Topical 5-aminolaevulinic Acid Photodynamic Therapy Research Articles

A prospective study of the effect of fire micro-needling plus 5% topical ALA-PDT for the treatment of dissecting cellulitis of the scalp

BackgroundDifferent therapies have been used for dissecting cellulitis of the scalp (DCS) with poor results. Topical 5-aminolaevulinic acid photodynamic therapy (ALA-PDT) is effective for many inflammatory skin diseases. ObjectivesTo evaluate the efficacy and safety of fire micro-needling plus 5% ALA-PDT on DCS. MethodsForty-two male DCS patients were enrolled and treated by four sessions of fire micro-needling plus 5% ALA-PDT (occlusion time: 3 h, 100 mW/cm2 for 20–32 min, 633 ± 10 nm LED) with an interval of 1–2 weeks. The reduction of lesions was evaluated at each follow-up visit. The patients` symptoms were evaluated by Dermatology Life Quality Index (DLQI). All of the side effects were recorded. ResultsForty-one DCS patients finished the treatments and the marked effective rate (MER) reached 65.85%. Ten patients (24.39%) were cured and 17 patients (41.46%) achieved excellent improvement. The median of lesion numbers decreased significantly from 25 to 7 (p < 0.001) with DLQI from 13 to 2 (p < 0.001). Although all the ten cured patients had a relapse during the 12-month follow-up, 5/10 patients had a remission of more than 6 months. All the patients tolerated PDT well with mild adverse effects. ConclusionsFire micro-needling plus 5% ALA-PDT is effective for Chinese male DCS patients without the need to take systemic drugs.

Prostaglandin E2and nitric oxide mediate the acute inflammatory (erythemal) response to topical 5-aminolaevulinic acid photodynamic therapy in human skin

Topical 5-aminolaevulinic acid photodynamic therapy (5-ALA-PDT) causes a clinical inflammatory response in human skin. While histamine mediates the immediate reaction, the mediators of the prolonged erythema are unknown. To look for involvement of the proinflammatory mediators prostaglandin (PG)E2 and nitric oxide (NO) in topical PDT-induced erythema in human skin. A series of studies was performed in healthy volunteers (n = 35). Following definition of the erythemal time course and dose response to 5-ALA-PDT, duplicate 5-ALA dose series were iontophoresed into the skin of each ventral forearm and exposed to 100 J cm(-2) broadband red light. Within subject, arms were randomized to control, or treatment with the cyclooxygenase and NO synthase inhibitors indometacin and Nω -nitro-l-arginine methyl ester (l-NAME), respectively, and the impact on 5-ALA-PDT-induced erythema was quantified. Additionally, release of PGE2 and NO was directly assessed by sampling dermal microdialysate at intervals following 5-ALA-PDT administration. A 5-ALA dose-related delayed erythema occurred by 3 h (r = 0·97, P < 0·01), with erythema persisting to 48 h post-PDT. Topical indometacin applied immediately post-PDT reduced the slope of erythemal response at 3 h and 24 h (P < 0·05). Intradermal injection of l-NAME into 5-ALA-PDT-treated sites reduced the slope of response at 24 h post-PDT (P < 0·001), while significantly inhibiting erythema from 3 h to 48 h post-PDT (P < 0·01). Analysis of dermal microdialysate showed release of NO and PGE2 following treatment. Topical 5-ALA-PDT upregulates PGE2 and NO in human skin, where they play a significant role in the clinical inflammatory response. The potential relevance of these mediators to PDT in human cutaneous pathology warrants study.

5‐aminolevulinic acid‐based photodynamic therapy for the treatment of condylomata acuminata in Chinese patients: a meta‐analysis

This meta-analysis was designed to assess the efficacy of topical 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) in Chinese patients with condylomata acuminata (CA). Electronic literature databases (Medline, Embase, Cochrane Library, China National Knowledge Infrastructure, and Wanfang database) were searched for relevant randomized controlled trials (RCTs) published prior to October 2012. Only RCTs that compared ALA-PDT to non-ALA-PDT for patients with genital condylomata were selected. The outcomes included the recurrence rate and adverse events. The risk ratios (RRs) and 95% confidence intervals (CIs) were calculated as the ALA-PDT vs. without ALA-PDT. Twenty RCTs composed of 1903 patients (ALA-PDT, n = 1106; non-ALA-PDT, n = 797) were included in the meta-analysis. ALA-PDT decreased the recurrence rate within 12 week after treatment (vs. without ALA-PDT, RR: 0.28, 95% CI: 0.22-0.35) and 24 week after treatment (vs. without ALA-PDT, RR: 0.24, 95% CI: 0.17-0.34) in a fixed-effect model. The common adverse events related ALA-PDT included a mild burning and/or stinging sensation, erythema, mild edema, erosion, and hyperpigmentation. Local application of ALA-PDT reduced recurrence rate vs. without ALA-PDT. The use of ALA-PDT should be considered as a feasible therapy for the treatment of CA.

High and sustained efficacy after two sessions of topical 5-aminolaevulinic acid photodynamic therapy for basal cell carcinoma: a prospective, clinical and histological 10-year follow-up study

Prolonged follow-up data on topical photodynamic therapy (PDT) in basal cell carcinoma (BCC) are necessary for a full evaluation of its effect and for comparison with conventional treatment methods. To assess 10-year long-term PDT efficacy in primary and recurrent BCC and to evaluate clinical and histopathological factors which may be associated with treatment failure. We performed a longitudinal study on 60 histologically verified BCCs in 44 patients treated with curettage and one or two sessions of dimethylsulphoxide (DMSO)-supported topical 5-aminolaevulinic acid (ALA)-based PDT. Treated lesions were investigated by clinical and histopathological examination at regular intervals. The main outcomes were 10-year lesion complete response rate using a time-to-event analysis, histological treatment failure and cosmesis. Overall complete response rate for all lesions was 75% (95% confidence interval 64-87%); 60% after one and 87% after two treatment sessions. The response rate was 78% for primary lesions; 63% after one and 90% after two sessions. The cosmetic outcome was rated as good or excellent in 91-100% of evaluated cases. Treatment failure was documented in 15 (25%) of 60 lesions; clinical investigation identified 14 of them. All failures were noted within 3 years of treatment. Male gender, recurrent tumour and one treatment session were factors significantly associated with treatment failure. The only lesion larger than 2·0 cm relapsed. Two sessions of DMSO-supported topical ALA-PDT and curettage can provide long-term effective treatment results with favourable cosmetic outcome in primary, small BCC.

Investigation of optimal aminolaevulinic acid concentration applied in topical aminolaevulinic acid–photodynamic therapy for treatment of moderate to severe acne: a pilot study in Chinese subjects

Investigation of optimal aminolaevulinic acid concentration applied in topical aminolaevulinic acid–photodynamic therapy for treatment of moderate to severe acne: a pilot study in Chinese subjects

Topical aminolaevulinic acid-photodynamic therapy produces an inflammatory infiltrate but reduces Langerhans cells in healthy human skin in vivo

Topical photodynamic therapy (PDT) elicits a therapeutic response in both skin cancer and immune-mediated skin disorders. While PDT induces direct cell death, host inflammatory and immune responses to PDT may contribute to the therapeutic effects. To examine the impact of topical PDT on leucocyte trafficking and mediators of chemotaxis in healthy human skin. Aminolaevulinic acid (ALA)-PDT was performed on the buttock skin of seven healthy volunteers. Biopsies for immunohistochemical assessment were taken 1, 4 and 24 h post-PDT and from untreated contralateral buttock skin (baseline). A significant dermal neutrophilic infiltrate appeared early, peaking at 4 h (P < 0·01) and returning to near baseline by 24 h. Expression of E-selectin was significantly higher at 4 h (P < 0·05) and correlated strongly with neutrophil numbers (r = 0·93). Expression of intercellular adhesion molecule 1 was significantly elevated after 24 h (P < 0·05) with an apparent gradual increase in CD4+ T cells up to this time point. Notably, epidermal Langerhans cells were significantly reduced 24 h post-PDT compared with baseline (P < 0·01) and comprised a significantly larger proportion of cells with migratory rather than dendritic morphology (P < 0·05). The number of epidermal cells expressing tumour necrosis factor-α significantly increased at 4 h (P < 0·05) and remained elevated 24 h post-PDT, whereas no significant change in expression of interleukin (IL)-1β or IL-8 was seen. Reduction of Langerhans cells by topical PDT of human skin may play a significant role in PDT-induced local immunosuppression, potentially benefiting the treatment of immune-mediated skin disorders but negatively impacting on antitumour responses. Further exploration according to disease indication/treatment protocol is warranted.

Photodynamic therapy of non-melanoma skin cancers

In this prospective study duly approved from Institutional Ethics Review Committee for research in medicine, PAEC General Hospital Islamabad, Pakistan, we investigate the efficacy, safety and tolerability along with cosmetic outcome of topical 5-aminolaevulinic acid photodynamic therapy for superficial nonmelanoma skin cancers (NMSCs) and their precursors. Patients with Histological diagnosis of NMSCs and their precursors were assessed for PDT, after photographic documentation of the lesions and written consent, underwent two (2) sessions of PDT in one month (4 weeks) according to standard protocol. A freshly prepared 20% 5-ALA in Unguentum base was applied under occlusive dressing for 4–6 h as Drug Light Interval (DLI) and irradiated with light of 630 nm wavelength from a diode laser at standard dose of 90 J/cm2. Approximately 11% patients reported pain during treatment which was managed in different simple ways. In our study we regularly followed up the patients for gross as well as histopathological response and recurrence free periods during median follow-up of 24 months. Regarding Basal cell carcinomas complete response was observed in 86.2% (25/29), partial response in 10.3% (3/29) and recurrence during first year in 3.5% (1/29) lesions. All the lesions which showed partial response or recurrence were nBCCs. Regarding Actinic Keratosis complete response was observed in 95.3% (20/21), partial response in 4.7% (1/21) while Bowen’s disease showed 100% (2/2) results. 81.8% (9/11) Squamous Cell Carcinomas showed complete, 9% (1/11) partial response and 9% (1/11) presented with recurrence after 3 months. We observed excellent and good cosmetic results along with tumor clearance in our study. Treatment sessions were well tolerated with high level of patient’s satisfaction and only minor side effects of pain during treatment sessions and inflammatory changes post photodynamic therapy were observed. We concluded that 5-ALA PDT is an effective and safe emerging treatment modality for management of superficial non-melanoma skin cancers and their precursors with better cosmetic outcome and minor side effects.

Cosmetic efficacy of topical 5-aminolaevulinic acid-photodynamic therapy on cephalic and facial skin tumors

Objective To investigate and summarize the clinieal effects and cosmetic results of 5-aminolaevulinic acid-photodynamic therapy (ALA-PDT) on cephalic and facial skin tumors.Methods Patientswith skin basal eell carcinoma(BCC),squamous cell carcinoma (SCC),keratosis seborrheica (KS),and solar keratosis (SK) were included in this study.Inoperable cases were given topical ALAPDT,and received clinical response evaluation and satisfying questionnaire after 3 months follow-up.Resalts28 patients including 16 BCCs,8 SCCs,2 KSs and 2 SKs received ALA-PDT.100% BCC had responseto PDT,including 15 cases with complete response (CR);only one recurred.Overall response rate was 67% for SCC,2 of 8 cases failed to continue the treatment,3 eases CR,1 case partial response (PR) and 1 patient with no response.Response rate was 0% in KS.100% of SK had response to PDT,and 2 cases showed CR and PR,respectively.64.2% patients (18/28) showed extreme satisfaction for cosmetic outcome,11% (3 cases) satisfaction,7.1% (2 cases) little satisfaction,and 10.7% (3 cases) no satisfaction.Conclusion Topical ALA-PDT is an effective and satisfied treatment with lower recurrent rates, especially for cephalic and facial skin tumors including BCC,SCC and SK,but no response for KS. Key words: Photodynamic therapy; 5-Aminolaevulinic acid; Skin tumor; Face

Investigation of optimal aminolaevulinic acid concentration applied in topical aminolaevulinic acid-photodynamic therapy for treatment of moderate to severe acne: a pilot study in Chinese subjects

Aminolaevulinic acid-photodynamic therapy (ALA-PDT) is a novel and effective treatment in acne. However, little is known about the effect of different concentrations of ALA in the treatment of acne in Chinese patients with Fitzpatrick skin type III and IV. To investigate the efficacy and safety of ALA-PDT in the treatment of moderate to severe acne in Chinese patients and to identify the suitable concentration of topical ALA. One hundred and eighty patients with moderate to severe facial acne were recruited and randomly divided into four groups. Each group was treated with a different concentration (5%, 10%, 15% and 20%) of ALA to the facial lesions on the right side and placebo agent on the left side as control. Each patient was treated once every 10 days for four sessions. The numbers of inflammatory and noninflammatory acne lesions were counted at baseline and at weeks 2, 4, 12 and 24 after the last treatment. Adverse effects were recorded at each follow-up visit. After 24 weeks, each side treated by ALA-PDT showed clinical improvement compared with the control side treated by red light alone (P < 0·01). Statistically significantly more patients treated with 20% ALA than with 15% or 10% ALA achieved complete clearance. Regarding side-effects, a trend towards more serious erythema and pigmentation was observed with increasing ALA concentration. Increasing the concentration of ALA seems to be beneficial for improving the results. Considering effectiveness and safety, ALA-PDT using 10% or 15% ALA is suggested to the ideal treatment for moderate to severe acne in Chinese patients with Fitzpatrick skin type III and IV.

Long-term follow-up of topical 5-aminolaevulinic acid photodynamic therapy diode laser single session for non-melanoma skin cancer

Photodynamic therapy (PDT) is based on the association of a light source and light sensitive agents in order to cause the selective death of tumor cells. To evaluate topical 5-aminolaevulinic acid (5-ALA) and diode laser photodynamic single session therapy single session for non-melanoma skin cancer (NMSC), a long-term follow-up was performed. Nineteen Bowen's disease (BD) and 15 basal cell carcinoma (BCC) lesions were submitted to 6-h topical and occlusive 20% 5-ALA plus DMSO and EDTA, and later were exposed to 630 nm diode laser, 100 or 300 J cm(-2) dose. At 3 months tumor-free rate was 91.2% (31/34) whereas at 60 months, 57.7% (15/26), slightly higher in BCC (63.6%; 7/11). The relation between the reduction of the clinical response and the increase of tumor dimension observed at 18 months was lost at 60 months. The sBCC recurrence was earlier compared to the nBCC one. ALA-PDT offered important advantages: it is minimally invasive, an option for patients under risk of surgical complications; clinical feasibility; treatment of multiple lesions in only one session or lesions in poor healing sites and superior esthetical results. However, the recurrence rate increase after ALA-PDT diode laser single session can be observed at long-term follow-up, and the repetitive sessions, an additional advantage of the method, is strongly recommended. The clinical response and recurrence time seem to be related to the laser light dose and NMSC types/sub-types, thickness and dimension, which must be considered for the choice of the ALA-PDT.

Randomized, double-blind, prospective study to compare topical 5-aminolaevulinic acid methylester with topical 5-aminolaevulinic acid photodynamic therapy for extensive scalp actinic keratosis

Randomized, double-blind, prospective study to compare topical 5-aminolaevulinic acid methylester with topical 5-aminolaevulinic acid photodynamic therapy for extensive scalp actinic keratosis

Randomized, double-blind, prospective study to compare topical 5-aminolaevulinic acid methylester with topical 5-aminolaevulinic acid photodynamic therapy for extensive scalp actinic keratosis

5-aminolaevlinic acid methylester (MAL) and 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) are both effective treatment options for actinic keratosis (AK). While MAL is significantly more expensive than ALA, no studies have directly compared their efficacy in the treatment of extensive scalp AK. To compare the efficacy and adverse effects of MAL-PDT with ALA-PDT in the treatment of scalp AK. Sixteen male patients aged 59-87 years with extensive scalp AK were randomized into a double-blind, split-scalp prospective study. Two treatment fields were defined (right and left frontoparietal scalp) and treated 2 weeks apart. These fields were randomized to receive either MAL or ALA as first or second treatment. MAL cream was applied for 3 h; 20% ALA cream was applied for 5 h. A blinded observer assessed efficacy comparing AK counts before and 1 month after treatment. Pain was assessed using a visual analogue scale at 3, 6, 12 and 16 min. Fifteen patients completed treatment to both fields. There was a mean reduction from baseline in AK counts with the use of ALA-PDT of 6.2 +/- 1.9 compared with 5.6 +/- 3.2 with MAL-PDT (P = 0.588). All patients experienced pain which was of greater intensity in the ALA-treated side at all time points: 3 min (P = 0.151), 6 min (P = 0.085), 12 min (P = 0.012) and 16 min (P = 0.029). Similarly, duration of discomfort post-procedure persisted for longer following treatment with ALA when compared with MAL-PDT (P = 0.044). This study demonstrates that both ALA-PDT and MAL-PDT result in a significant reduction in scalp AK. There is no significant difference in efficacy. However, ALA-PDT is more painful than MAL-PDT in the treatment of extensive scalp AK.

Acute phototoxicity with urticarial features during topical 5-aminolaevulinic acid photodynamic therapy

Conflict of interest: there are no conflicts of interest. A 47‐year‐old man presented for photodynamic therapy (PDT) of a histologically confirmed superficial basal cell carcinoma (sBCC) on the shoulder. He had Fitzpatrick skin type I, red hair and a history of working in the tropics. He had no significant medical history and was not on phototoxic medication. At presentation, he had several areas of actinic damage and multiple sBCCs on his back and shoulders. A shoulder lesion (diameter 25 mm) was treated twice (8‐week interval) after gentle surface curettage, with topical 5‐aminolaevulinic acid (ALA)‐PDT for 6 h under occlusion (20% ALA; Chapter, Huntingdon, UK). Fluorescence under Wood's light illumination after ALA application was strong (i.e. grade 3 on a visual scale of 0–3) and specific to the lesion. Irradiation was performed using a light source fitted with light‐emitting diodes (irradiation field 30 mm, 76 mW/cm2, 75 J/cm2; Aktilite LED 16; Photocure, Oslo, Norway). PDT was associated with mild to moderate pain, erythema, and urticaria at the treatment site.

Invasive squamous cell carcinoma arising in refractory perianal Bowen's disease in a HIV‐positive individual

A 54-year-old HIV-positive homosexual man presented with erythematous and pigmented plaques on background erythema in the perianal region, histologically consistent with Bowen's disease. Perianal Bowen's disease represents high-grade anal intraepithelial neoplasia, which is considered a precursor lesion of invasive anal squamous cell carcinoma. This patient's anal intraepithelial neoplasia was unresponsive to multiple treatment modalities including cryotherapy, serial curettage and cautery, topical 5-fluorouracil and 5-aminolaevulinic acid photodynamic therapy. He progressed to develop a poorly differentiated squamous cell carcinoma of the anus three and a half years after the Bowen's disease was diagnosed. The squamous cell carcinoma was treated with combined chemoradiation. A recurrence of high-grade anal intraepithelial neoplasia was noted 6 months after completion of chemoradiation.

Photodynamic Therapy for Urological Malignancies: Past to Current Approaches

Modern PDT for urological tumors is a potentially selective approach in which in situ photosensitization by a nontoxic drug, locally activated by light, generates cytotoxic reactive oxygen species, causing cell death. While urological clinical experience with PDT is largely limited to treatment for superficial bladder cancer, the advent of novel photosensitizers and technologies for treatment planning, light delivery and dosimetry, PDT for prostate and other urological cancers appears increasingly realistic. We reviewed the current literature on PDT for urological tumors, in addition to recent emerging data from our laboratory and elsewhere. Remarkable progress has been made in the field of photochemistry and photobiology. Together with improved optical delivery and imaging systems PDT holds promise as an alternative, minimally invasive and potentially curative treatment for localized solid tumors as well as for palliative treatment for isolated, clinically problematic metastases. Current experience with photodynamic therapy using contemporary photosensitizing agents and light sources is mainly restricted to in vivo experimental models and early phase clinical trails. However, ongoing preclinical work and clinical trials indicate that safer and effective PDT treatments in uro-oncology are imminent.

Randomized, double-blind, placebo-controlled prospective study of the efficacy of topical anaesthesia with a eutetic mixture of lignocaine 2·5% and prilocaine 2·5% for topical 5-aminolaevulinic acid-photodynamic therapy for extensive scalp actinic keratos

Photodynamic therapy (PDT) is an effective treatment modality for the treatment of extensive scalp actinic keratoses (AKs), but pain is a significant drawback when treating large areas with topical PDT using 5-aminolaevulinic acid (ALA) as sensitizer. A recent study has shown that use of tetracaine gel (Ametop) did not significantly reduce pain associated with PDT. To assess the benefit of a eutetic mixture of lignocaine 2.5% and prilocaine 2.5% (Emla) on pain during topical ALA-PDT treatment of scalp AKs. Fourteen men aged 59-83 years with extensive scalp AKs were recruited into a double-blind placebo-controlled study. Two treatment fields were defined (right and left frontal scalp) and were treated 2 weeks apart. These fields were randomized to receive either Emla or Aqueous cream as first or second treatment. ALA 20% cream was applied for 4 h. Topical anaesthesia or Aqueous cream was applied for 2 h. Pain was assessed using a visual analogue scale (0-100 mm) at 3, 6, 12 and 16 min. The instrument used for this was a blinded counter with one side reading 'no pain' to 'worst pain ever' with a numerical scale (0-100) on the reverse side. Pain scores were assessed looking at median and interquartile range and confidence intervals and calculating differences between treatment groups and analysing them using a paired t-test. Thirteen patients received treatment to both fields. No significant difference in mean pain scores was seen with the use of Emla cream compared with placebo during treatment of scalp AKs (P = 0.328). There was no significant difference in requirement for oral analgesia following PDT between the two groups (P = 0.06). Our data do not support the routine use of topical anaesthesia with Emla for topical PDT.

Recalcitrant palmoplantar pustular psoriasis successfully treated with topical 5-aminolaevulinic acid photodynamic therapy

Recalcitrant palmoplantar pustular psoriasis successfully treated with topical 5-aminolaevulinic acid photodynamic therapy

Topical 5-aminolaevulinic acid-photodynamic therapy for the treatment of urethral condylomata acuminata

Electrocoagulation and laser evaporation for urethral condylomata acuminata have high recurrence rates and can be associated with urethral malformations. To investigate the effect of photodynamic therapy (PDT) with topical 5-aminolaevulinic acid (ALA) on urethral condylomata acuminata and to examine the histological changes in lesions of condylomata acuminata after ALA-PDT. Patients with urethral condylomata (n = 164) were given topical ALA followed by intraurethral PDT through a cylindrical fibre. Patients included 11 individuals with 16 penile or vulval condylomatous lesions which were biopsied before or after treatment; the histological changes were then evaluated by light microscopy and electron microscopy. The complete response rate was 95% and the recurrence rate was 5% after 6-24 months of follow-up. Light microscopy revealed keratinocytes in the middle and upper layers of the epidermis showing marked vacuolation and some necrocytosis 1 and 3 h after PDT. Necrosis in all layers of the epidermis was noted 5 h after PDT. Electron microscopy of keratinocytes revealed distinct ultrastructural abnormalities of mitochondria and the endoplasmic reticulum, and membrane damage. Apoptotic bodies were detected 3 h after PDT and a large number of keratinocytes exhibited necrosis 5 h after PDT. Results suggest that, compared with conventional therapies, topical ALA-PDT is a simple, effective, safe and well-tolerated treatment for urethral condylomata acuminata that is associated with a low recurrence rate. The mechanism might be the triggering of both apoptosis and necrosis by ALA-PDT in human papillomavirus-infected keratinocytes.

The characteristics of erythema induced by topical 5-aminolaevulinic acid photodynamic therapy.

Topical photodynamic therapy (PDT) is increasingly used to treat superficial non-melanoma skin cancers. Knowledge of the characteristics of 5-aminolaevulinic acid (ALA)-induced phototoxicity will increase our understanding of PDT and may facilitate optimisation of treatment regimes. We examined the characteristics of ALA-induced erythema in 10 healthy subjects and investigated the effect of light source and body site. Maximal erythema occurred within 1-2 h of PDT and inter-individual variation in ALA-induced phototoxicity was seen. No detectable differences were seen in the phototoxicity on back or leg sites or between coherent and non-coherent light sources. These data provide further information to allow us to optimise topical PDT regimes.

Topical 5-aminolaevulinic acid photodynamic therapy for the treatment of skin conditions other than non-melanoma skin cancer.

Topical 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) is used increasingly for superficial non-melanoma skin cancer (NMSC) and dysplasia. However, the relative accumulation of the photosensitizer protoporphyrin IX (PpIX) in diseased tissue is not specific for neoplastic disease, and has been shown after the application of ALA to benign proliferative skin conditions such as viral warts and psoriasis. This review appraises the quality of evidence available for the use of topical ALA-PDT in the treatment of skin conditions other than NMSC. The diseases that have been studied in most detail are recalcitrant viral warts, acne, psoriasis and cutaneous T-cell lymphoma. Publications relating to the treatment of other diseases by topical PDT are restricted to small case series or case reports. The relevant literature will be discussed and the potential for topical PDT in the treatment of several skin diseases is highlighted, although more detailed studies are required to clarify the role of PDT beyond the treatment of NMSC.