Peter Alshede Philipsen

Continuous activation of PpIX by daylight is as effective as and less painful than conventional photodynamic therapy for actinic keratoses; a randomized, controlled, single-blinded study

Background Photodynamic therapy (PDT) is a highly effective treatment for actinic keratoses (AK); however, it is time consuming and often painful for the patient. Daylight‐PDT would make the treatment independent of the clinic and less painful due to the continuous activation of small amounts of porphyrins during its formation.

Detection of skin cancer by classification of Raman spectra

Skin lesion classification based on in vitro Raman spectroscopy is approached using a nonlinear neural network classifier. The classification framework is probabilistic and highly automated. The framework includes a feature extraction for Raman spectra and a fully adaptive and robust feedforward neural network classifier. Moreover, classification rules learned by the neural network may be extracted and evaluated for reproducibility, making it possible to explain the class assignment. The classification performance for the present data set, involving 222 cases and five lesion types, was 80.5%/spl plusmn/5.3% correct classification of malignant melanoma, which is similar to that of trained dermatologists based on visual inspection. The skin cancer basal cell carcinoma has a classification rate of 95.8%/spl plusmn/2.7%, which is excellent. The overall classification rate of skin lesions is 94.8%/spl plusmn/3.0%. Spectral regions, which are important for network classification, are demonstrated to reproduce. Small distinctive bands in the spectrum, corresponding to specific lipids and proteins, are shown to hold the discriminating information which the network uses to diagnose skin lesions.

Pain during photodynamic therapy is associated with protoporphyrin IX fluorescence and fluence rate

Background  Pain during photodynamic therapy (PDT) is a considerable problem that needs to be studied to improve this otherwise attractive treatment of skin diseases.

Ultraviolet exposure patterns of Irish and Danish gardeners during work and leisure

Background  Skin cancer, caused by solar ultraviolet (UV) radiation, is a growing problem in Europe. Reliable data on occupational exposure of outdoor workers are needed to develop protective strategies.

Sunbed Radiation Provokes Cutaneous Vitamin D Synthesis in Humans—A Randomized Controlled Trial

We wanted to investigate whether the use of sunbeds with sunlamps emitting mainly UVA and only 0.5% or 1.4% UVB will increase the level of serum 25‐hydroxyvitamin D (25(OH)D). In a randomized, controlled, open study on healthy, Caucasian females (>50 years) sunbed radiation was given as follows: four 6‐min sunbed sessions (days 0, 2, 4 and 7) and four 12‐min sunbed sessions (days 9, 11, 14 and 16 ) with sunlamps emitting 0.5% UVB (n = 20) or with sunlamps emitting 1.4% UVB (n = 15). The controls (n = 21) had no intervention. Serum levels of 25(OH)D were measured on days 0, 9 and 18 in all three groups. The average increase in serum 25(OH)D from day 0 to day 9 was 12 nmol L−1 (SD 11 nmol L−1, P = 0.0002) in the 0.5% UVB group and 27 nmol L−1 (SD 9 nmol L−1, P < 0.0001) in the 1.4% UVB group. From day 9 to day 18 a further but not significant increase in serum 25(OH)D of 3 nmol L−1 (SD 9 nmol L−1, P = 0.2) in the 0.5% UVB group and 0.6 nmol L−1 (SD 18 nmol L−1, P = 0.9) in the 1.4% UVB group was seen. No significant changes were found in the control group. Increasing with UVB dose and exposure time, 37–64% of the sunbed sessions resulted in side effects such as erythema or polymorphic light eruption. The results showed that sunbeds emitting 0.5% and 1.4% UVB increased 25(OH)D serum levels. The increases were dose dependent but reached a plateau after few sessions. Sunbed use as vitamin D source is, however, not generally recommendable due to the well‐known carcinogenicity and high frequency of acute side effects.

How Finsen's light cured lupus vulgaris

In 1903, Niels Ryberg Finsen was awarded the Nobel Prize for his invention of light therapy for skin tuberculosis (lupus vulgaris). The mechanism of action has not been shown; thus, we wanted to elucidate the mechanism of Finsens light therapy. We measured radiation that could be transmitted through his lens systems and absorption of the stain solution filters in the lamps, and related the obtained results to the possible biological effects on Mycobacterium tuberculosis. Judged from transmission characteristics all tested lens systems were glass lenses (absorbing wavelength <340 nm). The tested filters likewise absorbed wavelengths <340 nm. The methylene blue solution used to absorb heat, blocked out wavelengths below 340 nm and between 550 and 700 nm. Furthermore, fluorescence of M. tuberculosis indicated the presence of porphyrins and HPLC analysis of sonicated M. marinum showed that coproporphyrin III was present, which highly justified that porphyrins were present in M. tuberculosis. Production of singlet oxygen through radiation of porphyrins with light of e.g. 400 nm seems to be a most plausible explanation why Finsens therapy worked in spite of the lack of shortwave ultraviolet radiation, which Finsen believed was the most effective radiation for treating skin tuberculosis.

Morphine Gel 0.3% Does Not Relieve Pain During Topical Photodynamic Therapy: A Randomized, Double-blind, Placebo- controlled Study

There is a demand for pain relief during photodynamic therapy. We therefore investigated the efficacy and side-effects of topical morphine gel 0.3% for pain relief during topical photodynamic therapy in a randomized, double-blind, placebo-controlled study. The study involved 28 patients with actinic keratoses or basal cell carcinomas. Each patient was treated with photodynamic therapy after superficial curettage of 2 treatment areas that were randomized to morphine gel or placebo gel. The gels were applied 15 min before illumination. Pain was assessed pre-illumination, during, and immediately after illumination, using a numeric rating scale. Skin redness was determined by reflectance spectrophotometry and the size of the treated area by protoporphyrin IX fluorescence. There were no differences between the areas according to accumulation of protoporphyrin IX (p =0.34), size of fluorescence areas (p =0.84), or skin redness (p =0.95). There was no significant pain relief of topical morphine gel compared with placebo gel (p >0.23). This negative result suggests that opioid receptors may not be involved in the pain induced by photodynamic therapy.

Combination of ablative fractional laser and daylight‐mediated photodynamic therapy for actinic keratosis in organ transplant recipients – a randomized controlled trial

Topical photodynamic therapy (PDT) for actinic keratoses (AK) is hampered by pain during illumination and inferior efficacy in organ‐transplant recipients (OTR).

Vitamin D Level in Summer and Winter Related to Measured UVR Exposure and Behavior

The influence of the summer UVR exposure on serum‐25‐hydroxyvitamin D (25(OH)D) in late summer and winter was investigated in an open study on 25 healthy, adult volunteers. The UVR exposure dose in standard erythema dose (SED) was monitored continuously during a summer season with personal, electronic wristwatch UVR dosimeters and sun exposure diaries. Constitutive and facultative skin pigmentation was measured in September. 25(OH)D was measured in September and February and was in mean 82 nmol/L ± 25 (mean ± SD) in September and 56 nmol/L ± 19 (mean ± SD) in February. The received cumulative UVR dose measured during a mean of 121 days was 156 SED ± 159 (mean ± SD). The following UVR exposure parameters correlated with 25(OH)D in September and February, respectively: (1) The cumulative UVR dose (r = 0.53; P < 0.01) and (r = 0.43; P = 0.03); (2) Mean daily hours with UVR measurements monitored by the dosimeter (r = 0.64, P = 0.001) and (r = 0.53; P = 0.007); (3) Days “with sun‐exposed upper body” (r = 0.58, P = 0.003) and (r = 0.50; P = 0.01); (4) Facultative pigmentation (r = 0.47; P < 0.02) and (r = 0.7; P < 0.001); (5) Constitutive pigmentation (r = 0.06, n.s.) and (r = 0.43, P = 0.03). Neither days “sunbathing” nor days with “sunscreen applied” correlated with 25(OH)D. The fall in 25(OH)D during winter was dependent on the entry value.

Allergic contact dermatitis to 5-aminolaevulinic acid methylester but not to 5-aminolaevulinic acid after photodynamic therapy

We report a patient with an allergy induced by photodynamic therapy (PDT) following simultaneous treatment with both 5‐aminolaevulinic acid (ALA) and ALA methylester (ALA‐ME). After several PDT treatments the patient presented with acute eczema of the treated areas and itch and hyper‐reactivity of the untreated skin. Patch testing demonstrated a strong +++ reaction to ALA‐ME only, indicating that derivatives common to ALA and ALA‐ME were not involved. This is the first case of allergy to ALA‐ME.