Editorial: The Value of New Knowledge.

is missing (Editorial).

The risk of skin cancer in psoriasis patients treated with UVB therapy.

Phototherapy is an effective and widely used treatment for generalised plaque psoriasis. Despite the mutagenic effects of UVB this type of therapy is still assumed to be a safe treatment option. We have performed a cross sectional study to assess the risk of skin cancer in the cohort of psoriasis patients treated with UVB. A total of 162 white patients (116 men and 46 women, mean ± standard deviation age 56.0 ± 13.5 years) were included in the study. All patients have previously been treated with UVB at least 100 times in the last 5 years. Eight patients (4.9%, 0.95 CI: 2.2-9.5%) out of the 162 included in the study had histopathologically verified skin cancer. We found that the risk of skin cancer in psoriasis patients treated with UVB correlated with the number of treatments (controlling for age) but not with the type of UVB lamp. How-ever, the overall risk of malignancy in the UVB-treated patients was not greater than in the general population.

Fluorescence diagnostics of basal cell carcinomas comparing methyl-aminolaevulinate and aminolaevulinic acid and correlation with visual clinical tumour size.

Fluorescence diagnostics based on aminolaevulinic acid (ALA) fluorescence has been suggested as an in vivo pre-surgical tool for tumour demarcation. We performed fluorescence diagnostics of 35 basal cell carcinomas (BCCs) undergoing photodynamic therapy (PDT) using methyl-aminolaevulinate (MAL). In addition, a semi-automated thresholding algorithm was implemented to detect the potential tumour region. The mean tumour fluorescence contrast was found to be 1.65 ± 0.06 during the first MAL-PDT session, and increased to 1.84 ± 0.07 at the second treatment (p < 0.01). This could imply that disruption of the skin barrier and inflammatory responses after the first session of PDT led to higher accumulation of proto-porphyrin IX during the second session of PDT. The tumour areas detected based on fluorescence in small BCCs (< 1 cm(2)) were in general (n = 18/23) larger than the visual clinical tumour size. In addition, the fluorescence contrast using MAL (1.65 ± 0.06) was found to be significantly higher (p<10(-4)) than the contrast (data from previous study) after application of ALA (1.20 ± 0.06). Thus, MAL generally provides higher tumour contrast than ALA in BCCs, and should be preferred for use in fluorescence diagnostics. Correlation between fluorescence, lack of treatment response and/or pain was not observed.

Vitamin D production in psoriasis patients increases less with narrowband than with broadband ultraviolet B phototherapy.

BACKGROUND: Phototherapy of psoriasis is an effective treatment. In addition to standard broadband ultraviolet radiation B (UVB), (280-320 nm), narrowband phototherapy (NBUVB) (monochromatic UV between 311 and 312 nm) has become an important treatment for psoriasis. The same wavelength range of UVB (290-315 nm) induces synthesis of vitamin D. The aim was to compare the effect of broadband with NBUVB therapy on vitamin D synthesis in patients with psoriasis. METHODS: Sixty-eight Caucasian patients (17 women and 51 men) mean age 54.1 +/- 16.0 years, with active plaque psoriasis, were treated with broadband UVB (n=26) or NBUVB (n=42) two to three times/week for 8-12 weeks. The serum concentrations of 25-hydroxyvitamin D (25(OH)D3), 1,25-dihydroxyvitamin D (1,25(OH)(2)D3), intact parathyroid hormone (PTH), calcium and creatinine were measured before the first exposure and after the last dose of radiation. RESULTS: In broadband UVB treated patients, 25(OH)D3 increased from 37.9 +/- 16.9 to 69.4 +/- 19.7 ng/ml (P<0.0001) and in patients treated with NBUVB from 34.8 +/- 11.9 to 55.3 +/- 17.6 ng/ml (P<0.0001) and P=0.008 between the treatment groups. PTH decreased on broadband UVB (P<0.05). The serum concentrations of 1,25(OH)(2)D3, calcium or creatinine remained unaltered. CONCLUSION: Serum 25(OH)D3 in psoriasis patients increased less with NBUVB than with broadband UVB phototherapy. Psoriasis improved on both regimens.

Photostability of commercial sunscreens upon sun exposure and irradiation by ultraviolet lamps.

BACKGROUND: Sunscreens are being widely used to reduce exposure to harmful ultraviolet (UV) radiation. The fact that some sunscreens are photounstable has been known for many years. Since the UV-absorbing ingredients of sunscreens may be photounstable, especially in the long wavelength region, it is of great interest to determine their degradation during exposure to UV radiation. Our aim was to investigate the photostability of seven commercial sunscreen products after natural UV exposure (UVnat) and artificial UV exposure (UVart). METHODS: Seven commercial sunscreens were studied with absorption spectroscopy. Sunscreen product, 0.5 mg/cm2, was placed between plates of silica. The area under the curve (AUC) in the spectrum was calculated for UVA (320-400 nm), UVA1 (340-400 nm), UVA2 (320-340 nm) and UVB (290-320 nm) before (AUCbefore) and after (AUCafter) UVart (980 kJ/m2 UVA and 12 kJ/m2 of UVB) and before and after UVnat. If theAUC Index (AUCI), defined as AUCI = AUCafter/AUCbefore, was > 0.80, the sunscreen was considered photostable. RESULTS: Three sunscreens were unstable after 90 min of UVnat; in the UVA range the AUCI was between 0.41 and 0.76. In the UVB range one of these sunscreens was unstable with an AUCI of 0.75 after 90 min. Three sunscreens were photostable after 120 min of UVnat; in the UVA range the AUCI was between 0.85 and 0.99 and in the UVB range between 0.92 and 1.0. One sunscreen showed in the UVA range an AUCI of 0.87 after UVnat but an AUCI of 0.72 after UVart. Five of the sunscreens were stable in the UVB region. CONCLUSION: The present study shows that several sunscreens are photounstable in the UVA range after UVnat and UVart. There is a need for a standardized method to measure photostability, and the photostability should be marked on the sunscreen product.

Bispectral fluorescence imaging combined with texture analysis and linear discrimination for correlation with histopathologic extent of basal cell carcinoma.

Fluorescence imaging has been shown to be a potential complement to visual inspection for demarcation of basal cell carcinoma (BCC), which is the most common type of skin cancer. Earlier studies have shown promising results when combining autofluorescence with protoporphyrin IX (Pp IX) fluorescence, induced by application of delta-5-aminolaevulinic acid (ALA). In this work, we have tried to further improve the ability of this technique to discriminate between areas of tumor and normal skin by implementing texture analysis and Fisher linear discrimination (FLD) on bispectral fluorescence data of BCCs located on the face. Classification maps of the lesions have been obtained from histopathologic mapping of the excised tumors. The contrast feature obtained from co-occurrence matrices was found to provide useful information, particularly for the ALA-induced Pp IX fluorescence data. Moreover, the neighborhood average features of both autofluorescence and Pp IX fluorescence were preferentially included in the analysis. The algorithm was trained by using a training set of images with good agreement with histopathology, which improved the discriminability of the validation set. In addition, cross validation of the training set showed good discriminability. Our results imply that FLD and texture analysis are preferential for correlation between bispectral fluorescence images and the histopathologic extension of the tumors.

[Increasing number of skin cancer cases--also among the younger]. / Antalet hudcancerfall ökar--även bland yngre. Allt fler behandlingsalternativ ger möjlighet till mindre destruktiva ingrepp.

The incidence of skin cancer has been increasing for several years. This is the case in malignant melanoma as well as in squamous cell carcinoma and basal cell carcinoma. Skin cancer is most common among the elderly, but is now also more frequently found in younger people. Surgery is often the treatment of choice and this is still the case in malignant melanoma and most cases of squamous cell carcinoma. For basal cell carcinoma, Bowen's disease and actinic keratoses, however, alternative treatments should be considered. Today, dermatologists can offer patients with skin cancer several new treatments besides surgery. These new treatments seem to have the same efficacy but better cosmetic results compared to earlier treatments.

Vitamin D production after UVB exposure - a comparison of exposed skin regions.

BACKGROUND: Cholecalciferol is an essential steroid produced in the skin by solar ultraviolet B radiation (UVB 290-315nm). Skin production of cholecalciferol depends on factors affecting UVB flux, age and exposed skin area. PURPOSE: Serum cholecalciferol and 25-hydroxyvitamin D3 [25(OH)D3] concentrations were measured after UVB irradiation of 3 different skin areas to compare the skin capacity to produce vitamin D in different anatomic sites in the same individuals. METHOD: Ten voluntary Caucasians (skin photo type II & III, aged 48±12years (±SD)) were exposed to broadband UVB (280-320nm) between February and April. Hands and face, upper body and whole body were exposed to a suberythemic dose of UVB (median 101mJ/cm(2) (min 66, max 143)) (for 3 subsequent days 24h apart with a wash out period of about 3weeks (median 18days (min 11, max 25)) between the exposures of respective area. Serum concentrations of cholecalciferol and 25(OH)D3, were measured immediately before the first and 24h after the last dose of radiation. RESULTS: There was a significantly higher increase in serum cholecalciferol after UVB exposure of the two larger skin areas compared to face and hands, but no difference in increase was found between upper body and whole body exposures. CONCLUSION: Exposure of a larger skin area was superior to small areas and gave greater increase in both serum cholecalciferol and serum 25(OH)D3 concentrations. However, exposure of face and hands, i.e. only 5% of the body surface area, was capable of increasing serum concentrations of 25(OH)D3.

Size of the exposed body surface area, skin erythema and body mass index predict skin production of vitamin D.

BACKGROUND: Cholecalciferol (vitamin D3), produced in the skin by UVB irradiation (290-315nm) of 7-dehydrocholesterol, is metabolized in the liver into 25-hydroxyvitamin D [25(OH)D] which is a major circulating metabolite. AIM: To examine changes in serum concentrations of cholecalciferol and its metabolites after UVB exposure of different skin areas. METHODS: 21 healthy Caucasians (skin type II and III, aged 23-47years) were exposed to broadband UVB (290-320nm) and randomized to either exposure to one minimal erythema dose given as a single dose, or a suberythemic dose given for 3 subsequent days. The following areas were exposed: face and back of hands, upper half of the body and the whole body, respectively. Serum cholecalciferol and 25(OH)D were measured immediately before start and 24h after the 1st and last exposure, respectively. RESULTS: Subjects with whole body exposure had an average S-cholecalciferol increase per dose unit of 0.18ngml(-1)mJ(-1)cm(2), 0.95 CI: (0.16, 0.20), upper body treatment 0.13ngml(-1)mJ(-1)cm(2), 0.95 CI: (0.10, 0.15) and face and hands exposure 0.013ngml(-1)mJ(-1)cm(2), 0.95 CI: (-0.012, 0.037). The increase in cholecalciferol correlated positively to the UVB dose and skin erythema and negatively to body mass index (BMI) when controlling for other factors. Exposure of face and hands induces smaller cholecalciferol production in comparison with exposure of larger skin areas. CONCLUSION: Size of the exposed skin area, UVB dose, skin erythema and BMI were the major determinants for serum levels of skin synthesized cholecalciferol. Exposure of hands and face induces smaller cholecalciferol production in comparison with exposure of larger skin areas.

Fluorescence contrast and threshold limit: implications for photodynamic diagnosis of basal cell carcinoma.

This study was designed to evaluate what application time of delta-5-aminolaevulinic acid (ALA) results in highest contrast between tumour and normal skin, in the interval 1-4 h, when using photodynamic diagnosis (PDD) of basal cell carcinomas (BCC) located on the face. Moreover, a value of the demarcation limit has been derived based on the fluorescence variation in normal skin adjacent to the tumour. Forty patients were included in the study, randomly allocated to four different groups with varying ALA application time in the range 1-4 h. The contrast, defined as the ratio between the fluorescence intensity in ALA-treated tumour tissue and normal skin, was calculated for each patient, and the mean values in each group were evaluated as a function of ALA application time. In addition, the fluorescence intensity variation in ALA-treated normal skin adjacent to the tumour was assessed. The results from this study show a peak of the mean contrast values after 3 h ALA application, but due to large interpatient variation, the mean contrast did not differ significantly in the interval 2-4 h. After 2 h ALA application, the fluorescence intensity variation in the normal ALA-treated skin was found to be at a maximum, which suggests that 2 h ALA application is not preferable when using PDD. Based on data of the fluorescence variation in ALA-treated normal skin after 3 and 4 h ALA application, a tolerance interval was calculated implying that values above 1.4 times the mean normal fluorescence indicate an abnormal condition. This tolerance limit agrees well with results obtained in a former study.

[Normal doses of visible light can cause mutations in skin]. / Normala doser synligt ljus kan ge mutationer i huden.

Therapeutic and undesired effects of long-wave (UVA1) (340-400 nm) and visible light were studied. Mutagenicity were investigated after repeated doses encountered in normal situations in the sun. Laser treatment of naevus flammeus was studied with a new 600 nm laser. Also, the effect of photodynamic therapy on cutaneous lymphomas was reported. Both UVA1 and visible light can induce mutations in normal skin after repeated doses. The findings indicate that clothing, not sunscreens, should form the basis of sun protection. In selected cases, the new 600 nm laser may be advantageous in the treatment of naevus flammeus. Localized cutaneous lymphoma may be effectively treated with photodynamic therapy.

Cryosurgery of eyelid basal cell carcinomas including 781 cases treated over 30 years.

PURPOSE: To present the results of a 30-year prospective study in which eyelid basal cell carcinomas were treated with cryosurgery. METHODS: Basal cell carcinomas with well-defined borders on the eyelids or medial canthus, diagnosed by punch biopsy, were included. Cryosurgery was performed using liquid nitrogen sprayed into a cone circumscribing the tumours. The tumours were treated in a double freeze-thaw cycles technique. The minimum thawing time of the frozen area outside the tumour margin was at least 60 seconds. During the first 20 years of the study, patients were re-examined for up to 10 years. In the last 10 years of the study, most patients were followed up for 1 year, and if there was no visible scarring in the treated area at the 1-year check-up, follow-ups were implemented at the patient's request following self-assessment. RESULTS: In total, 781 tumours in 768 patients were treated. The median age of the patients at treatment was 73 years, mean 70.9 years (range 22-102 years). More women (58%) were treated than men. The median tumour size was 8 mm, mean 9.1 mm (range 2-25 mm). There were few side-effects requiring intervention. Twelve patients underwent surgery due to ektropion during follow-up. In 101 patients, treatment of the tumour resulted in conjunctival growth on the skin side, which required correcting operations in 28 patients. Three recurrences have occurred. CONCLUSION: Cryosurgery is an effective treatment modality for eyelid basal cell carcinomas, resulting in few recurrences and good cosmetic and functional outcomes at a low cost.

Vitamin D status in psoriasis patients during different treatments with phototherapy.

BACKGROUND: Phototherapy (broadband UVB (BUVB), narrowband UVB (NBUVB) and heliotherapy) is commonly used treatment modalities for widespread psoriasis. Vitamin D3, cholecalciferol, is produced in the epidermis by ultraviolet radiation (290-315 nm) of 7-dehydrocholesterol. 25-hydroxyvitamin D [25(OH)D], and 1,25-dihydroxyvitamin D [1,25(OH)(2)D] are the major circulating metabolites. Sun exposure is the strongest factor influencing 25(OH)D. The similar wavelength spectrum of UVB responsible for D vitamin synthesis (BUVB, 280-315 nm) has been successfully used for years to treat psoriasis. PURPOSE: The aim was: (1) To increase the knowledge about the effects of phototherapy on vitamin D production during treatment of psoriasis. (2) To examine if there were differences between the effect of BUVB, NBUVB and heliotherapy on vitamin D synthesis in psoriasis patients. METHODS: Serum concentrations of 25(OH)D, 1,25(OH)(2)D, PTH, calcium and creatinine, measured before and after phototherapy in white Caucasian patients with moderate to severe active plaque psoriasis, were aggregated from three studies. RESULTS: Psoriasis improved in all patients, with a reduction in PASI ((Psoriasis Area and Severity Index) score of about 75% on all regimes. Serum 25(OH)D increased and PTH decreased after the phototherapy. The increase in 25(OH)D was higher in the BUVB treated patients compared with NBUVB. There was no correlation between the dose of UVB and the increase of 25(OH)D. CONCLUSION: UVB and heliotherapy improved the psoriasis score, increased the serum 25(OH)D levels and reduced the serum PTH concentrations. Vitamin D production in psoriasis patients increased less with NBUVB than with BUVB phototherapy.