study

BACKGROUND

Photodynamic therapy (PDT) is an effective method for treating actinic keratosis (AK) with pain during illumination representing the major side effect. The efficacy of two different cooling methods for pain relief in PDT of AK in the head region was compared.

METHODS

Randomized, assessor-blinded, half side comparison study in 20 patients with symmetrically distributed AK on the head. Conventional PDT was performed on both halves of the scalp or face by applying 20% aminolevulinic acid cream (ALA) and subsequent illumination with incoherent red light. During illumination one side was cooled with a cold air blower (CAB) and the other with a standard fan (FAN) in a randomized fashion. Pain and skin temperature were recorded during and after PDT. The phototoxic skin reaction was evaluated up to seven days after PDT. The clearance rate of AK was assessed at 3 and 6 months after PDT.

RESULTS

Mean pain (VASmean), maximum pain intensity (VASmax) and the mean skin temperature during PDT were significantly lower with CAB as compared to FAN (VASmean: 2.7 ± 1.4 vs. 3.7 ± 2.1, p = 0.003; VASmax: 3.8 ± 2.0 vs. 4.8 ± 2.5, p = 0.002; 26.8 ± 2.0 °C vs. 32.1 ± 1.7 °C; p=<0.001). The severity of the phototoxic skin reaction and the clearance rate of AK did not differ between the two cooling methods.

CONCLUSION

Cooling with CAB during PDT has a greater analgesic effect than cooling with FAN. Patients with a lower skin temperature during illumination tended to experience less pain, however, this effect did not reach the level of statistical significance.

Combined versus conventional photodynamic therapy with 5-aminolaevulinic acid nanoemulsion (BF-200 ALA) for actinic keratosis: A randomized, single-blind, prospective study

BACKGROUND

Photodynamic therapy (PDT) has become one of the most effective therapies for the treatment of actinic keratosis, allowing the removal of more than one lesion in a single session. However, the pain sustained by the patient during treatment and local skin reactions can limit its use.

OBJECTIVES

To determine the efficacy and safety of combined PDT (daylight PDT followed by conventional PDT) vs conventional PDT 12 weeks after treatment.

METHODS

The study was performed as a randomized, single-center, non-inferiority clinical trial with two parallel groups. A total of 51 patients with grade I and II AKs on the scalp or face were randomized. Twenty-five patients received one session of combined PDT (combPDT), and 26 patients received one session of conventional PDT (cPDT). The primary endpoint was the reduction of AKs, 12 weeks after treatment. The secondary endpoint was the reduction in pain and local skin reaction.

RESULTS

The reduction rate of grade I and II AKs was similar in combPDT and cPDT, showing no statistically significant differences between both groups, 76.67% vs 86.63% [P = .094] and 80.48% vs 83.08% [P = .679], respectively. However, pain was significantly lower in the combPDT group (2.56 vs 5, P < .01), as were local skin reactions.

CONCLUSIONS

CombPDT has proven to be as effective as cPDT for the treatment of grade I and II AKs located on the scalp and face. Furthermore, combPDT has been shown to be considerably more tolerable than cPDT, causing only mild local skin reactions.

Review of the European Society for Photodynamic Therapy (Euro-PDT) Annual Congress 2020

This article reviews the 2020 European Society for Photodynamic Therapy (Euro-PDT) Annual Congress. Cutting edge studies included assessment of immunohistochemical variables influencing response of basal cell carcinomas and Bowen's disease to PDT with p53, the only biomarker associated with good response in both conditions. A further study indicated that analysis of molecular markers, such as PIK3R1, could help select patients with actinic keratoses who demonstrate the best response to daylight PDT. Novel delivery protocols include artificial daylight, and laser-assisted and textile PDT. The meeting learnt of novel indications including antimicrobial PDT, as well as methods to optimise daylight PDT, including combination therapy for actinic keratoses. Adverse events were reviewed and options for painless and efficient PDT assessed, including the effect of reduced drug-light interval. A smartphone application was also evaluated which may be used to assist clinicians and patients in effective dosing and timing of daylight PDT via computational algorithms using data from earth observation satellites, to send light and ultraviolet dose information directly to patients' smart phones.

5-Aminolaevulinic acid patch photodynamic therapy for the treatment of actinic keratoses: preliminary results from an Italian study in the real-life setting

BACKGROUND

Photodynamic therapy (PDT) is recommended for both lesion and field therapy of actinic keratoses (AKs). The 5-aminolaevulinic acid (5-ALA) patch PDT is indicated for the treatment of isolated mild AKs (≤1.8 cm) on the face and bald scalp. It was demonstrated to be effective and safe in clinical trials with a good tolerability profile.

METHODS

In this retrospective multicenter real-life study, 33 patients with a total of 99 AKs of the scalp, face, ears, and/or hands and 2 actinic cheilitis were treated with one treatment session of 5-ALA patch PDT with a red light source (total dose of 37 J/cm2).

RESULTS

Overall, 12 weeks after treatment, 68/99 (69%) lesions were completely cleared. Complete response was obtained in 82% of AKs on the ears, 78% on the face, 57% on the hands, and 56% on the scalp and in the two actinic cheilitis. The treatment was very effective on grade I AKs, cleared in 87% of the cases and less efficient on grade II-III lesions, cleared in 47% of the cases. 5-ALA patch PDT was well tolerated with a good to excellent cosmetic outcome in 97% of the patients and with 94% of the patients being satisfied or very satisfied with the treatment.

CONCLUSIONS

Our results confirm that 5-ALA patch PDT is a good option for AK treatment in clinical practice, it is easy to use, effective and well tolerated even in difficult-to-treat-areas. Moreover, it has an excellent cosmetic outcome.

Field cancerization: Treatment

The goal of field cancerization treatment is to reduce the risk of developing keratinocyte carcinoma. Selecting the appropriate therapy depends on the degree of field cancerization and the number of invasive cutaneous squamous cell carcinomas. Other considerations include treatment efficacy, cost, side effects, and patient preference. Field therapies are preferred because they address clinically visible disease and subclinical atypia. However, lesion-directed therapies are useful for lesions that are more difficult to treat or those where a histologic diagnosis is required. Patients with extensive field cancerization benefit from a combination of field-directed and lesion-directed treatments. The second article in this continuing medical education series provides a framework to guide evidence-based decision making for field cancerization treatment.

A feasibility study of microwave therapy for precancerous actinic keratosis

BACKGROUND

Actinic keratosis (AK) is a common premalignant skin lesion that can progress to cutaneous squamous cell carcinoma (cSCC). Microwave therapy is an established cancer treatment and has been used for plantar viral warts.

OBJECTIVES

To evaluate the efficacy and feasibility of microwave as a treatment for AK.

METHODS

Stage I was a dose-setting study, in which seven participants had the dielectric properties of 12 thick and 22 thin AKs assessed for optimization of the microwave dose used for treatment in Stage II. Stage II was a randomized, internally controlled trial evaluating 179 AKs in 11 patients (93 treated, 86 untreated controls) on the scalp/forehead or dorsal hand. Participants received one treatment initially and a repeat treatment to unresolved AKs at week 4. The response was assessed at six visits over 4 months. The primary outcome was partial or complete resolution of the treated AKs.

RESULTS

A significantly higher proportion of treated AK areas responded than untreated (90% vs. 15%; P < 0·001). Thin AKs were more responsive than thick AKs. The site did not affect efficacy. Pain was severe, but brief (80% reported pain lasting 'a few seconds only'). Adverse effects were minimal (erythema, n = 6; flaking, n = 3; itch, n = 3). All participants who would chose microwave therapy over their current treatment cited the shorter discomfort period.

CONCLUSIONS

Microwave therapy is a portable, safe and effective treatment for AK. An easy-to-deliver, acceptable therapy for AK is attractive as a prevention strategy. While these results are promising, a larger randomized controlled trial is needed against an effective comparator to confirm clinical efficacy and patient acceptability. What is already known about this topic? Actinic keratoses (AKs) are common precancerous skin lesions. Successful treatment of AK can prevent cutaneous squamous cell carcinoma (cSCC). Most topical therapies for AK require repeated application over weeks and drive local skin inflammation, leading to poor compliance. An easy-to-deliver and effective treatment for AK, suitable for use in primary care, could reduce cSCC. What does this study add? Microwave therapy is a feasible, effective treatment for AK. Ninety per cent of treated AKs showed full or partial resolution at 120 days post-treatment. Microwave therapy was painful, but the pain was short-lived (seconds) and this short discomfort period was cited as the main reason that microwave was preferred to their current treatment.

Daylight photodynamic therapy with methyl aminolevulinate cream is as effective as conventional photodynamic therapy with blue light in the treatment of actinic keratosis: a controlled randomized intra-individual study

BACKGROUND

We know the efficacy of daylight phototherapy dynamic (DL-PDT) in the treatment of actinic keratosis (AK). But the almost studies have compared daylight with red light using methyl aminolevulinate cream and not with blue light. PDT with blue light is another conventional PDT that is effective in the treatment of AKs.

OBJECTIVES

The aim of this study is to assess the efficacy and the safety of DL-PDT vs. PDT in blue light in the treatment of AKs.

METHODS

This randomized, controlled, intra-individual efficacy and safety study enrolled 26 subjects. AKs on the face/scalp were treated once, with DL-PDT on one side and c-PDT on the contralateral side. Primary endpoints for DL-PDT at week 12 were efficacy with clearance of AKs and safety with assessment of pain. Lesions with complete response 12 weeks after one treatment session were followed until week 24.

RESULTS

More than 1000 AK were studied. At week 12, the raw number of disappeared AK lesions at 3-month follow-up was 19.6 (±6.0) for DL-PDT and 20.0 (±6.9) for c-PDT with P = 0.8460 (90.5% vs. 94.2% of AK disappearance, respectively). The response was maintained at 6 months (90.0% and 94.6% of AK reduction, respectively). DL-PDT was nearly painless than c-PDT with light blue: 1.2 vs. 5.1, respectively (P < 0.0001).

CONCLUSIONS

Daylight-PDT seems as effective as c-PDT with light blue and DL-PDT is less painful. The response of DL-PDT was sustainable until 6 months.

Updates on Treatment Approaches for Cutaneous Field Cancerization

Purpose of Review

Field cancerization describes the phenomenon that multiple heterogenous mutations may arise in an area exposed to chronic carcinogenic stimuli. Advances in the understanding of cutaneous field cancerization have led to novel therapeutic approaches to the management of actinic keratoses (AKs). Herein, we review the literature on the pathophysiology and emerging research of field cancerization in dermatology.

Recent Findings

The classification systems for grading AK lesions are being refined with investigations focusing on their clinical utility. There is a growing shift towards field-directed treatment for AKs as the importance of field cancerization becomes clearer. Current field-directed therapies are being optimized and novel therapeutic modalities are being studied.

Summary

Field cancerization underlies the transformation of photodamaged skin into AKs and potentially cutaneous SCC (cSCC). Clinically meaningful classification systems for AKs are needed to better inform decisions regarding treatment. As we learn more about the role of field characterization in photodamage, AKs and cSCCs, therapeutic strategies are becoming more field-directed rather than lesion-directed.

Photodynamic therapy: A hot topic in dermato-oncology

Photodynamic therapy (PDT) is a modern, non-invasive therapeutic method used for the destruction of various cells and tissues. It requires the simultaneous presence of three components: a photosensitizer (PS), a light source and oxygen. Precancerous skin lesions are conditions associated with a high likelihood of malignant transformation to squamous cell carcinoma. Data available so far indicate that PDT is a promising treatment method which can be successfully employed in several medical fields including dermatology, urology, ophthalmology, pneumology, cardiology, dentistry and immunology. Numerous authors therefore have studied this technique in order to improve its efficacy. As a result, significant advancement has been achieved with regard to PSs and drug delivery systems. Substantial progress was also obtained with respect to PDT for the treatment of precancerous skin lesions, several authors focusing their efforts on the study of daylight-PDT and on identifying methods of decreasing technique-related pain. This review reports on the most recent findings in PDT, with emphasis on cutaneous precancerous lesions.

Prevalence, Discontinuation Rate, and Risk Factors for Severe Local Site Reactions with Topical Field Treatment Options for Actinic Keratosis of the Face and Scalp

Actinic keratoses (AKs) are common lesions on chronically sun damaged skin, which are morphologically characterized by lower third to full thickness atypia of epidermal keratinocytes. These lesions carry a risk of progression towards invasive squamous cell carcinoma (SCC); therefore, treatment of visible lesions and the field in case of field cancerization is recommended. Treatment of AK includes the destruction of atypical keratinocytes that clinically presents with various degrees of erythema, scaling, crusting, erosion, and other visible and subjective symptoms. Such inflammatory reactions may have an impact on the patient’s social life and have shown to decrease compliance and adherence to therapy. Additionally, as various topical treatments have been proven to be effective in treating AK, tolerability of local site reactions (LSRs) might drive the decision for appropriate treatment in an individual scenario. Therefore, we aimed to review prevalence of severe LSRs among various topical treatments for AK. In addition, we summarized discontinuation rates due to LSRs and possible therapy-unrelated risk factors for the development of LSRs with increased severity.

Efficacy of different photoprotection strategies in preventing actinic keratosis new lesions after photodynamic therapy. The ATHENA study: a two-center, randomized, prospective, assessor-blinded pragmatic trial

Background: Treatment of actinic keratosis (AK) and field cancerization with photodynamic therapy (PDT) is an effective therapeutic approach with a significant reduction in the number of AK lesions (-75% or more) associated with a significant cosmetic improvement of the photodamaged skin. Recently, also, the daylight PDT (DL-PDT) has proven to be as effective as the conventional PDT (C-PDT), but with a better tolerability. After C-PDT and DL-PDT it is advised to use photoprotection strategies to improve the clinical evolution and prevent the appearance of new AK lesions that usually appear 3-6 months after the last phototherapy session. However, there are no robust clinical data regarding the type of photoprotection to be used (SPF level, duration of treatment, etc.) after successful PDT.Study aim: The present study (ATHENA trial) evaluated the efficacy and tolerability of a topical product based on 0.8% piroxicam and 50+ solar filters (ACTX), applied twice a day as sequential therapy after C-PDT or DL-PDT on the evolution of AK lesions number compared to the use of very high photoprotection products commonly used in this clinical setting (SPF50+ or SPF100+ associated with photolyase) (Standard Sunscreens: SS group). Subjects and methods: This was a multicenter, randomized, two-arm, prospective controlled, assessor-masked outcome evaluation, parallel group (1:1), pragmatic study of 6 months duration in patients with multiple AK lesions suitable for photodynamic therapy. The objectives of the study were the evaluation of the evolution of the number of AK lesions during the period of treatment/application of the study products, and the Investigator global clinical assessment score (IGA score; 4: marked improvement, 3: good, 2: moderate; 1 no improvement; 0: worsening) 2, 3, and 6 months after the last PDT session. A total of 68 subjects (50 men, 18 women; mean age 70 years), 34 assigned to treatment with ACTX and 34 to treatment with SS (17 treated with a SPF50+ and 17 with a photolyase-containing SPF100+ products), were enrolled in the study.Results: The number of AK lesions present before C-PDT/DL-PDT was 11.8 ± 5.8 in the ACTX group and 12.4 ± 6.9 in the SS group. In both groups, there was a progressive reduction of AK lesions observed at baseline (-86% and -87% after 2 months and -88% and -83% at month 3 in ACTX and in the SS group, respectively). At month 6, AK mean lesion number was 1.8 ± 1.6 in the ACTX and 3.2 ± 2.3 in the SS group; this difference was statistically significant (p = 0.03). The IGA score at the end of the study was 3.2 in the ACTX and 2.7 in the SS group (p = 0.05). The percentage of subjects with an IGA score of 4/3 (very good or good) was 81% in the ACTX and 55% in the SS group (p = 0.06).Conclusion: In subjects with AK treated with C-PDT or DL-PDT, a "medicalized" photoprotection treatment is associated with a favorable clinical outcome with progressive reduction of lesions. In contrast to a very high photoprotection (SPF50+ or SPF100+/photolyase), the use of piroxicam 0.8%/SPF 50+ is associated with a significantly greater improvement in clinical evolution of AK lesions.

Low-level light-assisted photodynamic therapy using a wearable cap-like device for the treatment of actinic keratosis of the scalp

BACKGROUND

Daylight photodynamic therapy (dlPDT) is a painless and increasingly cost-effective treatment for actinic keratosis (AK). New protocols avoid incubation, minimizing pain and adverse events. However, it is time-consuming and dependent on specific weather conditions. In patients with AK of the scalp, we evaluated the efficacy of indoor photodynamic therapy (PDT) using a wearable low-level light therapy (LLLT) device, without pre-incubation with a photosensitizing agent.

METHODS

In this pilot study, 27 patients with thin and moderately thick AK (Olsen Grades I-II) underwent a single 15-minute session of LLLT using a wearable cap-like device immediately after application of methyl-aminolevulinate (MAL) cream, with no prior preparation of the affected area. Treatment efficacy was quantified by measuring the reduction in AK lesion number and the AK quality of life (AKQoL) score. All AK lesions were mapped at baseline for follow-up 2 months later. Paired pre/post scalp biopsies from 5 patients were analysed using histological and immunohistochemical techniques (p53, p27, cyclin D1, p63, and Ki67 expression). Data were analysed using the Wilcoxon signed-rank test.

RESULTS

In all patients we observed a global reduction in the number of AK lesions (71%; p < 0.0001) and AKQoL score (from 5.6 to 4.4; p = 0.034) 2 months after treatment. Histology and immunohistochemistry of skin biopsies from 5 patients also revealed marked improvements after LLLT. No patients reported any pain during treatment.

CONCLUSION

PDT using LLLT is a rapid, painless, and efficacious modality for the treatment of AK.

New developments in the treatment of basal cell carcinoma: update on current and emerging treatment options with a focus on vismodegib

Basal cell carcinoma (BCC) is the most common form of skin cancer worldwide. Although most BCCs can be treated by relatively simple surgical or nonsurgical methods, some patients with BCC may eventually develop advanced disease which can either be locally destructive or even include metastatic spread. The present review summarizes the current literature on the treatment of both early and advanced BCC with a focus on the hedgehog inhibitor vismodegib which has become an integral part of the management of patients with advanced BCC since its regulatory approval in 2012.

Current developments in pharmacotherapy for actinic keratosis

INTRODUCTION

Actinic keratosis (AK) is a superficial squamous cell carcinoma (SCC) where chronic sun exposure playing central role in its pathogenesis. UVB causes direct damage to DNA, producing pyrimidine dimers, and suppressing the protective role of p53. The stepwise progression of AK, with increased expression of anti-apoptotic Bcl-2, favors progression to SCC. Moreover, the dermal response characterized by inflammation and mediated by prostaglandins is a critical component of tumorigenesis that promotes tumor growth, tissue invasion, angiogenesis and metastasis. Other risk factors are represented by age, gender, phototype and drugs.

AREAS COVERED

In this review, the authors document the recent developments of different therapies used to treat AK and provide their perspectives on current and future treatment strategies.

EXPERT OPINION

The usefulness of long-term treatment with piroxicam and sun filters or diclofenac targeting the inflammation phases of skin tumorigenesis favors AK's healing and provides greater control of the cancerization field. Nonsteroidal anti-inflammatory drugs can be safely used in patients who use photosensitizing drugs and, therefore, are more at risk of developing skin tumors. Immunomodulatory therapies, which require shorter treatment, are characterized by more common local side effects, and need more attention by the dermatologist in the concern of patient education, resulting essential to improve adherence and outcomes.

Daylight Photodynamic Therapy for Actinic Keratoses

Topical photodynamic therapy (PDT) using daylight is effective in the treatment of actinic keratoses (AKs), offering the potential for treatment of large fields such as full face and balding scalp, but with minimal therapy-associated pain. Comparison with conventional PDT indicates similar efficacy for thin and moderate-thickness AKs, but with significantly less discomfort/pain, driving a patient preference for daylight-mediated PDT (DL-PDT) compared with conventional PDT using high-intensity office/hospital-based light sources. Treatment protocol involves the application of a photosensitizing agent without occlusion and subsequent exposure to ambient daylight within 30 min, with patients exposed to daylight for 1.5-2.0 h. Pivotal randomized controlled trials in Europe and Australia have confirmed the efficacy of methyl aminolevulinic acid (MAL) DL-PDT in comparison with conventional MAL-PDT for mild and moderate-thickness lesions on the face and scalp. Initial clearance rates of 70-89% are reported. DL-PDT using a nanoemulsion aminolevulinic acid (ALA) has recently been shown to be at least as effective as MAL DL-PDT in treating mild and moderate-thickness AKs. DL-PDT may offer a better-tolerated method for treating patients with extensive AK disease. There is emerging literature on the potential for field PDT to reduce the number of new AKs developing, potentially preventing/slowing skin cancer development. Conventional PDT remains established as a therapy for Bowen's disease (squamous cell carcinoma in situ), superficial and certain thin basal cell carcinomas (BCCs), and AKs. The evidence for the use of DL-PDT beyond AK is limited, although has been reported in actinic cheilitis, superficial BCC, and acne and cutaneous leishmaniasis. There is emerging interest in combination therapy for AK, using one or more field therapies such as DL-PDT as an option to complement with localized treatment for residual lesions. We review current recommendations and consider the appropriate place for DL-PDT in our treatment armamentarium.

The safety and efficacy of daylight photodynamic therapy in the treatment of actinic keratoses: a systematic review and meta-analysis

Daylight photodynamic therapy (DLPDT) is a novel therapeutic approach for actinic keratoses (AKs). This study aimed to evaluate the safety and efficacy of DLPDT in treating patients with AKs as compared to conventional photodynamic therapy (CPDT). PubMed, EMBASE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for relevant randomized controlled trials (RCTs) published before November 2017, based on the following search terms: "solar keratoses", "actinic keratoses", "photodynamic therapy", "daylight photodynamic therapy", "conventional photodynamic therapy", and "randomized". The complete response rate, patient satisfaction, and patient-reported pain after intervention with DLPDT or CPDT were primarily measured. Sensitivity analysis was conducted to determine the reliability of results. Begg's and Egger's tests were used to assess the likelihood of publication bias. Eight RCTs, comprising a total of 424 patients with AKs treated with DLPDT or CPDT, were included. No significant difference was found between the lesion response rate and the mean lesion response in a comparison of DLPDT and CPDT treatments. Generally, DLPDT was associated with higher patient satisfaction than CPDT. The patients who underwent DLPDT experienced less pain than those who underwent CPDT. Most of our results were of high stability and low sensitivity. Meanwhile, no statistical evidence of publication bias among studies was found under all comparisons. In conclusion, DLPDT is a safe and effective therapy, which could help in selecting the most appropriate therapeutic method for treating AKs and in guiding physicians to optimize treatment strategies.

Field Cancerization Therapies for Management of Actinic Keratosis: A Narrative Review

Actinic keratoses (AKs) are atypical, precancerous proliferations of keratinocytes that develop because of chronic exposure to ultraviolet (UV) radiation. Treatment of AK can be lesion-directed or field-directed. Field cancerization theory postulates that the skin surrounding AK is also at increased risk for possible malignant transformation since it has been exposed to the same chronic UV light. Field-directed therapies thus have the potential to address subclinical damage, reduce AK recurrence rates, and potentially reduce the risk of squamous cell carcinoma (SCC) development. Published clinical studies have found lesion clearance rates ranging from 81 to 91% for photodynamic therapy (PDT) with either aminolevulinic acid (ALA) or methylaminolevulinate (MAL). Clinical studies have also been published on various topical treatments. Complete clinical clearance (CCC) was significantly higher in patients treated with a combination of 5-fluorouracil and salicylic acid (5-FU-SA) than in the vehicle group across multiple studies, and CCC ranged between 46 and 48% following treatment with imiquimod. Additionally, treatment with diclofenac sodium (DFS) found reduction in lesion sizes to range from 67 to 75%. Reported results have been similar for another non-steroidal anti-inflammatory drug (NSAID), piroxicam, which has more cyclooxygenase (COX)-1 activity than DFS. Active treatments with ingenol mebutate were also significantly more effective than vehicle at clearing AK lesions. All treatments resulted in mild, localized skin reactions. PDT using conventional light sources was associated with increased severity of pain and/or discomfort, while PDT using daylight as the light source was associated with less pain and occasionally no pain at all. Though no widely accepted algorithm for the treatment of AKs exists, field-directed therapy can be particularly useful for treating photo-exposed areas containing multiple AKs. Additional research with more direct comparisons between these field-directed therapies will help clinicians determine the best therapeutic approach. Here, we provide a balanced and comprehensive narrative review of the literature, considering both light-based and topical therapies with a focus on their field-therapy aspects, and propose a therapeutic algorithm for selecting an appropriate treatment in the clinical setting.

A novel light source with tuneable uniformity of light distribution for artificial daylight photodynamic therapy

OBJECTIVES

Implementation of daylight photodynamic therapy (dPDT) is somewhat limited by variable weather conditions. Light sources have been employed to provide artificial dPDT indoors, with low irradiances and comparable treatment times to dPDT. Uniform light distribution across the target area is desirable in effective treatment planning, particularly for large areas. A novel light source is developed with tuneable direction of light emission in order to meet this challenge.

METHODS

Wavelength composition of the novel light source is controlled such that the protoporphyrin-IX (PpIX) weighted spectra of both the light source and daylight match. The uniformity of the light distribution is characterised on a flat surface, a model head and a model leg. For context, a typical conventional PDT light source is also characterised. Additionally, the wavelength uniformity across the treatment site is characterised.

RESULTS

The PpIX-weighted spectrum of the novel light source matches the PpIX-weighted daylight spectrum, with irradiance values within the bounds for effective dPDT. By tuning the direction of light emission, improvements are seen in the uniformity across large anatomical surfaces. Wavelength uniformity is discussed.

CONCLUSIONS

We have developed a light source that addresses the challenges in uniform, multiwavelength light distribution for large area artificial dPDT across curved anatomical surfaces.

Long-term efficacy data for daylight-PDT

INTRODUCTION

Conventional photodynamic therapy (c-PDT) is an established successful treatment for non-melanoma skin cancers (NMSC). Daylight PDT (DL-PDT) was introduced to overcome the main inconveniencies associated with c-PDT such as pain during illumination and long clinic visits. DL-PDT was shown to have similar short-term efficacy to c-PDT for the treatment of mild/moderate actinic keratosis (AKs) but it is associated with better tolerability. Since AKs tend to regress and reoccur over time, data on long-term efficacy of DL-PDT become crucial.

EVIDENCE ACQUISITION

We performed a systematic review search up to February 2018 of available studies on DL-PDT long-term efficacy using the MEDLINE database and made a manual search of selected references.

EVIDENCE SYNTHESIS

Most current studies on DL-PDT have limited follow-up periods of 3 to 6 months. Only 2 randomized, intra-individual studies provided efficacy data on AK treatment at 12 month-follow-up and supported the long-term efficacy of this novel treatment modality showing a low recurrence rate, varying from 8.7% to 13%. Current evidences for other NMSCs are limited and efficacy seems to be not as good as for AK.

CONCLUSIONS

DL-PDT is a very promising treatment for mild to moderate AKs of the face and scalp. Efficacy outcomes of DL-PDT are similar to those of c-PDT in the short-term. Additional studies are required to increase our knowledge on DL-PDT long-term efficacy, as limited data are currently available.

Quantifying the radiant exposure and effective dose in patients treated for actinic keratoses with topical photodynamic therapy using daylight and LED white light

Daylight photodynamic therapy (dl-PDT) is as effective as conventional PDT (c-PDT) for treating actinic keratoses but has the advantage of reducing patient discomfort significantly. Topical dl-PDT and white light-PDT (wl-PDT) differ from c-PDT by way of light sources and methodology. We measured the variables associated with light dose delivery to skin surface and influence of geometry using a radiometer, a spectral radiometer and an illuminance meter. The associated errors of the measurement methods were assessed. The spectral and spatial distribution of the radiant energy from the LED white light source was evaluated in order to define the maximum treatment area, setup and treatment protocol for wl-PDT. We compared the data with two red LED light sources we use for c-PDT. The calculated effective light dose is the product of the normalised absorption spectrum of the photosensitizer, protoporphyrin IX (PpIX), the irradiance spectrum and the treatment time. The effective light dose from daylight ranged from 3  ±  0.4 to 44  ±  6 J cm^-2due to varying weather conditions. The effective light dose for wl-PDT was reproducible for treatments but it varied across the treatment area between 4  ±  0.1 J cm^-2 at the edge and 9  ±  0.1 J cm^-2 centrally. The effective light dose for the red waveband (615-645 nm) was 0.42  ±  0.05 J cm^-2 on a clear day, 0.05  ±  0.01 J cm^-2 on an overcast day and 0.9  ±  0.01 J cm^-2 using the white light. This compares with 0.95  ±  0.01 and 0.84  ±  0.01 J cm^-2 for c-PDT devices. Estimated errors associated with indirect determination of daylight effective light dose were very significant, particularly for effective light doses less than 5 J cm^-2 (up to 83% for irradiance calculations). The primary source of error is in establishment of the relationship between irradiance or illuminance and effective dose. Use of the O'Mahoney model is recommended using a calibrated logging illuminance meter with the detector in the plane of the treatment area.

Daylight photodynamic therapy: experience in the treatment of actinic keratosis in the San Gallicano Institute (Rome) and a review of literature

BACKGROUND

Actinic keratosis (AK) is a photo-induced skin lesion. It has been considered by several authors as in-situ squamous cell carcinoma (SCC), that can evolve to invasive SCC (iSCC). Given the malignant potential and because it is impossible predict which AK will evolve in iSCC, it is necessary to treat each lesion. Multiple therapeutic approaches have been described to treat AKs. In addition to the topical drugs, photodynamic therapy (PDT) has become an established therapeutic modality for grade I and II of AKs of face and scalp. Recently the daylight photo-dynamic therapy (DL-PDT) has found extensive use in the care of the AK and in the field cancerization.

METHODS

The study included 101 patients, 90 males and 11 females, mean age 71, phototype I-II, with multiple AK I and II of the face and the scalp, treated with DL-PDT. Patients were clinically evaluated for 3 months. The aim of this study was to show our experience in Daylight Photodynamic Therapy, to confirm the validity in term of efficacy and safety of DL-PDT for I and II AK of face and scalp and to underline the patient's higher satisfaction for this type of treatment and his availability to be retreated with the DL-PDT.

RESULTS

The efficacy was complete in 16 patients (15.8%), in 71 patients (70.3%) was much improved or improved and only in 14 (13.9%) subjects were minimal, while nobody had worsened or changed. The majority of patients (84.2%) patients were satisfied of the efficacy as well of the cosmetic results, only 15 (14.9%) were low satisfied and one patient was not satisfied.

CONCLUSIONS

This study confirms that the DL-PDT is a good alternative to c-PDT for the treatment of grade I and II AK of the face and scalp and in Rome, as in Southern Europe, it is possible to perform the DL-PDT in almost every month of year.

Daylight-Mediated Photodynamic Therapy With Methyl Aminolevulinate in Actinic Keratosis Treatment

BACKGROUND

Research has shown daylight-mediated photodynamic therapy (PDT) for the treatment of actinic keratosis (AK) to be effective, tolerable, and convenient, with excellent patient satisfaction and cosmesis. Although success has been demonstrated in areas with similar latitudes to Switzerland and Scandinavia, this treatment has not been studied in a Canadian population.

OBJECTIVES

The purpose of this study is to investigate the effectiveness, safety, and patient satisfaction of daylight-mediated methyl 5-aminolevulinate (MAL)-PDT to make recommendations for its use in Canadian practice.

METHODS

A retrospective chart review of patients who received treatment of daylight-mediated MAL-PDT for the indication of AK at the Institute of Cosmetic and Laser Surgery in Oakville, Ontario, between 2009 and 2016.

RESULTS

A total of 112 patients were included, consisting of 94 males and 18 females with a mean age of 63.79 years. A total of 177 sites were treated among all patients, mostly consisting of the face (n = 92) and scalp (n = 55). A total of 13.4% of patients experienced side effects, the most common being redness (n = 4) and scabbing (n = 4). Of the 42 patients who expressed their level of satisfaction, 83.3% reported being happy with the treatment, χ²(1) = 18.67, P ≤ .05; 6.3% of patients were noted to be completely clear, 86.6% had a good response, 0.9% had a mild response, and 0% had no response, χ²(1) = 101.04, P ≤ .05.

CONCLUSIONS

Daylight-mediated MAL-PDT is a suitable treatment option for AK lesions in a Canadian population due to the demonstrated efficacy, patient satisfaction, tolerability, and convenience.

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.

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.

[Procedure for daylight methyl aminolevulinate photodynamic therapy to treat actinic keratoses]

Actinic keratosis (AK), also known as solar keratosis or pre-cancerous keratosis, is frequently observed in areas of skin exposed to sunlight, particularly in light-skinned patients. In France, photodynamic therapy using red light (conventional PDT) and methylamino 5-levulinate (MAL) is indicated in the treatment of thin or non-hyperkeratotic and non-pigmented multiple AK lesions or large zones covered with AK lesions. It is well-known for its efficacy but also for its side effects, especially pain during illumination, which can limit its use. An alternative to PDT using natural daylight has recently been proposed to treat actinic keratosis lesions, and results in greater flexibility as well as significant reduction in pain. The lesions are prepared as for conventional PDT, with MAL cream being applied by the physician or the patient, after which they are exposed to natural daylight for 2hours. The lesions are then gently cleansed and protected from natural light for 24hours. This paper seeks to provide a precise description of the daylight PDT procedure for the treatment of AK.

Pulse photodynamic therapy reduces inflammation without compromising efficacy in the treatment of multiple mild actinic keratoses of the face and scalp: a randomized clinical trial

BACKGROUND

The main side-effects of photodynamic therapy (PDT) for actinic keratoses (AKs) are post-treatment erythema and oedema, and pain during illumination. Severe erythema after PDT enhances the down time associated with the treatment.

OBJECTIVES

To evaluate in a randomized intraindividual study whether pulse-PDT and corticosteroid pulse-PDT would reduce treatment-induced erythema compared with conventional PDT.

METHODS

Twenty-two patients with multiple mild AKs on the face and scalp were treated with methyl aminolaevulinate (MAL)-PDT in three similar areas. Two areas were incubated with MAL for 30 min (pulse-PDT) and one area was incubated with MAL for 3 h (conventional PDT). All areas were illuminated with red light after 3 h. In one of the pulse-PDT areas a superpotent corticosteroid was applied before and just after PDT (S-pulse-PDT).

RESULTS

Pulse-PDT significantly reduced PDT-induced erythema (P = 0·020), and erythema was even further reduced by S-pulse-PDT (P < 0·001). The complete lesion response rate 3 months after PDT did not differ significantly between the three treated areas.

CONCLUSIONS

Pulse-PDT and S-pulse-PDT reduced erythema 24 h after treatment of multiple mild AKs on the face and scalp. The use of a short MAL application time and topical corticosteroid did not affect the efficacy of PDT and may be an easy way to make PDT treatment of large visible areas more acceptable.

Daylight methyl-aminolevulinate photodynamic therapy versus ingenol mebutate for the treatment of actinic keratoses: an intraindividual comparative analysis

Daylight-photodynamic therapy (D-PDT) and ingenol mebutate (IM) are novel therapies directed to actinic keratoses (AK). The purpose of our study was to compare effectiveness, tolerability, cosmetic outcome and patient preference of D-PDT versus IM in the treatment of grade I and II AK. Twenty-seven patients with AK on the face or scalp were enrolled. Each patient received, in a 25 cm(2) target area, D-PDT on right side and IM on left side. Overall 323 AK were treated. Both target areas achieved complete response in 40.47% of the cases and average AK clearance rate was similar for D-PDT and IM (p=0.74). In D-PDT areas mean grade II AK clearance rate was lower compared with that of grade I AK (p=0.015). In IM areas grade I and II AK average clearance rates were similar (p=0.28). At week 1 and month 1, mean local skin responses (LSR) score were higher in areas treated with IM. IM areas showed more severe pain and cosmetic sequelae. D-PDT had similar effectiveness to IM, even if IM demonstrated higher grade II AK clearance rate. Tolerability profile was superior for D-PDT in terms of LSR and pain. D-PDT was more cosmetically acceptable. Patients preferred D-PDT to IM in most cases.

Spanish-Portuguese consensus statement on use of daylight-mediated photodynamic therapy with methyl aminolevulinate in the treatment of actinic keratosis

INTRODUCTION

Daylight-mediated photodynamic therapy (PDT) is a new type of PDT that is as effective as conventional PDT in grade 1 and 2 actinic keratosis but with fewer adverse effects, resulting in greater efficiency. The climatic conditions in the Iberian Peninsula require an appropriately adapted consensus protocol.

OBJECTIVE

We describe a protocol for the treatment of grade 1 and 2 actinic keratosis with daylight-mediated PDT and methyl aminolevulinate (MAL) adapted to the epidemiological and clinical characteristics of Spanish and Portuguese patients and the climatic conditions of both countries.

METHODS

Twelve dermatologists from different parts of Spain and Portugal with experience in the treatment of actinic keratosis with PDT convened to draft a consensus statement for daylight-mediated PDT with MAL in these countries. Based on a literature review and their own clinical experience, the group developed a recommended protocol.

RESULTS

According to the recommendations adopted, patients with multiple grade 1 and 2 lesions, particularly those at risk of developing cancer, are candidates for this type of therapy. Daylight-mediated PDT can be administered throughout the year, although it is not indicated at temperatures below 10°C or at excessively high temperatures. Likewise, therapy should not be administered when it is raining, snowing, or foggy. The procedure is simple, requiring application of a sunscreen with a protection factor of at least 30 based exclusively on organic filters, appropriate preparation of the lesions, application of MAL without occlusion, and activation in daylight for 2hours.

CONCLUSION

This consensus statement represents a practical and detailed guideline to achieve maximum effectiveness of daylight-mediated PDT with MAL in Spain and Portugal with minimal adverse effects.