Inger Rosdahl

A randomized multicenter study to compare two treatment regimens of topical methyl aminolevulinate (Metvix®)-PDT in actinic keratosis of the face and scalp

Photodynamic therapy (PDT) with topical methyl aminolevulinate (MAL) administered in two treatment sessions separated by 1 week is an effective treatment for actinic keratoses. This open prospective study compared the efficacy and safety of MAL-PDT given as a single treatment with two treatments of MAL-PDT 1 week apart. Two hundred and eleven patients with 413 thin to moderately thick actinic keratoses were randomized to either a single treatment with PDT using topical MAL (regimen I; n=105) or two treatments 1 week apart (regimen II; n=106). Each treatment involved surface debridement, application of Metvix cream (160 mg/g) for 3 h, followed by illumination with red light using a light-emitting diode system (peak wavelength 634+/-3 nm, light dose 37 J/cm2). Thirty-seven lesions (19%) with a non-complete response 3 months after a single treatment were re-treated. All patients were followed up 3 months after the last treatment. A total of 400 lesions, 198 initially treated once and 202 treated twice, were evaluable. Complete response rate for thin lesions after a single treatment was 93% (95% CI=87-97%), which was similar to 89% (82-96%) after repeated treatment. Response rates were lower after single treatment of thicker lesions (70% (60-78%) vs 84% (77-91%)), but improved after repeated treatment (88% (82-94%)). The conclusion of this study is that single treatment with topical MAL-PDT is effective for thin actinic keratosis lesions; however, repeated treatment is recommended for thicker or non-responding lesions.

Photodynamic therapy of actinic keratosis at varying fluence rates: assessment of photobleaching, pain and primary clinical outcome

Background  Although photodynamic therapy (PDT) is becoming an important treatment method for skin lesions such as actinic keratosis (AK) and superficial basal cell carcinoma, there are still discussions about which fluence rate and light dose are preferable. Recent studies in rodents have shown that a low fluence rate is preferable due to depletion of oxygen at high fluence rates. However, these results have not yet been verified in humans.

Effect of Pregnancy on Survival in Women With Cutaneous Malignant Melanoma

PURPOSE An adverse influence of pregnancy on the risk of death in women with cutaneous melanoma was suggested historically by anecdotal reports. Previous studies included small numbers of women observed for short periods. METHODS Using data from the Swedish National and Regional Registries, we performed a retrospective cohort study of all Swedish women who were diagnosed with cutaneous melanoma during their reproductive period, from January 1, 1958, to December 31, 1999. The relationship between pregnancy status at the diagnosis of melanoma and overall survival was examined in multivariable proportional-hazards models. RESULTS The cohort comprised 185 women (3.3%) diagnosed with melanoma during pregnancy and 5,348 (96.7%) women of the same childbearing age diagnosed with melanoma while not pregnant. There was no statistically significant difference in overall survival between pregnant and nonpregnant groups (log-rank chi(2)1[r] = 0.84, P = .361). Pregnancy status at the time of diagnosis of melanoma was not related to survival in a multivariable Cox model in the 2,101 women (hazard ratio for death in the pregnant group was 1.08; 95% CI, 0.60 to 1.93). In the multivariable analysis, pregnancy status after diagnosis of melanoma was not a significant predictor of survival (hazard ratio for death in women who had pregnancy subsequent to the diagnosis of melanoma was 0.58; 95% CI, 0.32 to 1.05). CONCLUSION The survival of pregnant women with melanoma is not worse than the survival of nonpregnant women with melanoma. Pregnancy subsequent to the diagnosis of primary melanoma was not associated with an increased risk of death.

Important factors for pain during photodynamic therapy for actinic keratosis

Photodynamic therapy (PDT) is an efficient treatment for actinic keratosis. A common problem, however, is pain. The aim of this study was to investigate pain during PDT for actinic keratosis. The possibility of using capsaicin cream for pain relief was also assessed. Pain was investigated during aminolaevulinic acid PDT in 91 patients. Size, redness, scaling and induration of the lesions were recorded. Maximum pain during treatment was registered, using a visual analogue scale (0-10). The pain-reducing efficacy of capsaicin was tested in a pilot study in six patients (10 lesions). These patients were pre-treated with capsaicin cream for one week before commencing PDT. Pain was found to be normally distributed around a mean value of visual analogue scale 4.6. Larger lesions gave more pain (p=0.001). The redness of the actinic lesions was found to be related to PDT-induced pain (p=0.01), the reduction of actinic area (p=0.007), and the cure rate (p=0.01). The redder the actinic area, the better the treatment outcome and the more pain experienced. Patients with the largest reduction in the actinic area experienced more pain (p=0.053). The most important factors for presence of pain seem to be the size and the redness of the lesion. No significant pain relief was experienced after pre-treatment with capsaicin.

Regional distribution of common and dysplastic naevi in relation to melanoma site and sun exposure. A case-control study.

The frequency of melanoma (CMM), and of common and dysplastic naevi (CN and DN) in areas of skin chronically, intermittently and rarely exposed to UV light was investigated in 121 melanoma patients (30–50 years) and 310 controls. Both cases and controls had significantly more CN in intermittently exposed areas than in areas chronically or rarely exposed. The ratio of observed to expected number of CMM was also highest in intermittently exposed skin (1.3 compared to 0.8 in chronically exposed and 0.5 in rarely exposed areas). Thus, intermittent UV exposure seems to have the most potent naevo-genic‘ as well as carcinogenic effect on melanocytes. Nineteen per cent of controls and 56% of cases had naevi fulfilling the clinical criteria for DN. The distribution pattern of DN was clearly different from that of CN and does not accord with the idea that UV light is a major aetiological factor for DN. The probability of CMM significantly increased with the degree of relative clustering of CN (p<0.05) and of DN (p<0.01). This co-variation of naevi and CMM over the body surface might be the result of the local insults to the melanocyte system caused by UV light and/or to the fact that naevi are precursor lesions of CMM.

PREVALENCE OF COMMON AND DYSPLASTIC NAEVI IN A SWEDISH POPULATION

The naevus profile was examined in a Swedish population that was randomly selected from a census file. The participation rate was considered high at 82%. The number of common naevi (CN) and the prevalence of dysplastic naevi (DN) were investigated in 379 subjects (aged 30–50 years). The mean total body count of CN2 mm was 67 (range 1–300). As many as 22% of the population had 100 naevi or more and only 18% had less than 25. The counts were not influenced by age or sex. DN were diagnosed clinically in 18% (CI 14–22%) of the subjects and histologically in 8% (CI 5–11%). Subjects with dysplastic naevi had a significantly larger number of common naevi and a more sun‐sensitive skin type than subjects without DN, P<0.001.

Ultraviolet A and B affect human melanocytes and keratinocytes differently. A study of oxidative alterations and apoptosis

Abstract:  Ultraviolet (UV) radiation is an etiologic agent for malignant melanoma and non‐melanoma skin cancer, but the spectral range responsible for tumor induction is still to be elucidated. In this study, we compared effects of UVA and UVB irradiation on normal human melanocytes (MCs) and keratinocytes (KCs) in vitro. We demonstrate that UVA irradiation induces immediate loss of reduced glutathione (GSH) in both MCs and KCs. Exposure to UVA also causes reduced plasma membrane stability, in both cell types, as estimated by fluorescein diacetate retention and flow cytometry. Furthermore, we noted reduction in proliferation and higher apoptosis frequency 24 h after UVA irradiation. UVB irradiation of KCs caused instant reduction of reduced GSH and impaired plasma membrane stability. We also found decline in proliferation and increased apoptosis after 24 h. In MCs, on the other hand, UVB had no effect on GSH level or plasma membrane stability, although increased apoptotic cell death and reduced proliferation was detected. In summary, MCs and KCs showed similar response towards UVA, while UVB had more pronounced effects on KCs as compared to MCs. These results might have implications for the induction of malignant melanoma and non‐melanoma skin cancer.

Sun-related behaviour and melanoma awareness among Swedish university students.

The relationship between knowledge, attitude and sun-related behaviour among Swedish students was examined in the present study. A total of 296 of 305 questionnaires, distributed among university students (medical school and economy programme) were analysed (157 men, 139 women, mean age 24 years). The percentage of students sunbathing with the intention of getting a tan was 75%. Thirteen per cent reported having experienced at least one painful sunburn every year and 93% stated at least one burn during the last ten years. The majority of the students had used a sun bed, 12% more than ten times during the last year. Subjects with high frequency of sun bed use also scored high on sunbathing and sunburns. Significantly more women (70%) than men (51%) used sunscreen. The overall knowledge of melanoma was high. No difference in knowledge was found between the high- and low-exposure group. Medical students scored higher on knowledge than economy students, but did not differ in exposure score. Our findings reveal an excessive sun exposure among university students. A high level of knowledge of risk does not lead to a sun-protective behaviour. Future preventative campaigns targeting young people must focus on strategies to change attitudes towards tanning as being healthy and attractive.

Societal Cost of Skin Cancer in Sweden in 2005

Skin cancer is one of the most rapidly increasing cancers among the Swedish population and a significant cause of illness and death. This study aims to estimate the total societal cost of skin cancer in Sweden for 2005, using a prevalence-based cost-of-illness approach. The total cost of skin cancer was estimated at euro 142.4 million (euro 15/inhabitant), of which euro 79.6 million (euro 8/inhabitant) was spent on health services and euro 62.8 million (euro 7/inhabitant) was due to loss of production. The main cost driver was resource utilization in outpatient care, amounting to 42.2% of the total cost. Melanoma was the most costly skin cancer diagnosis. Non-melanoma skin cancer was, however, the main cost driver for health services alone. For the future it is important to establish effective preventive measures to avoid increasing costs and suffering caused by skin cancer.

Increasing incidence of cutaneous malignant melanoma in children and adolescents 12-19 years of age in Sweden 1973-92.

One-hundred-and-seventy-seven cases of cutaneous malignant melanoma were reported to the Swedish National Cancer Registry in subjects below the age of 20 during the period 1973-92. One-hundred-and-fifty-four (87%) were re-examined histologically, and the original diagnosis of primary cutaneous malignant melanoma was verified in 88%. The age-specific mean annual incidence rate increased to 0.5/100,000 in 1983-92 from 0.2/100,000 in 1973-82. Cutaneous malignant melanoma remained extremely rare in children below the age of 12, where only two cases were found. In subjects aged 12-19, the incidence doubled to 93 cases in the second 10-year period compared to 41 in the first. In boys, most of the melanomas occurred on the trunk, and, in girls, on the legs. Sixty-three percent of the melanomas were of the superficial spreading type, which also was the most rapidly increasing type of melanoma. These results emphasize the importance of surveillance and intensified preventive measures in protecting children and adolescents from the harmful effects of excessive exposure to the sun.