Plantar melanoma: a case-control study in Paraguay

Pathogenic mechanisms and etiologic aspects of Mycobacterium avium subspecies paratuberculosis as an infectious cause of cutaneous melanoma

Infectious etiologies have previously been proposed as causes of both melanoma and non-melanoma skin cancer. This exploratory overview explains and presents the evidence for the hypothesis that a microorganism excreted in infected ruminant animal feces, Mycobacterium avium subspecies paratuberculosis (MAP), is the cause of some cases of cutaneous melanoma (CM). Occupational, residential, and recreational contact with MAP-contaminated feces, soil, sand, and natural bodies of water may confer a higher rate of CM. Included in our hypothesis are possible reasons for the differing rates and locations of CM in persons with white versus nonwhite skin, why CM develops underneath nails and in vulvar skin, why canine melanoma is an excellent model for human melanoma, and why the Bacille Calmette-Guérin (BCG) vaccine has demonstrated efficacy in the prevention and treatment of CM. The pathogenic mechanisms and etiologic aspects of MAP, as a transmittable agent underlying CM risk, are carefully deliberated in this paper. Imbalances in gut and skin bacteria, genetic risk factors, and vaccine prevention/therapy are also discussed, while acknowledging that the evidence for a causal association between MAP exposure and CM remains circumstantial.

Alcohol as a Non-UV Social-Environmental Risk Factor for Melanoma

Although cancer mortality has declined among the general population, the incidence of melanoma continues to rise. While identifying high-risk cohorts with genetic risk factors improves public health initiatives and clinical care management, recognizing modifiable risk factors such as social-environmental risk factors would also affect the methods of patient outreach and education. One major modifiable social-environmental risk factor associated with melanoma is ultraviolet (UV) radiation. However, not all forms of melanoma are correlated with sun exposure or occur in sun-exposed areas. Additionally, UV exposure is rarely associated with tumor progression. Another social-environmental factor, pregnancy, does not explain the sharply increased incidence of melanoma. Recent studies have demonstrated that alcohol consumption is positively linked with an increased risk of cancers, including melanoma. This perspective review paper summarizes epidemiological data correlating melanoma incidence with alcohol consumption, describes the biochemical mechanisms of ethanol metabolism, and discusses how ethanol and ethanol metabolites contribute to human cancer, including melanoma.

Alcohol, alcoholic beverages, and melanoma risk: a systematic literature review and dose-response meta-analysis

PURPOSE

Several studies in recent years have investigated the relationship between alcohol intake and melanoma risk, with conflicting results. To help clarify this issue, we conducted a literature review and dose-response meta-analysis of studies published until June 30th, 2017, that examined the association between alcohol intake (overall and by beverage type) and melanoma risk.

METHODS

We used random effect models with maximum likelihood estimation to calculate summary relative risk (SRR) and 95% confidence intervals (95%CI).

RESULTS

We included 20 independent studies (encompassing 10,555 melanoma cases and over 1.6 million non-cases/controls) published during 1986-2016, of which six had a prospective cohort study design. Adjustment for phenotypic characteristics and sunlight exposure was performed in 11 and nine studies, respectively. Alcohol intake was moderately associated with melanoma risk: the SRR were 1.29 (95% CI 1.14-1.45) for those in the highest vs. lowest category of current alcohol intake, and 1.96 (95% CI 1.02-3.76, I² = 0%) for cumulative intake. In the dose-response analysis, the increase in risk associated with a 10 g increment in daily alcohol intake was 1.07 (95% CI 1.03-1.11). Risk estimates did not differ by gender, study design and adjustment for confounders; between-studies heterogeneity was acceptable, and there was no evidence of publication bias.

CONCLUSIONS

Our findings suggest that alcohol drinking may be moderately associated with increased melanoma risk, although residual confounding and bias cannot be ruled out. Further research is needed to confirm these findings, clarify the role of the different alcohol sources, and investigate the interaction with known melanoma risk factors.

Malignant melanoma of sun-protected sites: a review of clinical, histological, and molecular features

In most cases of cutaneous melanoma, ultraviolet (UV) radiation is recognized as a prominent risk factor. Less is known regarding the mechanisms of mutagenesis for melanoma arising in sun-protected sites, such as acral and mucosal melanoma. Acral and mucosal melanoma share many common features, including a late age of onset, a broad radial growth phase with prominent lentiginous growth, the presence of field cancerization cells, and, in most cases, lack of a precursor nevus. In addition to early chromosomal instability, many of the same genes are also involved in these two distinct melanoma subtypes. To better understand non-UV-mediated pathogenesis in melanoma, we conducted a joint literature review of clinical, histological, and molecular features in acral and mucosal melanoma. We also reviewed the current literature regarding aberrations in KIT, PDGFRA, TERT, and other commonly involved genes. By comparing common features of these two subtypes, we suggest potential mechanisms underlying acral and/or mucosal melanoma and offer direction for future investigations.

Is UV an etiological factor of acral melanoma?

Ultraviolet (UV) radiation is a major environmental risk factor for melanoma, particularly among Caucasians. However, studies have generated conflicting results on the role of UV exposure in the development of acral melanoma, the most prevalent subtype of melanoma in non-Caucasians. In this review, we analyzed studies that have examined the relationship between acral melanoma and UV and show that acral melanoma has specific epidemiological and genetic characteristics, with a lower frequency or absence of UV-induced features. Therefore, we postulate that UV is probably not involved in the etiology of acral melanoma. However, further epidemiological and laboratory studies are required to fully address this controversial issue, which may lead to a better understanding of the pathogenesis and prevention of acral melanoma.

Brazilian guidelines for diagnosis, treatment and follow-up of primary cutaneous melanoma - Part II

The last Brazilian guidelines on melanoma were published in 2002. Development in diagnosis and treatment made updating necessary. The coordinators elaborated ten clinical questions, based on PICO system. A Medline search, according to specific MeSH terms for each of the 10 questions was performed and articles selected were classified from A to D according to level of scientific evidence. Based on the results, recommendations were defined and classified according to scientific strength. The present Guidelines were divided in two parts for editorial and publication reasons. In this second part, the following clinical questions were answered: 1) which patients with primary cutaneous melanoma benefit from sentinel lymph node biopsy? 2) Follow-up with body mapping is indicated for which patients? 3) Is preventive excision of acral nevi beneficious to patients? 4) Is preventive excision of giant congenital nevi beneficious to patients? 5) How should stages 0 and I primary cutaneous melanoma patients be followed?

Prognosis of acral melanoma: a series of 281 patients

BACKGROUND

Acral melanoma (AM) is an unusual malignancy with poor survival. This study defines a cohort of patients, treated at a single institution, and the factors associated with survival and comparison with nonacral cutaneous melanoma (NACM).

METHODS

All patients with AM presenting from 1995 to 2010 were identified from a prospectively maintained database. Analysis of clinicopathologic features of AM associated with disease-specific survival (DSS) was performed. A stratified, stage-matched survival analysis compared the outcome of 281 acral to 843 extremity NACM patients.

RESULTS

A total of 281 AM patients (170 volar, 111 subungual) were identified. Pathologic stage (p < 0.001), ulceration (p < 0.001), Breslow thickness (p < 0.001), and a positive sentinel lymph node (p < 0.001) were found to be poor prognostic indicators associated with DSS. In stage-matched analysis, AM had a worse DSS compared with NACM (hazard ratio 1.8; 95 % CI 1.2-2.7; p < 0.01).

CONCLUSIONS

This study represents the largest, single-institution series describing the characteristics and outcomes of AM. AM tumors exhibit aggressive histopathologic features associated with a poorer survival outcome. AM patients have an inferior survival than extremity NACM when matched for stage, perhaps reflecting inherent alterations in tumor biology. This warrants further investigation into the differences between acral and cutaneous melanoma.

Malignant melanomas on head/neck and foot: differences in time and latitudinal trends in Norway

BACKGROUND

Cutaneous malignant melanoma (CMM) incidence continues to increase in many parts of the world. Solar ultraviolet (UV) radiation is the main environmental risk factor for CMM. Different body locations are subjected to different doses and exposure patterns of solar UV. Time and latitudinal trends of CMMs on shielded and exposed skin give valuable information about the aetiology of these cancers. In this study, we have compared the time and latitudinal trends of CMM incidence on skin areas which are chronically (head and neck) and rarely (foot) exposed to UV radiation, to gain more information about the relationship between sun doses, exposure patterns and melanomagenesis.

METHODS

We have analysed epidemiological data from the Cancer Registry of Norway, for foot and head and neck CMM for two time periods: 1966-1986 and 1987-2007.

RESULTS

Cutaneous malignant melanoma incidence rate on head and neck has increased with time, while incidence rates of foot CMM have remained almost constant with time in Norway. There is a large north-south gradient in incidence rates of CMM on head and neck in Norway, while there is almost no north-south gradient for CMM incidence on foot.

CONCLUSIONS

Comparisons of time trends and latitudinal trends of the incidence rates of CMM on head/neck and on foot indicate that solar radiation plays a role in the induction of the former CMM but probably not for the latter.

Meta-analysis of risk factors for cutaneous melanoma according to anatomical site and clinico-pathological variant

A systematic meta-analysis was performed to evaluate if cutaneous melanoma (CM) risk factors differ depending on body site and histological type. Adjusted estimates were extracted from 24 observational studies, for a total of 16,180 cases. Multivariate random-effects models were used to obtain summary relative risk (RR) estimates for all risk factors by body site and histological type. Summary RRs suggest that high naevus counts are strongly associated with CM on usually not sun exposed sites (p<0.001) while different patterns of sun exposure show a tendency for higher RRs for CM on usually sun exposed sites than on other body sites (p=0.087). Continuous pattern was found to be significantly inversely associated with CM for unexposed sites (p=0.01). RRs also differed by body site for skin (p=0.01) and hair colour (p=0.01), and these differences could be attributed to gene variability. This finding seems to suggest different aetiologic pathways of melanoma development by anatomical site.

Multiple Primary Acral Melanomas in African-Americans: A Case Series and Review of the Literature

BACKGROUND

Although melanoma accounts for only 4% to 5% of all skin cancers in the United States, it causes most skin cancer-related deaths. We describe a unique group of African-American patients with multiple primary acral lentiginous melanomas (ALMs).

OBJECTIVE

The purpose of this study was to review the case histories and management of a cohort of patients in the Mohs practice of our dermatologic surgeon with multiple primary ALM.

METHODS

This is a case series of patients with multiple ALM identified by chart review from 2000 to 2005. A thorough review of the literature was performed.

RESULTS

Four patients, all African-American, were identified with multiple ALM. All patients were managed with excision or Mohs micrographic surgery utilizing permanent sections. None of the patients with ALM had melanomas at nonacral sites or other types of skin cancer. Several had acral melanosis. Information in the literature on patients with multiple primary acral melanomas was insufficient.

CONCLUSION

Patients with multiple acral melanomas have not, to our knowledge, been reported thus far. It can be extrapolated from current literature, however, that appropriate management of these patients, including staging work and surgical intervention, is to be determined by the individual characteristics of the melanoma and the patient's concomitant risk factors, if any.

Malignant melanoma in Chile: an unusual distribution of primary sites in men from low socioeconomic strata

BACKGROUND

Mortality from malignant melanoma (MM) has increased in Chile in the past decade. The location of MM lesions on the body has been correlated with prognosis and survival.

AIM

To review body site and gender relationships with histopathologically confirmed primary MM in Chile.

METHODS

Records of 575 cases presenting to 5 state hospitals from 1992 to 2001 were analysed.

RESULTS

There were 360 women and 215 men. Women showed a significantly higher number of MM on the legs, cheeks and arms, and in the genital area, whereas men showed a significantly higher number on the ears, backs of the hands, soles and feet. Men had a predilection for MM with a poor prognosis.

CONCLUSION

The different body site distribution of primary MM in men and women may be explained by a different pattern of sun exposure. Ethnic and genetic factors may also be involved. The predominant location of MM in women in Chile is similar to white populations, whereas the location in men is similar to that observed in black and Asian populations. These observations may be relevant to the high mortality of MM in Chilean men.

Meta-analysis of risk factors for cutaneous melanoma: I. Common and atypical naevi

A systematic meta-analysis of observational studies of melanoma and one of the most important risk factors, the number of naevi, was conducted in order to clarify aspects of the aetiology of this disease. Following a systematic literature search, relative risks (RRs) were extracted from 46 studies published before September 2002. Dose-response random effects models were used to obtain pooled estimates. Sub-group analysis and meta-regression were carried out to explore sources of between-study variation and bias. Sensitivity analyses investigated the reliability of the results and any publication bias. Number of common naevi was confirmed an important risk factor with a substantially increased risk associated with the presence of 101-120 naevi compared with <15 (pooled Relative Risk (RR) = 6.89; 95% Confidential Interval (CI): 4.63, 10.25) as was the number of atypical naevi (RR = 6.36 95%; CI: 3.80, 10.33; for 5 versus 0). The type of study and source of cases and controls were two study characteristics that significantly influenced the estimates. Case-control studies, in particular when the hospital was the source for cases or controls, appeared to present much lower and more precise estimates than cohort studies.

Risk of melanoma and vitamin A, coffee and alcohol: a case–control study from Italy

Limited information is available on the association between the risk of cutaneous malignant melanoma (CMM) and dietary factors. The issue was investigated using data from a case-control study conducted in Italy between 1992 and 1994, including 542 patients with incident, histologically confirmed CMM and 538 controls, admitted to the same hospitals as cases for non-dermatologic and non-neoplastic diseases. We found a significant inverse association between vitamin A intake and CMM risk. The multivariate odds ratio, after allowance for phenotypic characteristics and history of sunburns, for the highest, compared with the lowest, quartile of intake was 0.71 (95% confidence interval (CI) 0.50-1.02) for beta-carotene, 0.57 (95% CI 0.39-0.83) for retinol, and 0.51 (95% CI 0.35-0.74) for total vitamin A. We found no appreciable association of CMM risk with selected food items, including fish, meat, vegetables, fruit, dairy products, wholemeal bread, alcohol, coffee and tea drinking. Consumption of tea appeared to have a protective effect on CMM risk. The relations with measures of dietary vitamin A are, however, moderate compared with the associations between phenotypic characteristics, sun exposure and number of naevi and CMM risk.