Case-control study to identify melanoma risk factors in the Belgian population: the significance of clinical examination

MelaNostrum: a consensus questionnaire of standardized epidemiologic and clinical variables for melanoma risk assessment by the melanostrum consortium

BACKGROUND

Many melanoma observational studies have been carried out across different countries and geographic areas using heterogeneous assessments of epidemiologic risk factors and clinical variables.

AIM

To develop a consensus questionnaire to standardize epidemiologic and clinical data collection for melanoma risk assessment.

METHODS

We used a stepwise strategy that included: compilation of variables from case-control datasets collected at various centres of the MelaNostrum Consortium; integration of variables from published case-control studies; consensus discussion of the collected items by MelaNostrum members; revision by independent experts; addition of online tools and image-based charts; questionnaire testing across centres and generation of a final draft.

RESULTS

We developed a core consensus questionnaire (MelanoQ) that includes four separate sections: A. general and demographic data; B. phenotypic and ultraviolet radiation exposure risk factors and lifestyle habits; C. clinical examination, medical and family history; and D. diagnostic data on melanoma (cases only). Accompanying online tools, informative tables, and image-based charts aid standardization. Different subsections of the questionnaire are designed for self-administration, patient interviews performed by a physician or study nurse, and data collection from medical records.

CONCLUSIONS

The MelanoQ questionnaire is a useful tool for the collection and standardization of epidemiologic and clinical data across different studies, centres, cultures and languages. This will expedite ongoing efforts to compile high-quality data for pooled analyses or meta-analyses and offer a solid base for the design of clinical, epidemiologic and translational studies on melanoma.

Current Data on Risk Factor Estimates Does Not Explain the Difference in Rates of Melanoma between Hispanics and Non-Hispanic Whites

United States Hispanics have seven times lower melanoma incidence rates than non-Hispanic whites (NHW). It is unclear whether this difference can be explained solely by phenotypic risk factors, like darker skin, or whether modifiable risk factors, like sun exposure, also play a role. The purpose of this paper is to summarize what is currently known about melanoma risk factors among Hispanics and NHWs, and whether or not those differences could explain the difference in melanoma incidence. Through literature review, relative risks and prevalence of melanoma risk factors in Hispanics and NHWs were identified and used to calculate the expected rate in Hispanics and rate ratio compared to NHWs. We found that melanoma risk factors either have similar frequency in Hispanics and NHWs (e.g., many large nevi) or are less frequent in Hispanics but do not explain a high proportion of disease variation (e.g., red hair). Considering current knowledge of risk factor prevalence, we found that melanoma incidence rates in the two groups should actually be similar. Sun exposure behavior among Hispanics may contribute to the explanation for the 7-fold difference in melanoma rates. Currently, limited data exist on sun exposure behavior among Hispanics, but possibilities for improving primary prevention by further studying these practices are substantial.

Nevus-associated melanomas: clinicopathologic features

OBJECTIVES

The clinical significance of nevus-associated melanoma compared with de novo melanomas remains controversial. It has been suggested that nevus-associated melanomas have a higher Breslow thickness and therefore worse prognosis. Over a 10-year period, this study evaluated the incidence of nevus-associated melanoma and its prognostic significance related to clinicopathologic features.

METHODS

Cross-sectional study from 1995 through 2004 in a dermatopathology referral center. With available data, we evaluated sex, primary location, histologic subtype, Breslow thickness, Clark level, presence of ulceration, associated lesion, and histologic subtype of the associated lesion.

RESULTS

Of 135,653 pathologic records from skin biopsy specimens over a 10-year period, 1,190 melanoma records were selected. Nevus-associated melanomas corresponded to 390 (32.8%) melanomas, with thin melanomas having a nevus 1.52 times the association observed with thick melanomas (>1.01 mm; 95% confidence interval, 1.16-1.99; P < .001). Superficial spreading melanoma was the most frequent, while no lentigo maligna melanoma was associated with nevi. The median Breslow thickness of nevus-associated melanomas was lower than that of de novo melanomas.

CONCLUSIONS

Nevus-associated melanomas, which represent one-third of the melanomas in southeast Brazil, are associated with intermittent sun exposure, superficial spreading melanomas, and lower Breslow thickness. This is one of the largest series describing nevus-associated melanomas in Latin America.

Identifying risk factors using a skin cancer screening program

BACKGROUND

The incidence of melanoma and nonmelanoma skin cancer continues to increase. To detect lesions at an earlier phase in their progression, skin cancer screening programs have been advocated by some. However, the effectiveness of skin cancer screening and the ideal population that these screenings should target have yet to be firmly established. This study details the relationship of a group of well-known risk factors with presumptive diagnoses in a large series of individuals self-referred for free skin cancer screening.

METHODS

Data obtained during 2007 to 2010 from a descriptive cross-sectional study skin cancer screening program are presented. Participant history was recorded using standardized medical history forms prior to skin examination. Screeners conducted a skin examination varying from whole-body to limited areas (per participant preference) and recorded diagnoses. Diagnoses were assigned to the nonmelanoma cancer (NMC) or suspicious pigmented lesion group for analysis.

RESULTS

A presumptive diagnosis of NMC was associated with male sex, age ≥ 50 years, personal history of skin cancer, lower skin phototype, increased sunscreen use, and increased chronic sun exposure (all P values ≤ .0001). After controlling for skin phototype, increased sunscreen use was not associated with a presumptive diagnosis of NMC (P = .96). Presumptive diagnosis of a suspicious pigmented lesion was associated with a reported history of "changing mole" (P < .0001) and negatively associated with age ≥ 50 years (P < .0001) and a personal history of skin cancer (P = .0119).

CONCLUSIONS

Several known risk factors for nonmelanoma skin cancer correlated with a presumptive diagnosis of NMC. The yield of presumptive atypical pigmented lesions was increased in participants aged < 50 years, supporting the notion that this population may benefit from screening.

Is prevention of cancer by sun exposure more than just the effect of vitamin D? A systematic review of epidemiological studies

The number of studies reporting on the association between sunlight exposure, vitamin D and cancer risk is steadily increasing. We reviewed all published case-control and cohort studies concerning colorectal-, prostate-, breast cancer, non-Hodgkin's lymphoma (NHL) and both sunlight and vitamin D to update our previous review and to verify if the epidemiological evidence is in line with the hypothesis that the possible preventive effect of sunlight on cancer might be mediated not only by vitamin D but also by other pathways. We found that almost all epidemiological studies suggest that chronic (not intermittent) sun exposure is associated with a reduced risk of colorectal-, breast-, prostate cancer and NHL. In colorectal- and to a lesser degree in breast cancer vitamin D levels were found to be inversely associated with cancer risk. In prostate cancer and NHL, however, no associations were found. These findings are discussed and it is concluded that the evidence that sunlight is a protective factor for colorectal-, prostate-, breast cancer and non-Hodgkin's lymphoma is still accumulating. The same conclusion can be drawn concerning high vitamin D levels and the risk of colorectal cancer and possibly breast cancer. Particularly in prostate cancer and NHL other sunlight potentiated and vitamin D independent pathways, such as modulation of the immune system and the circadian rhythm, and the degradation of folic acid might play a role in reduced cancer risk as well.

Radiotherapy as a risk factor for malignant melanoma after childhood skin hemangioma

The aim of this study was to determine therapy-related risk factors for the development of melanoma after hemangioma. A cohort study was conducted among 4620 patients treated before 16 years of age for skin hemangioma in France. A nested case-control study was also conducted on 13 patients who developed a melanoma (cases) matched with five controls in cohort according to sex, age at the hemangioma diagnostic, the calendar year of occurrence of the hemangioma, and follow-up. The radiation dose received at the site of the melanoma and at the same site in controls was estimated, and named 'local dose'. A total of 13 melanomas were registered during an average follow-up of overall 35 years, the risk of developing melanoma after a hemangioma treatment was 2.5-fold higher [95% confidence interval (CI): 1.4-4.1] compared with that of the general population, this ratio being only 0.8 (95% CI: 0.05-3.6) in 896 patients who did not receive radiotherapy, but 3.0 (95% CI: 1.6-5.1) after radiotherapy. When adjusting on sex, age, and year of the treatment and follow-up duration, melanoma risk was 11.9 (95% CI: 1.4-123) times higher in patients treated with ytrium 90 than in the ones who did not received radiotherapy. In the case-control study, the risk of melanoma was not linked to the local radiation dose. Indeed, the increase in melanoma risk was observed even for very low local doses. Compared with the corresponding skin areas in patients who did not receive radiotherapy, the ones having received less than 0.001 Gy had a melanoma risk of 3.9 (95% CI: 0.5-32) and those who received more than 0.01 Gy had a risk of 6.9 (0.5-99). This study suggests that radiation therapy of skin hemangioma increases the risk of further melanoma, but we were not able to evidence a relation with the local dose. Nevertheless, childhood treated for hemangioma should be considered at risk for developing melanoma and suspicious pigmented lesions should be carefully evaluated even far from treated areas.

Ethnicity and cutaneous melanoma in the city of Sao Paulo, Brazil: a case-control study

BACKGROUND

Over the last century the incidence of cutaneous melanoma has increased worldwide, a trend that has also been observed in Brazil. The identified risk factors for melanoma include the pattern of sun exposure, family history, and certain phenotypic features. In addition, the incidence of melanoma might be influenced by ethnicity. Like many countries, Brazil has high immigration rates and consequently a heterogeneous population. However, Brazil is unique among such countries in that the ethnic heterogeneity of its population is primarily attributable to admixture. This study aimed to evaluate the contribution of European ethnicity to the risk of cutaneous melanoma in Brazil.

METHODOLOGY/PRINCIPAL FINDINGS

We carried out a hospital-based case-control study in the metropolitan area of Sao Paulo, Brazil. We evaluated 424 hospitalized patients (202 melanoma patients and 222 control patients) regarding phenotypic features, sun exposure, and number of grandparents born in Europe. Through multivariate logistic regression analysis, we found the following variables to be independently associated with melanoma: grandparents born in Europe-Spain (OR = 3.01, 95% CI: 1.03-8.77), Italy (OR = 3.47, 95% CI: 1.41-8.57), a Germanic/Slavic country (OR = 3.06, 95% CI: 1.05-8.93), or ≥ 2 European countries (OR = 2.82, 95% CI: 1.06-7.47); eye color-light brown (OR = 1.99, 95% CI: 1.14-3.84) and green/blue (OR = 4.62; 95% CI 2.22-9.58); pigmented lesion removal (OR = 3.78; 95% CI: 2.21-6.49); no lifetime sunscreen use (OR = 3.08; 95% CI: 1.03-9.22); and lifetime severe sunburn (OR = 1.81; 95% CI: 1.03-3.19).

CONCLUSIONS

Our results indicate that European ancestry is a risk factor for cutaneous melanoma. Such risk appears to be related not only to skin type, eye color, and tanning capacity but also to others specific characteristics of European populations introduced in the New World by European immigrants.

Estimating the attributable fraction for melanoma: a meta-analysis of pigmentary characteristics and freckling

Epidemiologic research has demonstrated convincingly that certain pigmentary characteristics are associated with increased relative risks of melanoma; however there has been no comprehensive review to rank these characteristics in order of their importance on a population level. We conducted a systematic review of the literature and meta-analysis to quantify the contribution of pigmentary characteristics to melanoma, estimated by the population-attributable fraction (PAF). Eligible studies were those that permitted quantitative assessment of the association between histologically confirmed melanoma and hair colour, eye colour, skin phototype and presence of freckling; we identified 66 such studies using citation databases, followed by manual review of retrieved references. We calculated summary relative risks using weighted averages of the log RR, taking into account random effects, and used these to estimate the PAF. The pooled RRs for pigmentary characteristics were: 2.64 for red/red-blond, 2.0 for blond and 1.46 for light brown hair colour (vs. dark); 1.57 for blue/blue-grey and 1.51 for green/grey/hazel eye colour (vs. dark); 2.27, 1.99 and 1.35 for skin phototypes I, II and III respectively (vs. IV); and 1.99 for presence of freckling. The highest PAFs were observed for skin phototypes 1/II (0.27), presence of freckling (0.23), and blond hair colour (0.23). For eye colour, the PAF for blue/blue-grey eye colour was higher than for green/grey/hazel eye colour (0.18 vs. 0.13). The PAF of melanoma associated with red hair colour was 0.10. These estimates of melanoma burden attributable to pigmentary characteristics provide a basis for designing prevention strategies for melanoma.

Estimating the attributable fraction for cancer: A meta-analysis of nevi and melanoma

Epidemiologic research has shown convincingly that certain phenotypic attributes are associated with increased relative risks of melanoma. Although such findings have intrinsic utility, there have been few attempts to translate such knowledge into estimates of disease burden suitable for framing public health policy. We aimed to estimate the population attributable fraction (PAF) for melanoma associated with melanocytic nevi using relative risk estimates derived from a systematic review and meta-analysis. We identified eligible studies using citation databases, followed by manual review of retrieved references. Of 49 studies identified, 25 and 23, respectively, were included in meta-analyses of atypical and common nevi. For people with > or =1 atypical nevi, the summary relative risk was 3.63 (95% confidence interval, 2.85-4.62), with a PAF of 0.25. The relative risk increased by 1.017 (95% confidence interval, 1.014-1.020) for each common nevus; however, significant heterogeneity in risk estimates was observed. We estimated that 42% of melanomas were attributable to having > or =25 common nevi (PAF 25-49 nevi = 0.15; PAF > or =50 nevi = 0.27), whereas PAFs for low nevus counts were modest (PAF 0-10 nevi = 0.04; PAF 11-24 nevi = 0.07). We modeled PAF under scenarios of varying nevus prevalence; the highest melanoma burden was always among those with high nevus counts (PAF range of 0.31-0.62 for > or =25 common nevi). Patients with > or =25 common nevi and/or > or =1 atypical nevi are a high-risk group, which might be targeted for identification, screening, and education. This work is the necessary first step in designing targeted preventive strategies for melanoma, which must now be overlaid with information about cost and utility.

Sunburns and risk of cutaneous melanoma: does age matter? A comprehensive meta-analysis

PURPOSE

Sunburns are an important risk factor for melanoma and those occurring in childhood are often cited as posing the greatest risk. We conducted a meta-analysis to quantify the magnitude of association for melanoma and sunburns during childhood, adolescence, adulthood and over a lifetime.

METHODS

After reviewing over 1300 article titles and evaluating 270 articles in detail, we pooled odds ratios from 51 independent study populations for "ever" sunburned and risk of cutaneous melanoma. Among these, 26 studies reported results from dose-response analyses. Dose-response analyses were examined using both fixed-effects models and Bayesian random-effects models.

RESULTS

An increased risk of melanoma was seen with increasing number of sunburns for all time-periods (childhood, adolescence, adulthood, and lifetime). In an attempt to understand how risk between life-periods compares, we also report these same linear models on a scale of five sunburns per decade for each life-period. The magnitude of risk for five sunburns per decade is highest for adult and lifetime sunburns.

CONCLUSIONS

Overall, these results show an increased risk of melanoma with increasing number of sunburns during all life-periods, not just childhood. Prevention efforts should focus on reducing sunburns during all life-periods.

Screening Evaluation System--Europe (SESy_Europe) met skin cancer screening

Skin tumors are the most frequent malignancies in the white population worldwide and have reached the proportion of an epidemic disease. Since non-melanocytic skin cancers can be cured when timely detected, given that still malignant melanoma may have good prognosis if early diagnosed, and considering the key role of primary care in cancer screening advising and implementation, the international PACMeR study group (trial_01.3) adjourned SESy_Europe database in a version comprehensive of skin-malignancies screening indexing. The novel database provides standardized pre-codified translations of 2,331 parameters in eight languages (English, French, German, Greek, Italian, Romanian, Spanish and Turkish) and records the time elapsed from last skin examination, cause and frequency of skins examinations and stratifies skin cancer risk patterns by a systematic registering of risk factors. A comprehensive indexing of skin cancer screening practices among European countries may in fact turn helpful in programming future health policy and tailoring interventions.

Risk factors for presumptive melanoma in skin cancer screening: American Academy of Dermatology National Melanoma/Skin Cancer Screening Program experience 2001-2005

BACKGROUND

Since its inception in 1985, the American Academy of Dermatology (AAD) National Melanoma/Skin Cancer Screening Program has strived to enhance early detection of cutaneous malignant melanoma (MM) by providing nationwide skin cancer education campaigns in combination with free skin cancer screenings.

OBJECTIVE

To analyze the AAD screening data from 2001 to 2005 in order to identify factors associated with MM detection, and thereby derive a model of increased likelihood for MM detection through visual skin examinations at screenings.

MATERIALS AND METHODS

Patients completed a standardized AAD pre-screening form with historical and phenotypic information. Clinicians then recorded suspected clinical findings noted at visual skin examination. Statistical analyses were conducted using SPSS 14 (SPSS Inc., Chicago, Ill).

RESULTS

Five factors, which can be remembered with the acronym HARMM, independently increased the likelihood of suspected MM being found in the 362,804 persons screened: History of previous melanoma (odds ratio [OR] = 3.3; 95% confidence interval [CI], 2.9-3.8); Age over 50 (OR = 1.2; 95% CI, 1.1-1.3); Regular dermatologist absent (OR = 1.4; 95% CI, 1.3-1.5); Mole changing (OR = 2.0; 95% CI, 1.9-2.2); and Male gender (OR = 1.4; 95% CI, 1.3-1.5). Individuals at highest risk (4 or 5 factors) comprised only 5.8% of the total population, yet accounted for 13.6% of presumptive MM findings, and were 4.4 times (95% CI, 3.8-5.1) more likely to be diagnosed with suspected MM than individuals at lowest risk (0 or 1 factor). Receipt of a total skin examination at screening independently increased the likelihood for identifying suspected MM (OR = 1.4; 95% CI, 1.3-1.6). However, significantly fewer screenees in the highest risk group versus those in the lowest risk group underwent total skin examinations (53.7% vs 62.5%).

LIMITATIONS

Risk factors studied limited to variables collected in screenee enrollment form.

CONCLUSIONS

A higher-risk subgroup of the skin cancer screening population can be identified through assessment of MM risk factors using the HARMM criteria. Refocusing efforts to provide a total skin examination to those individuals with multiple risk factors has the potential to both reduce costs and increase yields for suspected MM in future mass screening initiatives.