Issues in the epidemiology of melanoma

A meta-analysis of XPC Lys939Gln polymorphism and melanoma susceptibility

BACKGROUND

It has been reported that polymorphisms of XPC Lys939Gln may affect the risk of melanom. However, the results have been inconsistent.We performed a comprehensive meta-analysis to determine the association between XPC Lys939Gln polymorphism and melanoma susceptibility.

METHODS

Based on comprehensive searches of the MEDLINE, EMBASE and ISI Web of knowledge, China National Knowledge Infrastructure (CNKI) and Wanfang Database, we identified eligible studies about the association between XPC Lys939Gln polymorphism and melanoma risk.

RESULTS

A total of 4631 cases and 5111 controls in studies were included in this meta-analysis. All studies were conducted in Caucasian populations. Allele model (Gln vs. Lys: P = 0.22; OR = 1.07, 95% CI = 0.96-1.18), and homozygous model (Gln/Gln vs. Lys/Lys: P = 0.66; OR = 1.03, 95% CI = 0.91-1.17) did not show increased risk of developing melanoma. Similarly, dominant model Gln/Gln and Gln/Lys vs. Lys/Lys: P = 0.07; OR = 1.17, 95% CI = 0.99-1.40) and recessive model (Gln/Gln vs. Gln/Lys and Lys/Lys: P = 0.67; OR = 1.03, 95% CI = 0.90-1.19) failed to show increased risk of developing melanoma.

CONCLUSION

Our pooled data suggest that there was no evidence for a major role of XPC Lys939Gln polymorphism in the pathogenesis of melanoma.

Long-term outcomes and prognostic factors of high-risk malignant melanoma patients after surgery and adjuvant high-dose interferon treatment: a single-center experience

BACKGROUND

Surgical excision constitutes an important part of the treatment of local advanced malignant melanoma. Due to the high recurrence risk, adjuvant high-dose interferon therapy is still the only therapy used in stage IIB and III high-risk melanoma patients.

METHODS

One hundred two high-risk malignant melanoma patients who received high-dose interferon-α-2b therapy were evaluated retrospectively. The clinicopathological features, survival times, and prognostic factors of the patients were determined.

RESULTS

The median disease-free and overall survival times were 25.2 and 60.8 months, respectively. Our findings revealed that male gender, advanced disease stage, lymph node involvement, lymphatic invasion, the presence of ulceration, and a high Clark level were significant negative prognostic factors.

CONCLUSION

In light of the favorable survival results obtained in this study, high-dose interferon treatment as adjuvant therapy for high-risk melanoma is still an efficient treatment and its possible side effects can be prevented by taking the necessary precautions.

UV radiation and the skin

UV radiation (UV) is classified as a "complete carcinogen" because it is both a mutagen and a non-specific damaging agent and has properties of both a tumor initiator and a tumor promoter. In environmental abundance, UV is the most important modifiable risk factor for skin cancer and many other environmentally-influenced skin disorders. However, UV also benefits human health by mediating natural synthesis of vitamin D and endorphins in the skin, therefore UV has complex and mixed effects on human health. Nonetheless, excessive exposure to UV carries profound health risks, including atrophy, pigmentary changes, wrinkling and malignancy. UV is epidemiologically and molecularly linked to the three most common types of skin cancer, basal cell carcinoma, squamous cell carcinoma and malignant melanoma, which together affect more than a million Americans annually. Genetic factors also influence risk of UV-mediated skin disease. Polymorphisms of the melanocortin 1 receptor (MC1R) gene, in particular, correlate with fairness of skin, UV sensitivity, and enhanced cancer risk. We are interested in developing UV-protective approaches based on a detailed understanding of molecular events that occur after UV exposure, focusing particularly on epidermal melanization and the role of the MC1R in genome maintenance.

Effects of photoaging information and UV photo on sun protection intentions and behaviours: a cross-regional comparison

There is limited empirical evidence regarding differences in sun protection practices in different regions of the USA. This study examined whether there are regional differences in the efficacy of exposure to UV photographs and photoaging information (e.g. wrinkles and age spots) for increasing sun protection behaviours. Students attending a public university in either the Midwestern (Iowa) or Southwestern (Southern California) US reported baseline sun exposure and protection practices and were then randomly assigned to either receive information about photoaging, have a UV photo taken, both receive photoaging information and have a UV photo taken, or to receive neither intervention. Sun protection intentions were assessed immediately after the interventions, and both self-reported sun protection behaviours and an objective assessment (via spectrophotometry) of skin colour change were measured at the end of summer and one year following the interventions. The results showed a pervasive pattern of more risky UV exposure and less sun protection use at the Iowa site than at the Southern California site both prior to and following the interventions. Both interventions increased future sun protection intentions regardless of region. However, the intervention effects on skin colour and UV exposure differed across region, with generally more reliable effects at the Iowa site.

Xeroderma pigmentosum genes and melanoma risk

Xeroderma pigmentosum is a rare autosomal recessive disease that is associated with a severe deficiency in nucleotide excision repair. The presence of a distinct the nucleotide excision repair (NER) mutation signature in melanoma suggests that perturbations in this critical repair process are likely to be involved with disease risk. We hypothesized that persons with polymorphic NER gene(s) are likely to have reduced NER activity and are consequently at an increased risk of melanoma development. We assessed the association between 94 SNPs within seven XP genes (XPA-XPG) and the melanoma risk in the Polish population. We genotyped 714 unselected melanoma patients and 1,841 healthy adults to determine if there were any polymorphisms differentially represented in the disease group. We found that a significantly decreased risk of melanoma was associated with the Xeroderma pigmentosum complementation (XPC) rs2228000_CT genotype (odds ratio [OR] = 0.15; p < 0.001) and the rs2228000_TT genotype (OR = 0.11; p < 0.001) compared to the reference genotype. Haplotype analysis within XPC revealed the rs2228001_A + G1475A_G + G2061A_A + rs2228000_T + rs3731062_C haplotype (OR = 0.26; p < 0.05) was associated with a significantly decreased disease risk. The haplotype analysis within the Xeroderma pigmentosum group D (XPD) showed a modest association between two haplotypes and a decrease in melanoma risk. There were no major differences between the prevalence of the XP polymorphisms among young or older patients with melanoma. Linkage disequilibrium of XPC: rs2228001, G1475A, G2061A, rs2228000 and rs3731062 was found. The data from our study support the notion that only XPC and XPD genes are associated with melanoma susceptibility.

A cancer terminator virus eradicates both primary and distant human melanomas

The prognosis and response to conventional therapies of malignant melanoma inversely correlate with disease progression. With increasing thickness, melanomas acquire metastatic potential and become inherently resistant to radiotherapy and chemotherapy. These harsh realities mandate the design of improved therapeutic modalities, especially those targeting metastases. To develop an approach to effectively treat this aggressive disease, we constructed a conditionally replication-competent adenovirus in which expression of the adenoviral E1A gene, necessary for replication, is driven by the cancer-specific promoter of progression-elevated gene-3 (PEG-3) and which simultaneously expresses mda-7/IL-24 in the E3 region of the adenovirus (Ad.PEG-E1A-mda-7), a cancer terminator virus (CTV). This CTV produces large quantities of MDA-7/IL-24 protein as a function of adenovirus replication uniquely in cancer cells. Infection of Ad.PEG-E1A-mda-7 (CTV) in normal human immortal melanocytes and human melanoma cells demonstrates cancer cell-selective adenoviral replication, mda-7/IL-24 expression, growth inhibition and apoptosis induction. Injecting Ad.PEG-E1A-mda-7 CTV into xenografts derived from MeWo human metastatic melanoma cells in athymic nude mice completely eliminated not only primary treated tumors but also distant non-treated tumors (established in the opposite flank), thereby implementing a cure. These provocative findings advocate potential therapeutic applications of this novel virus for treating patients with advanced melanomas with metastases.

Exposure to sunlamps, tanning beds, and melanoma risk

OBJECTIVE

To estimate the separate effects of sunlamp and tanning bed device use on melanoma risk.

METHODS

Population-based case-control study of 423 cases of melanoma and 678 controls in the state of New Hampshire. Exposure data, including sunlamp and tanning bed use, were collected by telephone interview. Associations were evaluated using logistic regression analyses.

RESULTS

About 17% of participants ever used a sunlamp, and most use (89%) occurred before 1980. The OR was 1.39 (95% CI 1.00-1.96) for ever using a sunlamp, 1.23 (95% CI 0.81-1.88) for those starting sunlamp use <20 years, and 1.71 (95% CI 1.00-2.92) for those starting >/=20 years. Data suggested increasing risk with number of sunlamp uses and with duration of use (tests of trend p = 0.02). The overall prevalence of tanning bed use was 22% and most use (83%) occurred after 1980. The OR was 1.14 (95% CI 0.80-1.61) for ever using a tanning bed; there was no evidence that risk increased with frequency or duration of use. The OR was 1.96 (95% CI 1.06-3.61) for having used both devices.

CONCLUSION

Results suggest a modest association between sunlamp use and melanoma risk, and increasing risk with greater frequency and duration of use. No association with tanning bed use was found, but sufficient lag time may not have elapsed to assess a potential effect.

Alkylating benzamides with melanoma cytotoxicity: experimental chemotherapy in a mouse melanoma model

The in-vivo antineoplastic potential of the alkylating N-(2-dialkylaminoethyl)benzamides BZA1 and BZA2, novel melanoma targeted anticancer drugs, was evaluated in a mouse melanoma model with nude mice bearing subcutaneous SkMel28, B16 or WM266-4. The maximal tolerated dose (MTD) for the intraperitoneal application of both agents was found to be 24 mg/kg. Treatment was initiated with an intraperitoneal injection of 8 mg/kg of BZA1 or BZA2 on days 0, 2 and 4 in the case of B16 melanoma on days 0, 1 and 2 after the onset of the experiment, when the mean tumor diameter ranged within 4-6 mm. The experiment was terminated when the mean tumor diameter in the control group had reached a value of 12 mm. Tumor growth delay of these agents was compared with dacarbazine (3x250 mg/kg), chlorambucil (3x5 mg/kg) and an untreated control group. Significant tumor growth delay was observed under BZA1, BZA2 and dacarbazine treatment compared with the untreated control group in all three evaluated melanomas with insignificant differences among BZA1, BZA2 and dacarbazine. The insignificant effect of chlorambucil and the strong improvement on growth delay achieved with BZA1 and BZA2 demonstrated melanoma targeting characteristics of the N-(2-dialkylaminoethyl)benzamide structure element. Dacarbazine was more effective in the in-vivo antineoplastic assay compared with the in-vitro cytotoxicity studies, probably due to hepatic bioactivation. Similar side effect intensity of BZA2 and dacarbazine was observed, whereas BZA1 was more toxic. BZA2 might represent an alternative antimelanoma drug, especially in patients not responding to dacarbazine.

Epidemiología y supervivencia del melanoma cutáneo en España: estudio de 552 casos (1994-2003)

Studies on epidemiology and survival of patients diagnosed of cutaneous melanoma in our country are few. We described epidemiological, clinical, histopathologic and survival characteristics of patients diagnosed of cutaneous melanoma at Hospital Gregorio Marañón of Madrid during ten years (1994-2003). The incidence of melanoma has doubled in the last decade. An important proportion of melanomas continues to be diagnosed in advanced stages (III-IV; 14.5%). The following factors were associated with a poor global survival: Tumor thickness, ulceration, nodular type, masculine gender and age older than 65.

The effects of gp100 and tyrosinase peptide vaccinations on nevi in melanoma patients

BACKGROUND

A new approach to prevent disease recurrence in high-risk melanoma patients involves immunization with gp100 and tyrosinase peptides. This is the first study to examine the effects of such treatments on nevi.

DESIGN

We studied biopsies of 'clinically atypical' nevi from 10 patients before and after peptide vaccination. All had a cutaneous melanoma measuring at least 1.5 mm in depth, satellite metastases, or at least one positive lymph node. We performed immunohistochemical stains for CD3, CD4, CD8, MHC-I, MHC-II, CD1a, HMB-45, MART-1, tyrosinase, bcl-2, p53, and Ki-67 (mib-1).

RESULTS

Immunohistochemistry showed no differences in staining due to vaccination in either the immunologic or melanocytic markers. However, there was a significant increase in both p53 and bcl-2 staining, and a trend toward decreased Ki-67 staining, in the nevi post-treatment.

DISCUSSION

The primary goal of peptide vaccinations with gp100 and tyrosinase is to activate melanoma-specific T cells in order to prevent melanoma recurrence. Nevi were studied in order to assess the effects on benign melanocytes. No significant changes in lymphocytes, langerhans cells, expression of MHC antigens, or melanocytic markers were found. The increase in p53 and bcl-2 raises the possibility that vaccination with melanocytic antigens stimulates a response in benign melanocytes.

Sun exposure and risk of melanoma

BACKGROUND

As skin cancer education programmes directed to children and adolescents continue to expand, an epidemiological basis for these programmes is necessary to target efforts and plan for further evaluation.

AIMS

To summarise the epidemiological evidence on sun exposure during childhood and adolescence and melanoma risk.

METHODS

A literature review was conducted using Medline (1966 to December 2004) to identify articles relating to sun exposure and melanoma. The review was restricted to studies that included sun exposure information on subjects 18 years of age or younger.

RESULTS

Migrant studies generally indicate an increased melanoma risk in individuals who spent childhood in sunny geographical locations, and decreasing melanoma risk with older age at arrival. Individuals who resided in geographical locations close to the equator or close to the coast during childhood and/or adolescence have an increased melanoma risk compared to those who lived at higher latitudes or never lived near the coast. The intermittent exposure hypothesis remains controversial; some studies indicate that children and adolescents who received intermittent sun exposure during vacation, recreation, or occupation are at increased melanoma risk as adults, but more recent studies suggest intermittent exposure to have a protective effect. The majority of sunburn studies suggest a positive association between early age sunburn and subsequent risk of melanoma.

CONCLUSION

Future research efforts should focus on: (1) clarifying the relation between sun exposure and melanoma; (2) conducting prospective studies; (3) assessing sun exposure during different time periods of life using a reliable and quantitative method; (4) obtaining information on protective measures; and (5) examining the interrelations between ability to tan, propensity to burn, skin type, history of sunburns, timing and pattern of sun exposure, number of nevi, and other host factors in the child and adolescent populations.

Familial malignant melanoma - overview

Approximately 3-15% of all malignant melanomas (MM) are familial cases. MM is a highly heterogeneous tumour type from a genetic perspective. Pedigrees with disease confined to a single generation of siblings or MM occurring among second- or third-degree relatives suggest multifactorial polygenic inheritance. However, not infrequently, within large families aggregations of MM are consistent with autosomal dominant inheritance, suggesting a hereditary syndrome caused by germline alterations of a single gene. Several different genes are involved in the development of MM. However, even when taken together they are responsible for less than 20% of all MM cases. It is thus necessary to perform association studies focused on genetic markers that could be used in identifying patients with a high risk of MM. Evaluation of aggregations of MM and other malignancies, like breast cancer, could be essential in identifying relatives of MM probands being at high risk of developing malignancies other than MM. The ultimate goal is to apply in these cases prevention recommendations and surveillance protocols to reduce the disease risk.

Development and reliability of a brief skin cancer risk assessment tool

This study aimed to develop and pilot test a brief skin cancer risk assessment tool (BRAT), a self-administered instrument that can be reliably used to assess skin cancer risk. To develop the BRAT, we critically reviewed published literature on risk factors; formulated a draft questionnaire; pilot tested the questionnaire; and retested 1 month later. The BRAT items address the key risk factors for melanoma and other keratinocyte skin cancers: ethnicity, personal and family history of skin cancer, mole count, freckles, childhood residence, sunburn history, and sun sensitivity factors (skin color, natural hair color, ease of sunburning and tanning). One hundred sixty-five persons completed the initial BRAT pilot study, and 52 additional people at moderate- or high-risk completed a second BRAT pilot study. Results were as follows: using a dichotomous risk measure, about 90% of subjects would be correctly classified at baseline and follow-up. Weighted kappa for the total BRAT score (0.41-0.68) and for individual items (0.57-0.99) were fair to good, as were correlation coefficients. The BRAT has acceptable to good reproducibility. Reliability statistics compared favorably with those reported in the literature for similar measures.

Genetic epidemiology of melanoma

Melanoma incidence has risen in many Caucasians populations over the last 20 years and research on the potential environmental and genetic risk factors has led to some interesting new findings but also to many more questions. The relationship between melanoma and ultraviolet radiation is complex and this area of research is controversial especially regarding the use of sunbeds and sunscreens. In terms of genetic factors, the discovery of two genes CDKN2A and CDK4 has been a great advance with more understanding of melanocyte biology in relation to defects in senescence. For phenotypic risk factors such as fair skin and high numbers of naevi, the role of genetic factors is clearly evident but these traits are complex and the discovery of genes involved in skin pigmentation and naevi formation is not an easy task. Research on the MC1R gene has not only shown the importance of this gene in hair and skin pigmentation but also in senescence and immunity. Functional studies involving CDKN2A and MC1R are leading to important new findings. There is also some hope regarding the use of micro-arrays in helping to dissect many genetic events in melanoma. The collection of large datasets including family, twin and case-control studies as well as tumour banks with collaborations between countries will hopefully lead to more discoveries. For the primary and secondary prevention of this tumour, efforts need to be sustained in public health campaigns on sun exposure and the recognition of individuals at high risk.

Epidemiology of malignant melanoma

Trends in melanoma incidence have shown an increase in thinner, less lethal tumors in recent years. The overall increases in melanoma incidence have begun to slow in Western Europe and North America. Environmental risk factors are important in the development of melanomas in individuals with high-risk phenotypes, and these people should modify their recreational and overall UV exposure. Primary prevention of melanoma and early detection are essential to reduce melanoma mortality in future years. The complex relationships between genetic factors and patterns of sun exposure, especially in childhood, are the focus of continued research.

Why is epiluminescence microscopy important?

The new morphological information provided by epiluminescence microscopy (ELM) requires a fresh approach to the analysis of pigmented lesions. It necessitates a learning process that pertains to the recognition of hitherto unknown morphological features and is based on the discrimination of these features and their combination into two different patterns. ELM has been shown to improve the sensitivity and specificity of the diagnosis of melanoma and other pigmented lesions by 25-30%. Digitized ELM (DELM) provides an unlimited capacity for data storage and retrieval. It is a computerized imaging method, objective and noninvasive; it provides objective evidence of lesional changes on follow-up; documents growth and any changes in the structure and shape of lesions; and thus helps in decisions on whether to excise them or not. It provides for quality control by means of the aforementioned documentation, which may also serve as back-up in the case of medico-legal problems. In addition, the spectrum is widened by the dimension of teledermatology and cybernet computer-assisted diagnosis, which holds great promise for the future. ELM and DELM are thus the most important single development of the past three decades in the early diagnosis of melanoma.

Melanoma incidence trends

This article describes melanoma as an important health concern because of its rapid and continuous growth in many parts of the world. In the United States, a persistent increase in incidence is seen, which has started to slow in recent years. In some countries, differing trends are seen in younger people, with incidence and mortality rates leveling off or decreasing in this population. This article describes that despite this leveling off, melanoma incidence is likely to continue to rise in the near future, because rates are still increasing in older people who comprise most of those afflicted with melanoma.

Locally recurrent malignant melanoma characteristics and outcomes: a single-institution study

Despite improvements in the identification and treatment of melanoma, local recurrence continues to challenge the success of current melanoma therapy. A retrospective analysis of 1,996 patients presenting from 1990 to 1997 at the Pigmented Lesion Group of the University of Pennsylvania was performed to assess clinical characteristics and outcomes of locally recurrent melanoma. The cases were analyzed by chart and pathological slide review. A control group was identified for statistical comparison. The incidence of locally recurrent melanoma during the study period was 2.2%. Lentigo maligna melanoma (LMM) accounted for 37% of the local recurrences. Increased tumor thickness and microsatellites were associated with "early" local recurrence and decreased survival from time of recurrence. Nineteen percent of the local recurrences occurred more than 5 years after the initial definitive treatment. The preponderance of locally recurrent LMM suggests the need for refinements in the techniques of margin identification and surgical excision of LMM. Tumors with increased thickness and microsatellites should receive particularly close attention. Lastly, with nearly 20% of the local recurrences occurring more than 5 years after the initial date of treatment, the authors suggest extending the follow-up time for all melanoma lesions beyond 5 years.

Cutaneous malignancies and their management

Skin cancer is the most common malignancy occurring in humans, and the incidence of basal cell carcinoma, squamous cell carcinoma, and melanoma continues to rise. Advances in the diagnosis and treatment of skin cancer have led to more successful management of these tumors. A number of options for the treatment of skin cancer are available to the patient and physician, allowing for high cure rates and excellent functional and cosmetic outcomes.

The value of tan lines: vulvar melanoma and ultraviolet rays

Recreational sun exposure of the general population has increased. There is less clothing on the beaches, increased accessibility to tropical beaches, and increased use of artificial suntanning equipment. The vulva, traditionally, has been protected from sun exposure. In this age of nude sunbathing, particularly within the confines of a tanning bed, it is interesting to ponder whether such exposure would affect the incidence of melanoma of the vulva.

Pediatric melanoma: confirming the diagnosis with sentinel node biopsy

Many pediatric melanoma lesions present at a more advanced stage than those in the adult population. Clinical and histological melanoma mimics, including a subset of Spitz nevi, are difficult to discriminate from melanoma. When dealing with a childhood melanoma, the clinician is likely to be faced with a thick lesion, and one in which the actual diagnosis may even be in doubt. There is a paucity of data to guide the physician in his management of melanoma in this age group, particularly with respect to node status and adjuvant therapy. The authors present two cases of pediatric melanoma in which the novel use of sentinel node biopsy helped confirm the diagnosis of melanoma, determined the need for full lymph node dissection, and guided the use of adjuvant interferon therapy.

Fine needle aspiration in the diagnosis of metastatic melanoma

BACKGROUND

Fine needle aspiration is an accurate technique to diagnose metastatic melanoma. Few reports exist in the literature describing its usefulness in many patients with melanoma confirmed by open biopsy.

OBJECTIVE

The purpose of this study was to determine the utility and predictive value of fine needle aspiration in patients with malignant melanoma who presented with lesions suspected to be metastatic.

METHODS

We retrospectively reviewed 99 cases of fine needle aspiration and the corresponding histologic findings obtained by open biopsy in 82 patients.

RESULTS

Of the 99 cases, 86 were positive for melanoma, 12 were negative, and one was indeterminate. The positive predictive value of fine needle aspiration was 99%. One patient had a false-positive diagnosis.

CONCLUSION

Fine needle aspiration is a rapid, accurate, and minimally invasive procedure that is useful in the diagnosis of metastatic melanoma. Patients with a positive aspirate of palpable regional nodes can proceed directly to surgery, bypassing the need for an open biopsy.

Sunscreen

Skin cancer prevention is increasingly a focus of public health campaigns. The most important avoidable cause of skin cancer is ultraviolet radiation from the sun, but sunscreens are often used in a suboptimal manner, compromising their effectiveness. People may "compensate" for the use of sunscreen by increasing their time in the sun, which can have adverse effects on health. Epidemiologic studies of sunscreen use have suffered from important methodologic limitations. A clearer picture of the impact of sunscreens is emerging from randomized trials that have recently been published or presented. The available evidence supports the current recommendation to "Slip! Slop! Slap!" when in the sun.