Involvement of ANXA5 and ILKAP in susceptibility to malignant melanoma

Single nucleotide-polymorphisms (SNPs) are a source of diversity among human population, which may be responsible for the different individual susceptibility to diseases and/or response to drugs, among other phenotypic traits. Several low penetrance susceptibility genes associated with malignant melanoma (MM) have been described, including genes related to pigmentation, DNA damage repair and oxidative stress pathways. In the present work, we conducted a candidate gene association study based on proteins and genes whose expression we had detected altered in melanoma cell lines as compared to normal melanocytes. The result was the selection of 88 loci and 384 SNPs, of which 314 fulfilled our quality criteria for a case-control association study. The SNP rs6854854 in ANXA5 was statistically significant after conservative Bonferroni correction when 464 melanoma patients and 400 controls were analyzed in a discovery Phase I. However, this finding could not be replicated in the validation phase, perhaps because the minor allele frequency of SNP rs6854854 varies depending on the geographical region considered. Additionally, a second SNP (rs6431588) located on ILKAP was found to be associated with melanoma after considering a combined set of 1,883 MM cases and 1,358 disease-free controls. The OR was 1.29 (95% CI 1.12–1.48; p-value = 4×10⁻⁴). Both SNPs, rs6854854 in ANXA5 and rs6431588 in ILKAP, show population structure, which, assuming that the Spanish population is not significantly structured, suggests a role of these loci on a specific genetic adaptation to different environmental conditions. Furthermore, the biological relevance of these genes in MM is supported by in vitro experiments, which show a decrease in the transcription levels of ANXA5 and ILKAP in melanoma cells compared to normal melanocytes.

Inherited variation in the PARP1 gene and survival from melanoma

We report the association of an inherited variant located upstream of the poly(adenosine diphosphate-ribose) polymerase 1 (PARP1) gene (rs2249844), with survival in 11 BioGenoMEL melanoma cohorts. The gene encodes a protein involved in a number of cellular processes including single-strand DNA repair. Survival analysis was conducted for each cohort using proportional hazards regression adjusting for factors known to be associated with survival. Survival was measured as overall survival (OS) and, where available, melanoma-specific survival (MSS). Results were combined using random effects meta-analysis. Evidence for a role of the PARP1 protein in melanoma ulceration and survival was investigated by testing gene expression levels taken from formalin-fixed paraffin-embedded tumors. A significant association was seen for inheritance of the rarer variant of PARP1, rs2249844 with OS (hazard ratio (HR) = 1.16 per allele, 95% confidence interval (CI) 1.04–1.28, p = 0.005, eleven cohorts) and MSS (HR = 1.20 per allele, 95% CI 1.01–1.39, p = 0.03, eight cohorts). We report bioinformatic data supportive of a functional effect for rs2249844. Higher levels of PARP1 gene expression in tumors were shown to be associated with tumor ulceration and poorer OS.

An inherited variant in the gene coding for vitamin D-binding protein and survival from cutaneous melanoma: a BioGenoMEL study

An association between low serum vitamin D levels and poorer melanoma survival has been reported. We have studied inheritance of a polymorphism of the GC gene, rs2282679, coding for the vitamin D-binding protein, which is associated with lower serum levels of vitamin D, in a meta-analysis of 3137 melanoma patients. The aim was to investigate evidence for a causal relationship between vitamin D and outcome (Mendelian randomization). The variant was not associated with reduced overall survival (OS) in the UK cohort, per-allele hazard ratio (HR) for death 1.23 (95% confidence interval (CI) 0.93, 1.64). In the smaller cohorts, HR in OS analysis was 1.07 (95% CI 0.88, 1.3) and for all cohorts combined, HR for OS was 1.09 (95% CI 0.93, 1.29). There was evidence of increased melanoma-specific deaths in the seven cohorts for which these data were available. The lack of unequivocal findings despite the large sample size illustrates the difficulties of implementing Mendelian randomization.

Telomerase reverse transcriptase promoter mutations in primary cutaneous melanoma

We previously reported a disease segregating causal germline mutation in a melanoma family and recurrent somatic mutations in metastasized tumours from unrelated patients in the core promoter region of the telomerase reverse transcriptase (TERT) gene. Here we show that the TERT promoter mutations, besides causing an increased gene expression, associate with increased patient age, increased Breslow thickness and tumour ulceration in 287 primary melanomas. The mutations are more frequent at both intermittently and chronically sun-exposed sites than non-exposed sites and tend to co-occur with BRAF and CDKN2A alterations. The association with parameters generally connected with poor outcome, coupled with high recurrence and mechanistic relevance, raises the possibility of the eventual use of TERT promoter mutations in the disease management.

Paraneoplastic dermatomyositis: a study of 12 cases

INTRODUCTION AND OBJECTIVES

Adult dermatomyositis presents as a paraneoplastic syndrome in up to 25% of cases, but no clinical, histologic, or laboratory markers completely specific for paraneoplastic disease in dermatomyositis have been identified to date. Furthermore, studies on adult dermatomyositis do not usually report the frequency of cutaneous features of dermatomyositis in patients with associated cancer. Our aim was to review the characteristics of paraneoplastic dermatomyositis in patients seen at our hospital.

MATERIAL AND METHODS

We studied 12 cases of paraneoplastic dermatomyositis and recorded patient age and sex, associated cancer, time between onset of dermatomyositis and cancer, emergent cutaneous manifestations, muscle involvement, dysphagia, lung disease, and levels of creatine phosphokinase and circulating autoantibodies.

RESULTS

The mean age of the patients was 61 years and the 2 most common malignancies were ovarian cancer and bladder cancer. The mean time between the diagnosis of cancer and dermatomyositis was 7 months and in most cases, the cancer was diagnosed first. Seven patients had amyopathic dermatomyositis. The most common cutaneous signs were a violaceous photodistributed rash sparing the interscapular area and a heliotrope rash, followed by Gottron papules and cuticle involvement. Superficial cutaneous necrosis was observed in 3 cases. Myositis-specific autoantibodies were not detected in any of the 6 patients who underwent this test.

CONCLUSIONS

Paraneoplastic dermatomyositis is often amyopathic. There are no specific cutaneous markers for malignancy in dermatomyositis. Myositis-specific antibodies are not associated with paraneoplastic dermatomyositis.

Germline sequence variants in TGM3 and RGS22 confer risk of basal cell carcinoma

To search for new sequence variants that confer risk of cutaneous basal cell carcinoma (BCC), we conducted a genome-wide association study of 38.5 million single nucleotide polymorphisms (SNPs) and small indels identified through whole-genome sequencing of 2230 Icelanders. We imputed genotypes for 4208 BCC patients and 109 408 controls using Illumina SNP chip typing data, carried out association tests and replicated the findings in independent population samples. We found new BCC susceptibility loci at TGM3 (rs214782[G], P = 5.5 × 10⁻¹⁷, OR = 1.29) and RGS22 (rs7006527[C], P = 8.7 × 10⁻¹³, OR = 0.77). TGM3 encodes transglutaminase type 3, which plays a key role in production of the cornified envelope during epidermal differentiation.

Prognostic value of BRAF mutations in localized cutaneous melanoma

BACKGROUND

BRAF mutations are frequent in melanoma but their prognostic significance remains unclear.

OBJECTIVE

We sought to further evaluate the prognostic value of BRAF mutations in localized cutaneous melanoma.

METHODS

We undertook an observational retrospective study of 147 patients with localized invasive (stages I and II) cutaneous melanomas to determine the prognostic value of BRAF mutation status.

RESULTS

After a median follow-up of 48 months, patients with localized melanomas with BRAF-mutant melanomas exhibited poorer disease-free survival than those with BRAF-wt genotype (hazard ratio 2.2, 95% confidence interval 1.1-4.3) even after adjustment for Breslow thickness, tumor ulceration, location, age, sex, and tumor mitotic rate.

LIMITATIONS

The retrospective design and the small number of events are limitations.

CONCLUSIONS

Our findings suggest that reappraisal of clinical treatment approaches for patients with localized melanoma harboring tumors with BRAF mutation might be warranted.

Melanoma characteristics at diagnosis from the Spanish National Cutaneous Melanoma Registry: 15 years of experience

BACKGROUND AND OBJECTIVES

The Spanish National Cutaneous Melanoma Registry (Registro Nacional de Melanoma Cutáneo [RNMC]) was created in 1997 to record the characteristics of melanoma at diagnosis. In this article, we describe the characteristics of these tumors at diagnosis.

PATIENTS AND METHODS

This was a cross-sectional observational study of prevalent and incident cases of melanoma for which initial biopsy results were available in the population-based RNMC.

RESULTS

The RNMC contains information on 14,039 patients. We analyzed the characteristics of 13,628 melanomas diagnosed between 1997 and 2011. In total, 56.5% of the patients studied were women and 43.5% were men. The mean age of the group was 57 years (95% CI, 56.4-57 years) while median age was 58 years. The most common tumor site was the trunk (37.1%), followed by the lower limbs (27.3%). The most frequent clinical-pathologic subtype was superficial spreading melanoma (n=7481, 62.6%), followed by nodular melanoma (n=2014, 16.8%). Localized disease was observed in 86.2% of cases (n=10,382), regional metastasis in 9.9% (n=1188), and distant metastasis in 3.9% (n=479). Independently of age at diagnosis, men had thicker tumors, more ulceration, higher lactate dehydrogenase levels, and a higher rate of metastasis than women (P<.001).

CONCLUSIONS

Based on our findings, melanoma prevention campaigns should primarily target men over 50 years old because they tend to develop thicker tumors and therefore have a worse prognosis.

Distribution of MC1R variants among melanoma subtypes: p.R163Q is associated with lentigo maligna melanoma in a Mediterranean population

BACKGROUND

Cutaneous melanoma tumour is classified into clinicohistopathological subtypes that may be associated with different genetic and host factors. Variation in the MC1R gene is one of the main factors of risk variation in sporadic melanoma. The relationship between MC1R variants and the risk of developing a specific subtype of melanoma has not been previously explored.

OBJECTIVES

To analyse whether certain MC1R variants are associated with particular melanoma subtypes with specific clinicohistopathological features.

METHODS

An association study was performed between MC1R gene variants and clinicopathological subtypes of primary melanoma derived from 1679 patients.

RESULTS

We detected 53 MC1R variants (11 synonymous and 42 nonsynonymous). Recurrent nonsynonymous variants were p.V60L (30·0%), p.V92M (11·7%), p.D294H (9·4%), p.R151C (8·8%), p.R160W (6·2%), p.R163Q (4·2%) p.R142H (3·3%), p.I155T (3·8%), p.V122M (1·5%) and p.D84E (1·0%). Melanoma subtypes showed differences in the total number of MC1R variants (P = 0·028) and the number of red hair colour variants (P = 0·035). Furthermore, an association between p.R163Q and lentigo maligna melanoma was detected under a dominant model of heritance (odds ratio 2·16, 95% confidence interval 1·07-4·37; P = 0·044). No association was found between p.R163Q and Fitzpatrick skin phototype, eye colour or skin colour, indicating that the association was independent of the role of MC1R in pigmentation. No association was observed between MC1R polymorphisms and other melanoma subtypes.

CONCLUSIONS

Our findings suggest that certain MC1R variants could increase melanoma risk due to their impact on pathways other than pigmentation, and may therefore be linked to specific melanoma subtypes.

High immunohistochemical nestin expression is associated with greater depth of infiltration in dermatofibrosarcoma protuberans: a study of 71 cases

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) was recently shown to express nestin, a marker that has been associated with poorer prognosis when present in high levels in certain tumors. The objective of this study is to explore the association between high nestin expression and deep invasion.

METHODS

We performed a retrospective, observational study in which we evaluated the degree of nestin expression in 71 DFSP. The odds of fascial involvement was calculated before and after adjusting for the following confounders: age, sex, tumor size, time to diagnosis, tumor site, the presence of fibrosarcomatous areas, pleomorphism, number of mitotic figures and predominant histopathologic pattern. We also calculated the Spearman Rho correlation coefficient between nestin staining intensity and depth of invasion.

RESULTS

Nestin immunopositivity was found in 98.6% of the tumors, and high expression levels were significantly associated with invasion of the fascia. The odds of fascial involvement in tumors with strong nestin staining was 6.56 (p = 0.001) before adjustment for confounders and 14.86 after adjustment (p = 0.007). The Spearman rho correlation coefficient between nestin expression and deep invasion was 0.287 (p = 0.015).

CONCLUSION

High inmunohistochemical nestin expression appears to be associated with deeper invasion in DFSP.

Positive margins in excised dermatofibrosarcoma protuberans: a study of 58 cases treated with slow-Mohs surgery

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is characterized by unpredictable subclinical extension, meaning that positive margins are frequently detected following conventional surgical excision.

OBJECTIVE

To study the presence or absence of residual tumour in DFSP with positive margins after conventional surgery and identify possible predictors of residual tumour or clear margins following a single Mohs micrographic surgery (MMS) stage.

METHODS

A retrospective study of patients with DFSP and positive margins following conventional excision referred for MMS was performed. We studied gender, age, tumour site, time from presentation to diagnosis, and affected margins.

RESULTS

We studied 58 cases, 35 (60.3%) of which had histological evidence of residual tumour. Tumours of the head and neck were significantly associated with the persistence of tumour. A single MMS stage was sufficient to achieve clearance in the majority of cases (n = 46). All tumours with lateral involvement only were resolved with a single Mohs stage.

CONCLUSIONS

DFSPs with positive margins after conventional surgical excision should undergo re-excision because the majority have histologic evidence of residual tumour. Re-excision with 1-cm margins beyond the scar could be an option in certain tumour sites, particularly when it is known which margins are involved.

Variants at the 9p21 locus and melanoma risk

Background

The influence of variants at the 9p21 locus on melanoma risk has been reported through investigation of CDKN2A variants through candidate gene approach as well as by genome wide association studies (GWAS).

Methods

In the present study we genotyped, 25 SNPs that tag 273 variants on chromosome 9p21 in 837 melanoma cases and 1154 controls from Spain. Ten SNPs were selected based on previous associations, reported in GWAS, with either melanocytic nevi or melanoma risk or both. The other 15 SNPs were selected to fine map the CDKN2A gene region.

Results

All the 10 variants selected from the GWAS showed statistically significant association with melanoma risk. Statistically significant association with melanoma risk was also observed for the carriers of the variant T-allele of rs3088440 (540 C>T) at the 3’ UTR of CDKN2A gene with an OR 1.52 (95% CI 1.14-2.04). Interaction analysis between risk associated polymorphisms and previously genotyped MC1R variants, in the present study, did not show any statistically significant association. Statistical significant association was observed for the interaction between phototypes and the rs10811629 (located in intron 5 of MTAP). The strongest association was observed between the homozygous carrier of the A–allele and phototype II with an OR of 15.93 (95% CI 5.34-47.54).

Conclusions

Our data confirmed the association of different variants at chromosome 9p21 with melanoma risk and we also found an association of a variant with skin phototypes.

NRAS and BRAF mutations in cutaneous melanoma and the association with MC1R genotype: findings from Spanish and Austrian populations

There is increasing epidemiologic and molecular evidence that cutaneous melanomas arise through multiple causal pathways. To further define the pathways to melanoma, we explored the relationship between germline and somatic mutations in a series of melanomas collected from 134 Spanish and 241 Austrian patients. Tumor samples were analyzed for melanocortin-1 receptor (MC1R) variants and mutations in the BRAF and NRAS genes. Detailed clinical data were systematically collected from patients. We found that NRAS-mutant melanomas were significantly more likely from older patients and BRAF-mutant melanomas were more frequent in melanomas from the trunk. We observed a nonsignificant association between germline MC1R status and somatic BRAF mutations in melanomas from trunk sites (odds ratio (OR) 1.8 (0.8-4.1), P=0.1), whereas we observed a significant inverse association between MC1R and BRAF for melanomas of the head and neck (OR 0.3 (0.1-0.8), P=0.02). This trend was observed in both the Spanish and Austrian populations.

Clinical presentation of acral lentiginous melanoma: a descriptive study

BACKGROUND AND OBJECTIVE

Acral lentiginous melanomas -the melanomas most commonly found on the distal portions of the limbs- have usually reached more advanced stages than other types of melanoma when diagnosed. Our aim was to describe the clinical presentation of these tumors.

MATERIALS AND METHODS

Retrospective, descriptive, observational study of cases recorded in the database of the Instituto Valenciano de Oncología. In telephone interviews the patients answered a questionnaire on the presenting features of the lesion, on the presence of signs and symptoms included in the Glasgow 7-point checklist and the ABCDEs of melanoma, and on diagnostic delay attributable to patient or physician.

RESULTS

In the interviews with the 23 patients who responded to the questionnaire, we detected a diagnostic delay of more than 1 year attributable to the patient (delay in seeking care) in 30.4% of the cases. Diagnostic delay of more than 1 year attributable to the physician (failure to suspect the diagnosis) was identified in 20%. The most frequent reasons for consulting a physician about a lesion were changes in size, changes in color, bleeding, or failure to heal. In 20% of the cases the evaluating physician did not order histology for over a year.

CONCLUSIONS

Diagnostic delay is a significant problem in acral lentiginous melanoma and may be attributable either to patients or to physicians' failure to recognize warning signs. Melanoma prevention campaigns should place more emphasis on the possibility of melanomas appearing on the palms and, particularly, on the soles.

rs12512631 on the group specific complement (vitamin D-binding protein GC) implicated in melanoma susceptibility

BACKGROUND

Solar radiation should be avoided in melanoma patients. Nevertheless, this is the main means by which the body produces vitamin D. Evidence suggests a protective role against cancer for vitamin D. Since vitamin D performs its function by binding the receptor encoded by the vitamin D-receptor gene (VDR), most studies have focused on polymorphisms (SNPs) within this gene. However, the gene encoding the vitamin D-binding protein (GC) appears in recent studies as a major player in the role of a serum vitamin D level regulator and in Cutaneous Melanoma (CM) predisposition.

METHODS

We performed a case-control study of 12 polymorphisms on GC and 9 on VDR among 530 cases and 314 controls from Spanish population.

RESULTS

We found association between SNP rs12512631, located 3'downstream of GC, and risk of CM that seems to fit a dominant model (OR 1.63 95%CI 1.23-2.17 p-value 7×10(-4)). This association remained Bonferroni's correction and after adjustment for potential confounders (p-value 3×10(-3)) and even after increasing the sample size to 1729 individuals (p-value 0.0129). Moreover, we confirmed evidence of an association between CM susceptibility and the linkage disequilibrium block marked by tag-SNP rs222016 (p-value 0.032). This block covers the GC intron 1 region, with probable regulatory functions.

CONCLUSION

To our knowledge, this is the first vitamin D pathway-related polymorphism study in melanoma risk conducted in the Spanish population. Furthermore, we show an association between polymorphisms in GC and melanoma risk, confirming recent studies in different populations.

Improving sun-safe knowledge, attitude and behaviour in parents of primary school children: a pilot study

Excessive sun exposure, mainly in childhood, represents one of the major skin cancer risk factors. Sun protection habits should start early in life to be effective. The purpose of this study was to investigate knowledge, attitude and sun protection behaviour in parents (P) and in their children (C). The educational intervention addressed the parents of 131 primary school pupils in Valencia, Spain, during the school year 2007-2008. A self-administered pre- and post-intervention questionnaire was handed in during school hours to be filled in by parents. Parents' compliance was very high (88 %). At baseline, regular high-sun-protective-factor (>15) sunscreen use was common (P, 64 %; C, 95 %); wearing clothing (T-shirt: P, 34 %, C, 62 %; hat: P, 29 %, C, 64 %) and sun avoidance at midday (P, 23 %; C, 29 %) were less frequent. Almost 70 % of parents reported difficulties, mainly due to the children's refusal. A high knowledge score (median, 6/7) and a medium/high attitude score (median, 24/30) in parents were observed; however, lifetime sunburn history was generally reported (P, 88 %; C, 24 %). Factors associated with parents' knowledge were a personal history of sunburns and regularly repeating sunscreen application to children (median score: 6 vs 5; p ≤ 0.01) Predictors of a more favourable attitude were female caretakers and having daughters (median score: 30 vs 25 and 25 vs 24, respectively; p ≤ 0.01). A trend towards limited post-intervention positive changes emerged; however, sun avoidance habit decreased (35 vs 20 %, p = 0.01). Despite a high level of parents' knowledge, sun protection in children is not adequate, and sunburns are not uncommon. Unfavourable beliefs and attitudes need to be overcome and quality of messages improved to achieve sun-safe exposure in children.

TERT promoter mutations in familial and sporadic melanoma

Cutaneous melanoma occurs in both familial and sporadic forms. We investigated a melanoma-prone family through linkage analysis and high-throughput sequencing and identified a disease-segregating germline mutation in the promoter of the telomerase reverse transcriptase (TERT) gene, which encodes the catalytic subunit of telomerase. The mutation creates a new binding motif for Ets transcription factors and ternary complex factors (TCFs) near the transcription start and, in reporter gene assays, caused up to twofold increase in transcription. We then screened the TERT promoter in sporadic melanoma and observed recurrent ultraviolet signature somatic mutations in 125 of 168 (74%) of human cell lines derived from metastatic melanomas, 45 of 53 corresponding metastatic tumor tissues (85%), and 25 of 77 (33%) primary melanomas. The majority of those mutations occurred at two positions in the TERT promoter and also generated binding motifs for Ets/TCF transcription factors.

Non-steroidal anti-inflammatory drugs and melanoma

Inflammation is an important contributor to the development and progression of all human cancers. Inflammatory lipid metabolites, prostaglandins, formed from arachidonic acid by prostaglandin H synthases commonly called cyclooxygenases (COXs), bind to specific receptors that activate signaling pathways driving to the development and progression of tumors. Inhibitors of prostaglandin formation, COX inhibitors, including non-steroidal anti-inflammatory drugs (NSAIDs), are well documented agents that inhibit tumor growth and prevent tumor development specially due to long-term use. NSAIDs also alter gene expression independently of COX inhibition which also appear to contribute to the anti-tumorigenic activity of these drugs. In a dermatologic point of view, most investigations are oriented to improve the current knowledge related to the pathogenesis of malignant melanoma, a prevalent skin cancer characterized by a rapid progression with frequent metastases and a poor response to the different available treatments. In the present issue we review the role of inflammation in cutaneous malignant melanoma and its impact on cancer pathogenesis. This topic represents an exciting new area of research, and could potentially result in new targets for melanoma therapy in the future.

Influence of genetic variants in type I interferon genes on melanoma survival and therapy

Melanoma is an immunogenic tumor; however, the efficacy of immune-therapy shows large inter-individual variation with possible influence of background genetic variation. In this study we report the influence of genetic polymorphisms in the type I interferon gene cluster on chromosome 9p22 on melanoma survival. We genotyped 625 melanoma patients recruited in an oncology center in Germany for 44 polymorphisms located on chromosome 9p22 that were informative for 299 polymorphisms and spanned 15 type I interferon genes. Our results showed associations between time to metastasis/survival and two linked (r² = 0.76) polymorphisms, rs10964859 (C>G) and rs10964862 (C>A). The rs10964859 polymorphism was located at 3′UTR and rs10964862 was 9.40 Kb towards 5′UTR of IFNW1 gene. The carriers of the variant alleles of the rs10964859 and rs10964862 polymorphisms were associated with a reduced disease-free survival. The validation of data in an independent group of 710 patients from Spain showed that the direction of the effect was similar. Stratification based on therapy showed that the adverse effect on metastasis development was statistically significant in the patients from Spain who did not receive any treatment and were homozygous for variant allele of rs10964862 (HR = 2.52, 95% CI 1.07–5.90; P = 0.03). Patients homozygous for rs10964859 (HR = 2.01, 95% CI 1.17–3.44; P = 0.01) and rs10964862 (HR 1.84, 95%CI 1.03–3.27, P = 0.04) were associated to increased risk of death following metastasis. GTCGACAA haplotype, found in 8.8% of the patients, was associated with an increased risk of death (HR 1.94, 95%CI 1.16–3.26, P = 0.01). In conclusion, our results identified genetic variants in interferon genes that influence melanoma progression and survival with modulation of effect due to treatment status.

Melanocortin-1 receptor, skin cancer and phenotypic characteristics (M-SKIP) project: study design and methods for pooling results of genetic epidemiological studies

Background

For complex diseases like cancer, pooled-analysis of individual data represents a powerful tool to investigate the joint contribution of genetic, phenotypic and environmental factors to the development of a disease. Pooled-analysis of epidemiological studies has many advantages over meta-analysis, and preliminary results may be obtained faster and with lower costs than with prospective consortia.

Design and methods

Based on our experience with the study design of the Melanocortin-1 receptor (MC1R) gene, SKin cancer and Phenotypic characteristics (M-SKIP) project, we describe the most important steps in planning and conducting a pooled-analysis of genetic epidemiological studies. We then present the statistical analysis plan that we are going to apply, giving particular attention to methods of analysis recently proposed to account for between-study heterogeneity and to explore the joint contribution of genetic, phenotypic and environmental factors in the development of a disease. Within the M-SKIP project, data on 10,959 skin cancer cases and 14,785 controls from 31 international investigators were checked for quality and recoded for standardization. We first proposed to fit the aggregated data with random-effects logistic regression models. However, for the M-SKIP project, a two-stage analysis will be preferred to overcome the problem regarding the availability of different study covariates. The joint contribution of MC1R variants and phenotypic characteristics to skin cancer development will be studied via logic regression modeling.

Discussion

Methodological guidelines to correctly design and conduct pooled-analyses are needed to facilitate application of such methods, thus providing a better summary of the actual findings on specific fields.

Biosynthetic Porcine Collagen Dressings as an Adjunct or Definitive Tool for the Closure of Scalp Defects Without Periosteum

BACKGROUND: Aggressive carcinomas of the scalp usually occur in elderly patients with multiple comorbidities. Complete excision of this type of tumor often involves the removal of periosteum, and the resulting defects can be difficult to reconstruct. OBJECTIVE: To evaluate the usefulness of porcine type I collagen dressings as adjunct or definitive treatment in the surgical closure of scalp defects without periosteum. MATERIALS AND METHODS: We performed a prospective study between January 2009 and November 2011 of patients with scalp defects larger than 5cm resulting from surgery that required the removal of periosteum to obtain tumor-free margins. RESULTS: The most prevalent type of tumor was recurrent cutaneous squamous cell carcinoma. The surgical defects ranged in diameter from 5 to 7cm. In 100% of the patients who received a graft after dressing removal (n=4), the graft took well. In the patients in whom the biosynthetic dressing was definitive (n=6), granulation tissue filled the defect and complete closure was achieved in approximately 3.5 months. CONCLUSIONS: The use of porcine type I collagen dressings as an adjunct or definitive tool for the closure of surgical defects on the scalp measuring more than 5cm in which periosteum has been removed proved to be simple, inexpensive, and effective.

Variants at chromosome 20 (ASIP locus) and melanoma risk

Agouti signaling protein (ASIP) locus on chromosome 20q11 is implicated, as shown by genome-wide association studies, in phenotype variation and melanoma risk. We genotyped 837 melanoma cases and 1,154 controls for 21 single nucleotide polymorphisms (SNPs) informative for 495 polymorphisms at the locus. Our data showed an increased risk of melanoma (odds ratio [OR] 1.27, 95% confidence interval [95% CI] 1.03-1.57) in carriers of the rs4911414 variant, located 120 kb upstream of ASIP. The main effect of rs4911414, as reported previously, was in tandem with a 10 kb adjacent polymorphism rs1015362; two constituted risk-associated haplotype/diplotype. Except for rs1015363, none of the 12 tagging SNPs, genotyped to cover 239.9 kb region with polymorphisms linked to rs4911414 and rs1015362, were associated with melanoma. Our data confirmed a previous association of melanoma risk (OR 1.82, 95% CI 1.37-2.41) with rs4911442, located in intron 5 of the nuclear receptor coactivator 6 (NCOA6) gene. The rs910871, one of the six variants, genotyped to cover NCOA6, showed an association with melanoma risk (OR 1.33, 95% CI 1.04-1.70). Both, rs4911442 and rs910871 were in moderate linkage with a, previously reported, risk-associated rs910873 polymorphism. A haplotype from the variants within NCOA6 showed an association with risk of melanoma (OR 1.49, 95% CI 1.17-1.88). Interaction between risk-associated polymorphisms and previously genotyped melanocortin receptor 1 (MC1R) variants, in our study, was not statistically significant. Nevertheless, the carriers of the variant alleles over the background of MC1R variants were at a higher risk than the carriers not enriched for MC1R variants. Our data confirmed the association of different variants at chromosome 20q11 with melanoma risk.

Inherited variants in the MC1R gene and survival from cutaneous melanoma: a BioGenoMEL study

Inherited MC1R variants modulate MITF transcription factor signaling, which in turn affects tumor cell proliferation, apoptosis, and DNA repair. The aim of this BioGenoMEL collaborative study in 10 melanoma cohorts was to test the hypothesis that inherited variants thereby moderate survival expectation. A survival analysis in the largest cohort (Leeds) was carried out adjusting for factors known to impact on survival. The results were then compared with data from nine smaller cohorts. The absence of any consensus MC1R alleles was associated with a significantly lower risk of death in the Leeds set (HR, 0.64; 95% CI, 0.46–0.89) and overall in the 10 data sets (HR, 0.78; 95% CI, 0.65–0.94) with some support from the nine smaller data sets considered together (HR, 0.83; 95% CI, 0.67–1.04). The data are suggestive of a survival benefit for inherited MC1R variants in melanoma patients.

A randomized pilot comparative study of topical methyl aminolevulinate photodynamic therapy versus imiquimod 5% versus sequential application of both therapies in immunocompetent patients with actinic keratosis: clinical and histologic outcomes

BACKGROUND

Photodynamic therapy (PDT) and imiquimod are the treatments of choice for actinic keratosis (AK). As they have different mechanisms of action, it seems reasonable to assume that applying both treatments sequentially would be efficacious.

OBJECTIVES

We sought to determine which of these therapeutic modalities provides a better clinical and histologic response in patients with AK and whether sequential use of both was more efficacious than each separately.

METHODS

Patients were randomly assigned to one treatment group: group 1, PDT only; group 2, imiquimod only; or group 3, sequential use of PDT and imiquimod. The primary outcome measure was complete clinical response. Partial clinical response was defined as a reduction of more than 75% in the initial number of lesions. A complete clinicopathologic response was defined as lack of evidence of AK in the biopsy specimen.

RESULTS

In all, 105 patients completed the study (group 1, 40 patients; group 2, 33 patients; group 3, 32 patients). Sequential application of PDT and imiquimod was more efficacious in all the outcome measures. More patients were satisfied with PDT than with the other two modalities (P = .003). No significant differences were observed among the 3 modalities and tolerance to treatment.

LIMITATIONS

Only one cycle of imiquimod was administered. The follow-up period was brief.

CONCLUSIONS

Sequential application of PDT and imiquimod provides a significantly better clinical and histologic response in the treatment of AK than PDT or imiquimod monotherapy. It also produces less intense local reactions and better tolerance and satisfaction than imiquimod monotherapy.

Chronology of metastasis in cutaneous melanoma: growth rate model

In humans, it is not possible to obtain experimental evidence of when a cancer begins to metastasize. The purpose of this study was to estimate the time of onset of metastatic dissemination in cutaneous melanoma using a model based on its growth rate (GR). The critical time of onset of metastatic dissemination below which no cases of fatal melanomas were seen may be described with a potential function in which this time is inversely proportional to the GR. The critical time of development beyond which a melanoma may metastasize presents great variation. This time was just 1 month for those melanomas with a fast GR, whereas it was over 5 years for those with a very slow GR. Quantitatively, the fastest-growing melanomas began metastasizing with a greater thickness than the slowest-growing melanomas. A correlation exists between the critical time of onset of metastatic potential and the GR of the melanoma. These results may well have relevance to the understanding of mechanisms of tumor dissemination and for the design of future studies on melanomas, irrespective of whether they are basic studies on biomolecular mechamisms or clinical studies.