Martin Gillstedt

Predictors of pain associated with photodynamic therapy: a retrospective study of 658 treatments.

Pain is the most common side-effect of photodynamic therapy (PDT). Our main objective was to identify pain predictors in PDT. In total, we performed 658 treatments on 377 patients at our department during 2004. Larger sized treatment areas were the strongest pain predictor, and actinic keratoses were more painful to treat than basal cell carcinomas and Bowens disease. The most sensitive areas to treat were the face and scalp. Gender and age did not influence pain. Although treatment outcome was not our primary objective, 62% of 95 superficial basal cell carcinomas that were followed for 3 years showed complete clearance. Also, perforation of nodular basal cell carcinomas did not lead to better clinical results. In conclusion, the size of the treatment area, the diagnosis and the lesion location influence pain during PDT. Nevertheless, there is a large variance in visual analogue scale assessment within each group, thereby limiting the ability to predict pain.

Smartphone Teledermoscopy Referrals: A Novel Process for Improved Triage of Skin Cancer Patients

In this open, controlled, multicentre and prospective observational study, smartphone teledermoscopy referrals were sent from 20 primary healthcare centres to 2 dermatology departments for triage of skin lesions of concern using a smartphone application and a compatible digital dermoscope. The outcome for 816 patients referred via smartphone teledermoscopy was compared with 746 patients referred via the traditional paper-based system. When surgical treatment was required, the waiting time was significantly shorter using teledermoscopy for patients with melanoma, melanoma in situ, squamous cell carcinoma, squamous cell carcinoma in situ and basal cell carcinoma. Triage decisions were also more reliable with teledermoscopy and over 40% of the teledermoscopy patients could potentially have avoided face-to-face visits. Only 4 teledermoscopy referrals (0.4%) had to be excluded due to poor image quality. Smartphone teledermoscopy referrals allow for faster and more efficient management of patients with skin cancer as compared to traditional paper referrals.

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.

Unexpected loss of contact allergy to aluminium induced by vaccine.

Background. In studies in Gothenburg, Sweden, in the 1990s of an aluminium hydroxide‐adsorbed pertussis toxoid vaccine, 745 of ∼76 000 vaccinated children developed long‐lasting itchy subcutaneous nodules at the vaccination site. Of 495 children with itchy nodules patch tested for aluminium allergy, 376 (76%) were positive.

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.

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.

Biofilm formation on nanostructured hydroxyapatite‐coated titanium

Biofilm formation on medical devices is a common cause of implant failure, especially regarding implants that breach the epithelial tissue, so-called transcutaneous implants. Nanotechnology and the development of new nanomaterials have given the opportunity to design nanotextured implant surfaces. Such surfaces have been studied using various in vitro methods showing that nanosized features strongly benefit bone cell growth. However, little is known on how nanostructured features affect biofilm formation. The aim of this study was therefore to examine the shape- and chemical-dependent effect of a nanostructured hydroxyapatite (HA) coating on the degree of Staphylococcus epidermidis biofilm formation. Three different types of nanosized HA particles having different shapes and calcium to phosphate ratios were compared to uncoated turned titanium using safranin stain in a biofilm assay and confocal laser scanning microscopy (CLSM) for assessment of biofilm biomass and bacterial volume, respectively. No difference in biofilm biomass was detected for the various surfaces after 6 h incubation with S. epidermidis. Additionally, image analysis of CLSM Z-stacks confirmed the biofilm assay and showed similar results. In conclusion, the difference in nanomorphology and chemical composition of the surface coatings did not influence the adhesion and biofilm formation of S. epidermidis.

Aminolevulinic acid and methyl aminolevulinate equally effective in topical photodynamic therapy for non‐melanoma skin cancers

Topical photodynamic therapy (PDT) is an effective treatment for superficial non‐melanoma skin cancers. Two prodrugs, 5‐aminolevulinic acid (ALA) and methyl aminolevulinate (MAL), are available for clinical use. There is, however, a lack of studies comparing the clinical effectiveness of these two prodrugs.

Merkel cell carcinoma incidence is increasing in Sweden

Merkel cell carcinoma (MCC) is a rare aggressive neuroectodermal skin cancer with a high recurrence rate and a high mortality rate. Risk factors for MCC are reported to include high age, UV exposure, Caucasian skin type and immunosuppression. The incidence is reported to be increasing.

Methotrexate treatment and risk for cutaneous malignant melanoma: a retrospective comparative registry-based cohort study

Methotrexate (MTX) is frequently used as an immunosuppressive drug in inflammatory diseases. It is controversial and it has not been thoroughly investigated whether MTX increases the risk of cutaneous malignant melanoma (CMM).