SummarySocioeconomic status (SES) is associated with cutaneous malignant melanoma (CMM) in Northern Europe, despite equal access to health care. SES per se is not responsible for this association, which must be ascribed to important risk factors for CMM such as intermittent ultraviolet radiation (UVR) exposure, and screening for CMM possibly owing to a greater knowledge and understanding of CMM. Our review of the literature showed that high SES is associated with increased risk of CMM, thinner tumours, increased survival and decreased mortality from CMM -the latter shown among women, and in recent studies also among men. There is evidence that high SES is associated with sun holidays, whereas low SES is associated with the use of sunbeds. Findings suggest that high SES is associated with the use of physicians and dermatologists for marks and moles, possibly owing to more knowledge and better understanding of CMM. We conclude that there has been a true increase in CMM incidence among high SES individuals in Northern Europe probably due to past intense intermittent UVR exposure, especially in connection with sun holidays. However, the increased risk of CMM and a better outcome of CMM in high SES individuals may also be conditioned by frequent recourse to physicians, which may be ascribed to more knowledge and better understanding of CMM, although more studies on this subject are warranted. Thicker CMM tumours and increased CMM mortality among low SES individuals in recent decades may reflect exposure to intermittent UVR, such as the use of sunbeds, as well as delayed diagnosis.What's already known about this topic?• Socioeconomic status (SES) is associated with cutaneous malignant melanoma (CMM) in Northern Europe despite equal access to health care.• It is not SES per se but risk factors for CMM that are responsible for this association.What does this study add?• Intermittent ultraviolet radiation exposure from sun holidays, and possibly more knowledge and better understanding of CMM may be responsible for the increased incidence registered and decreased mortality from CMM among high SES individuals.A positive association of socioeconomic status (SES) with risk of cutaneous malignant melanoma (CMM) has been well known for many years. However, SES per se is not responsible for this association, but must be ascribed to certain risk factors for CMM that are closely associated with SES.Intermittent ultraviolet radiation (UVR) exposure is considered a major risk factor for CMM.

IMPORTANCE UV radiation (UVR) exposure is the primary environmental risk factor for developing cutaneous malignant melanoma (CMM). OBJECTIVE To measure changes in sun behavior from the first until the third summer after the diagnosis of CMM using matched controls as a reference. DESIGN, SETTING, AND PARTICIPANTS Three-year follow-up, observational, case-control study performed from May 7 to September 22, 2009, April 17 to September 15, 2010, and May 6 to July 31, 2011, at a university hospital in Denmark of 21 patients with CMM and 21 controls matched to patients by sex, age, occupation, and constitutive skin type participated in the study. Exposure to UVR was assessed the first and second summers (n=20) and the first and third summers (n=22) after diagnosis. Data from 40 participants were analyzed. MAIN OUTCOMES AND MEASURES Exposure to UVR was assessed by personal electronic UVR dosimeters that measured time-related UVR in standard erythema dose (SED) and corresponding sun diaries (mean, 74 days per participant each participation year). RESULTS Patients' daily UVR dose and UVR dose in connection with various behaviors increased during follow-up (quantified as an increase in daily UVR dose each year; all days: mean, 0.3 SED; 95% CI, 0.05-0.5 SED; days with body exposure: mean, 0.6 SED; 95% CI, 0.07-1.2 SED; holidays: mean, 1.2 SED; 95% CI, 0.3-2.1 SED; days abroad: 1.9 SED; 95% CI, 0.4-3.4 SED; and holidays with body exposure: mean, 2.3 SED; 95% CI, 1.1-3.4 SED). After the second year of follow-up, patients' UVR dose was higher than that of controls, who maintained a stable UVR dose. No difference was found between groups in the number of days with body exposure or the number of days using sunscreen in the second and third years of follow-up. CONCLUSIONS AND RELEVANCE Our findings suggest that patients with CMM do not maintain a cautious sun behavior in connection with an increase in UVR exposure, especially on days with body exposure, when abroad, and on holidays.

Patients with CMM limited their UVR dose on days with body exposure, and by using sunscreen further reduced UVR reaching the skin, although only immediately after diagnosis.

Topical photodynamic therapy (PDT) is used for various skin disorders, and selective targeting of specific skin structures is desirable. The objective was to assess accumulation of PpIX fluorescence and photobleaching within skin layers using different photosensitizers and light sources. Normal human skin was tape-stripped and incubated with 20% methylaminolevulinate (MAL) or 20% hexylaminolevulinate (HAL) for 3 h. Fluorescence microscopy quantified PpIX accumulation in epidermis, superficial, mid and deep dermis, down to 2 mm. PpIX photobleaching by light-emitting diode (LED, 632 nm, 18 and 37 J/cm(2)), intense pulsed light (IPL, 500-650 nm, 36 and 72 J/cm(2)) and long-pulsed dye laser (LPDL, 595 nm, 7.5 and 15 J/cm(2)) was measured using fluorescence photography and microscopy. We found higher PpIX fluorescence intensities in epidermis and superficial dermis in HAL-incubated skin than MAL-incubated skin (P < 0.001). In mid and deep dermis, fluorescence intensities were higher (37%) in HAL-treated skin than MAL-treated skin, although not significant (P = ns). At skin surface, photobleaching was significantly higher (90-98%) after LED illumination (18 and 37 J/cm²) than IPL (29-53%, 36 and 72 J/cm²) and LPDL (43-62%, 7 and 15 J/cm²) (P < 0.001). Within the skin, photobleaching was steady from epidermis to deep dermis by LED illumination (37 J/cm², P = ns), but declined from epidermis to mid and deep dermis for IPL-treated skin and LPDL-treated skin (IPL 72 J/cm²: 26-15%; LPDL 15 J/cm²: 37-23%) (P < 0.04). Clinically, erythema correlated linearly with MAL and HAL-induced photobleaching (r² = 0.175, P < 0.001). In conclusion, selective PpIX accumulation indicates HAL as an alternative to MAL for epidermal-targeted PDT. In clinically relevant doses, PpIX photobleaching throughout the skin was more profound following LED than LPDL and IPL exposure.