Is an online skin cancer toolkit an effective way to educate primary care physicians about skin cancer diagnosis and referral?

BACKGROUND: Skin disorders account for over 20% of GP consultations. Half of dermatology referrals to secondary care are for skin lesions, but only 12% of urgent skin cancer referrals are deemed appropriate. Suitably designed online learning resources may positively impact GP confidence in the recognition of skin cancer and improve patient outcomes. OBJECTIVE: This study evaluated the impact of a national, online, skin cancer recognition toolkit on GP confidence and knowledge in diagnosing skin cancers and referral behaviour to secondary care. METHODS: The toolkit, consisting of a referral decision aid, lesion recognition resource, clinical cases and a quiz, was launched in March 2012. Website usage statistics and online focus groups were used to assess the usability of the website and perceived changes in behaviour. The impact of the toolkit was assessed using national skin cancer referral data, cross-sectional questionnaires and urgent skin cancer referral data to two NHS trusts. RESULTS: The toolkit was accessed by 20% of GPs in England from 20th March to 31st October 2012; spending a mean of over 5 minutes each, with over 33% return users. A survey revealed that the toolkit improved perceptions of skin cancer training and self-reported knowledge about skin cancer referral pathways. Analysis of referral patterns did not identify an impact of the toolkit on number or appropriateness of urgent skin cancer referrals in the eight months following the launch of the website. Online focus groups confirmed the usefulness of the resource and suggested a positive influence on knowledge and referral behaviour. CONCLUSION: The skin cancer toolkit is an accessible online learning resource for improving confidence with skin cancer referral amongst GPs. Although we were unable to identify any immediate changes in skin cancer diagnoses or appropriate referral behaviours, research is required to evaluate its longer term effects on outcomes.

A surveillance model for skin cancer in organ transplant recipients: a 22-year prospective study in an ethnically diverse population.

Skin cancer is a frequent complication of organ transplantation. Current guidelines advise specialist skin surveillance but there are limited data on how these should be implemented. This study determines overall burden of cancer and relevant intervals for strategic surveillance in an ethnically diverse transplant population. Prospective data on time to first and subsequent cancers and cumulative burden with respect to defined risk factors were analyzed in a cohort of 1010 patients in a UK center over 22 years. Among 931 individuals transplanted >6 months (mean 10.3 years), 1820 skin cancers occurred in 267 (29%) individuals and were multiple in 66%. Cumulative incidence at 5, 10, 20 and 30 years was 11%, 25%, 54% and 74%, with median time to second, third and fourth cancers of 24, 14.7 and 8.4 months, respectively. Tumors were overwhelmingly squamous and basal cell carcinomas (73% and 24%, respectively). Skin phototype, ultraviolet radiation exposure, age at transplant and duration of transplant were significant risk predictors and were used to construct clinically relevant surveillance intervals. This study provides a comprehensive, prospective analysis of skin cancer morbidity and risk in an ethnically diverse transplant population from which we derive an evidence-based skin cancer surveillance program.

Synchronous melanoma and renal carcinoma: a clinicopathological study of five cases.

An increased frequency of renal carcinoma in men with melanoma has been reported in population based-studies. We report the clinicopathological findings of five cases of synchronous renal cell carcinoma (RCC), identified after routine radiological staging for cutaneous malignant melanoma (MM) between October 2006 and October 2008. The five patients (three men and two women, with a mean age of 62.4 years), presented with six melanomas of varying subtypes. The mean Breslow thickness was 1.87 mm. There was no family history of cancer in any of the cases. Routine radiological staging identified a mass arising from the left kidney in three cases and the right kidney in two cases. All patients underwent radical nephrectomy, and histology in each case confirmed RCC of the clear-cell subtype. Mean follow-up was 3 years. Although the simultaneous occurrence of RCC and MM may be coincidental, there are several plausible aetiological links. Further analysis of the synchronous occurrence of MM and renal cancer may provide therapeutic insights into these two important tumours.

A common polymorphism acts as an intragenic modifier of mutant p53 behaviour.

The p73 protein, a homologue of the tumour-suppressor protein p53, can activate p53-responsive promoters and induce apoptosis in p53-deficient cells. Here we report that some tumour-derived p53 mutants can bind to and inactivate p73. The binding of such mutants is influenced by whether TP53 (encoding p53) codon 72, by virtue of a common polymorphism in the human population, encodes Arg or Pro. The ability of mutant p53 to bind p73, neutralize p73-induced apoptosis and transform cells in cooperation with EJ-Ras was enhanced when codon 72 encoded Arg. We found that the Arg-containing allele was preferentially mutated and retained in squamous cell tumours arising in Arg/Pro germline heterozygotes. Thus, inactivation of p53 family members may contribute to the biological properties of a subset of p53 mutants, and a polymorphic residue within p53 affects mutant behaviour.

Reversal of UVA skin photosensitivity and DNA damage in kidney transplant recipients by replacing azathioprine.

Azathioprine is associated with enhanced skin photosensitivity to ultraviolet A (UVA) and leads to incorporation of 6-thioguanine (6-TG) into DNA of dividing cells. Unlike canonical DNA, 6-TG DNA is damaged by UVA, which comprises more than 90% of the ultraviolet reaching earth. Skin photosensitivity to UVA and UVB was measured in 48 kidney transplant patients immunosuppressed either by azathioprine (n = 32) or mycophenolate (n = 16). In 23 patients, azathioprine was subsequently replaced by mycophenolate and skin photosensitivity, DNA 6-TG content in peripheral blood mononuclear cells, and susceptibility to UVA-induced DNA damage were monitored for up to 2 years. The mean minimal erythema dose to UVA on azathioprine was twofold lower than on mycophenolate. Three months after replacing azathioprine by mycophenolate mofetil, the minimal erythema dose to UVA had increased from 15 to 25 J/cm(2) (p < 0.001) accompanied by reduced DNA 6-TG content. P53 protein expression in irradiated skin indicated reduced susceptibility to UVA-induced DNA damage. 6-TG DNA in peripheral blood mononuclear cells remained measurable for over 2 years. Replacing azathioprine selectively reduced the skin photosensitivity to UVA, attenuated UVA-induced skin DNA damage, and is likely based on incorporated 6-TG in DNA.

Sensitivity to sunburn is associated with susceptibility to ultraviolet radiation-induced suppression of cutaneous cell-mediated immunity.

Skin cancer incidence is highest in white-skinned people. Within this group, skin types I/II (sun sensitive/tan poorly) are at greater risk than skin types III/IV (sun tolerant/tan well). Studies in mice demonstrate that ultraviolet radiation (UVR)-induced suppression of cell-mediated immune function plays an important role in the development of skin cancer and induces a susceptibility to infectious disease. A similar role is suspected in humans, but we lack quantitative human data to make risk assessments of ambient solar exposure on human health. This study demonstrates that ambient levels of solar UVR, typically experienced within 1 h of exposure to noonday summer sunlight, can suppress contact hypersensitivity (CHS) responses in healthy white-skinned humans in vivo (n = 93). There was a linear relationship between increase in erythema and suppression of CHS (P < 0.001), and a moderate sunburn (two minimal erythema doses [2 MED]) was sufficient to suppress CHS in all volunteers by 93%. However, a single suberythemal exposure of either 0.25 or 0.5 MED suppressed CHS responses by 50 and 80%, respectively, in skin types I/II, whereas 1 MED only suppressed CHS by 40% in skin types III/IV. The two- to threefold greater sensitivity of skin types I/II for a given level of sunburn may play a role in their greater sensitivity to skin cancer.

Expression of DNA mismatch repair proteins and MSH2 polymorphisms in nonmelanoma skin cancers of organ transplant recipients.

BACKGROUND: Organ transplant recipients (OTRs) have an increased risk of skin cancer. Treatment with azathioprine, commonly used in post-transplant immunosuppressive regimens, results in incorporation of 6-thioguanine (6-TG) into DNA. Mismatch repair (MMR)-defective cells are resistant to killing by 6-TG. Azathioprine exposure confers a survival advantage on MMR-defective cells, which are hypermutable and may therefore contribute to azathioprine-related nonmelanoma skin cancer, a phenomenon we have previously demonstrated in transplant-associated sebaceous carcinomas. The MSH2 protein is an important component of DNA MMR. The -6 exon 13 T>C MSH2 polymorphism is associated with impaired MMR, drug resistance and certain cancers. OBJECTIVES: To investigate (i) whether loss of MMR protein expression and microsatellite instability are over-represented in squamous cell carcinomas (SCCs) from OTRs on azathioprine compared with SCCs from immunocompetent patients, and (ii) whether the MSH2 -6 exon 13 polymorphism is over-represented in OTRs with skin cancer on azathioprine. METHODS: (i) Immunohistochemical staining was used to assess expression of the MMR proteins MSH2 and MLH1 in cutaneous SCCs from OTRs on azathioprine and from immunocompetent patients. (ii) Blood samples from OTRs on azathioprine with and without skin cancer were genotyped for the -6 exon 13 MSH2 polymorphism. RESULTS: (i) MSH2 and MLH1 protein expression was not altered in SCCs from OTRs on azathioprine and there was no difference in expression between SCCs from OTRs and immunocompetent patients. (ii) There was no association between MSH2 polymorphism genotype frequency and OTR skin cancer status. CONCLUSIONS: Despite previous findings in transplant-associated sebaceous carcinomas, defective MMR and the -6 exon 13 MSH2 polymorphism are unlikely to play a significant role in the development of SCC in OTRs on azathioprine.

PTCH mutations in basal cell carcinomas from azathioprine-treated organ transplant recipients.

The immunosuppressant azathioprine is used to prevent graft rejection after organ transplantation. To investigate whether azathioprine-associated mutagenesis contributes to the high incidence of skin tumours in organ transplant recipients (OTRs), we analysed PTCH gene mutations in 60 basal cell carcinomas (BCC); 39 from OTRs receiving azathioprine and 21 from individuals never exposed to azathioprine. PTCH was mutated in 55% of all tumours, independent of azathioprine treatment. In both the azathioprine and non-azathioprine groups, transitions at dipyrimidine sequences, considered to indicate mutation by ultraviolet-B radiation, occurred frequently in tumours from chronically sun-exposed skin. In BCC from non-sun-exposed skin of azathioprine-treated patients, there was an over-representation of unusual G:C to A:T transitions at non-dipyrimidine sites. These were exclusive to the azathioprine-exposed group and all in the same TGTC sequence context at different positions within PTCH. Meta-analysis of 247 BCCs from published studies indicated that these mutations are rare in sporadic BCC and had never previously been reported in this specific sequence context. This study of post-transplant BCC provides the first indication that azathioprine exposure may be associated with PTCH mutations, particularly in tumours from non-sun-exposed skin.

Melanoma in organ transplant recipients: clinicopathological features and outcome in 100 cases.

Organ transplant recipients have a higher incidence of melanoma compared to the general population but the prognosis of this potentially fatal skin cancer in this group of patients has not yet been established. To address this, we undertook a multicenter retrospective analysis to assess outcome for 100 melanomas (91 posttransplant and 9 pretransplant) in 95 individuals. Data were collected in 14 specialist transplant dermatology clinics across Europe belonging to the Skin Care in Organ Transplant Patients, Europe (SCOPE) Network, and compared with age, sex, tumor thickness and ulceration status-matched controls from the American Joint Committee on Cancer (AJCC) melanoma database. Outcome for posttransplant melanoma was similar to that of the general population for T1 and T2 tumors (< or = 2 mm thickness); but was significantly worse for T3 and T4 tumors (> 2 mm thickness); all nine individuals with a pretransplant melanoma survived without disease recurrence following organ transplantation. These data have implications for both cutaneous surveillance in organ transplant recipients and management of transplant-associated melanoma.

Azathioprine treatment photosensitizes human skin to ultraviolet A radiation.

BACKGROUND: Azathioprine is used to treat a variety of conditions and to prevent graft rejection in organ transplant recipients (OTRs). OBJECTIVES: To investigate clinically our previous finding that azathioprine metabolites interact with ultraviolet (UV) A radiation to form promutagenic oxidative DNA damage and to determine whether this may be causal or contributory to the development of excess skin cancers post-transplantation. METHODS: The clinical corollary of these data were investigated. Five patients were recruited and the minimal erythema dose (MED) for UVB, UVA and solar-simulated radiation (SSR) was determined for each person before, and at least 12 weeks after, starting azathioprine therapy. RESULTS: In all five patients azathioprine treatment was associated with an increased UVA and SSR sensitivity of the skin and a significant reduction in MEDs for UVA and SSR. We found no change in UVB-induced erythema or MED. In addition, we found that DNA from the skin of patients on azathioprine contains 6-thioguanine (6-TG). CONCLUSIONS: Our findings confirm the presence of DNA 6-TG in the skin of those taking therapeutic doses of azathioprine and provide support for the hypothesis that DNA damage occurs when DNA 6-TG interacts with UVA, resulting in abnormal cutaneous photosensitivity.

Beta-papillomaviruses and psoriasis: an intra-patient comparison of human papillomavirus carriage in skin and hair.

BACKGROUND: Human papillomaviruses (HPVs) of the beta genus (beta-PV), especially HPV5 and HPV36, are proposed to play a pathogenic role in psoriasis, but many previous studies have failed to control for potential confounders, including treatment. OBJECTIVES: To re-examine the relationship between beta-PV and psoriasis addressing limitations present in previous studies and analyse intra-patient concordance for carriage of HPV. METHODS: Plucked eyebrow hairs and forearm skin scrapes were collected from 20 newly diagnosed, previously untreated adult patients with psoriasis and 23 normal controls. A combination of type-specific and degenerate polymerase chain reaction methods was used to achieve comprehensive HPV DNA detection. RESULTS: The prevalence of HPV in hair and skin from psoriasis patients was higher than in controls (83.3% vs. 46.7%, respectively, P < 0.03 corrected for age and clustering). HPV5 or HPV36 were not over-represented. The profile of diverse beta-PV types was comparable in the two groups. Intra-patient concordance for HPV DNA at separate sites was high (P < 0.00001). CONCLUSIONS: Our data do not support a specific causal role for HPV5 or HPV36 in psoriasis, but suggest that psoriatic skin may be more permissive for viral presence than normal skin. High intra-patient concordance for specific HPV types at separate sites, together with the ubiquity of HPV DNA in normal human skin, suggests that an individual becomes colonized with a particular beta-PV profile presumably to the exclusion of other types. To what extent this HPV profile is then causal in the subsequent development of hyperproliferative skin disease is unknown.

p53 mutations implicate sunlight in post-transplant skin cancer irrespective of human papillomavirus status.

Mutations in p53 were detected in 11/23 (48%) of non melanoma skin cancers in renal allograft recipients and in 5/8 (63%) of sporadic tumours from immune competent patients. 9/12 (75%) of mutations in transplant patients and all 5 mutations in non transplant tumours were consistent with damage caused by ultraviolet (u.v.) irradiation. DNA sequences, predominantly of the epidermodysplasia verruciformis (EV) subgroup, were detected in 9/23 (39%) of transplant tumours and in 2/8 (25%) of eight non-transplant tumours. There was no relationship between HPV status and p53 mutation, HPV DNA being present in 5/16 (31%) of tumours with p53 mutation and 6/15 (40%) of tumours lacking p53 mutation. These data are consistent with an important role for sunlight in the development of post-transplant skin cancer, and with limited functional data suggesting that E6 proteins of the cutaneous and EV-related papillomaviruses do not target p53 for ubiquitin-mediated degradation.

The heritability of polymorphic light eruption.

Polymorphic light eruption is classified as an acquired idiopathic photodermatosis, yet it appears to cluster in families, suggesting a possible genetic component. In this study, we assess the heritability of polymorphic light eruption using the classical twin model. Polymorphic light eruption was investigated by a nurse-administered questionnaire in a sample of 420 pairs of adult female twins from St Thomas' Hospital UK Adult Twin Registry, including 119 monozygotic and 301 dizygotic pairs. Probandwise concordance for the presence and absence of disease was calculated and the heritability of polymorphic light eruption assessed by a quantitative genetic model fitting approach using Mx software. The prevalence of polymorphic light eruption was 21% and 18% in monozygotic and dizygotic twins, respectively. A family history of polymorphic light eruption in first-degree relatives (not including the cotwin) was present in 12% of affected twin pairs (where at least one twin had polymorphic light eruption) compared with 4% of unaffected twin pairs, providing evidence of familial clustering (p < 0.0001). The probandwise concordance for polymorphic light eruption was higher in monozygotic (0.72) than in dizygotic twin pairs (0.30), indicating a strong genetic effect. Quantitative genetic modeling found that a model comprising additive genetic (A) and unique environmental (E) factors provided the most parsimonious fit, although a dominant gene effect could also explain our data. In the AE model, 84% (95% confidence interval 65-94%) of the variance in susceptibility to polymorphic light eruption is attributed to additive genetic factors with the remaining 16% (95% confidence interval 6-35%) to unique environmental effects. These data establish a clear genetic influence in the expression of polymorphic light eruption and provide a basis for examining candidate genes that may be pathogenic in this common condition.