Early melanoma detection: nonuniform dermoscopic features and growth

Exploring Small-Diameter Melanomas: A Retrospective Study on Clinical and Dermoscopic Features

BACKGROUND

Early melanoma detection allows for timely intervention and treatment, significantly improving the chances of favorable outcomes for patients. Small-diameter melanoma (SDM) typically represents an initial growth phase of cutaneous melanoma. One of the challenges in detecting melanoma in their early stage lies in the fact that dermoscopy criteria have been primarily designed for fully developed lesions. Early-stage melanomas may be difficult to detect and possibly even be overlooked or misinterpreted during examinations.

METHODS

The primary aim of this study was to identify valuable clinical and dermoscopic clues to enhance the detection of SDMs. To achieve this objective, we conducted a comprehensive retrospective analysis, including forty SDMs with a diameter of 5 mm or less. These cases were diagnosed over an 8-year period and were collected from five referral centers across Brazil. Seven experienced dermatologists independently assessed the dermoscopic features of each lesion. Additionally, this study includes demographic and histological information.

RESULTS

The study encompassed a total of 28 patients, of which 16 were females, accounting for 58% of the participants, with an average age of 43.6 years. Among the small-diameter melanomas (SDMs) under investigation, the majority, constituting 27 cases (69.2%), were identified as "de novo" lesions, i.e., not associated with a nevus. Additionally, eight SDMs (20%) exhibited invasive characteristics, with Breslow index measurements ranging between 0.2 to 0.4 mm, suggesting an early stage of malignancy. During dermoscopic examinations, the most prevalent features observed were irregular dots and globules, present in 95% and 87.5% of cases, respectively. Moreover, brown structureless areas were identified in 70% of lesions, followed by atypical network (67.5%), pseudopods (55%), dotted vessels (47.5%), flat structureless blue-gray areas (42.5%), and irregular blotches (40%). Notably, all SDM were diagnosed in patients under surveillance through total body skin photography (TBSP) and Digital Dermoscopy (DD).

CONCLUSIONS

Dermoscopy significantly enhances the diagnostic accuracy of melanoma, even in its early stages. Particularly for high-risk patients with numerous nevi, the identification of a new lesion or subtle changes on dermoscopy during follow-up may serve as the sole clue for an early diagnosis. This emphasizes the critical role of dermoscopy in SDM detection and reinforces the importance of surveillance in high-risk patients for timely and effective management.

Machine learning based skin lesion segmentation method with novel borders and hair removal techniques

The effective segmentation of lesion(s) from dermoscopic skin images assists the Computer-Aided Diagnosis (CAD) systems in improving the diagnosing rate of skin cancer. The results of the existing skin lesion segmentation techniques are not up to the mark for dermoscopic images with artifacts like varying size corner borders with color similar to lesion(s) and/or hairs having low contrast with surrounding background. To improve the results of the existing skin lesion segmentation techniques for such kinds of dermoscopic images, an effective skin lesion segmentation method is proposed in this research work. The proposed method searches for the presence of corner borders in the given dermoscopc image and removes them if found otherwise it starts searching for the presence of hairs on it and eliminate them if present. Next, it enhances the resultant image using state-of-the-art image enhancement method and segments lesion from it using machine learning technique namely, GrabCut method. The proposed method was tested on PH2 and ISIC 2018 datasets containing 200 images each and its accuracy was measured with two evaluation metrics, i.e., Jaccard index, and Dice index. The evaluation results show that our proposed skin lesion segmentation method obtained Jaccard Index of 0.77, 0.80 and Dice index of 0.87, 0.82 values on PH2, and ISIC2018 datasets, respectively, which are better than state-of-the-art skin lesion segmentation techniques.

Dermoscopic 'Chaos and Clues' in the diagnosis of melanoma in situ

BACKGROUND/OBJECTIVE

To describe the dermoscopic features of melanoma in situ using the Chaos and Clues method.

METHOD

Histologically proven primary melanoma in situ (MIS) diagnosed through a specialist teledermoscopy clinic were reviewed by three dermatologists. By consensus they agreed on the global dermoscopic pattern, colours, presence of chaos (asymmetry of colour and structure and more than one pattern), and each of the nine clues described for malignancy.

RESULTS

One hundred MIS in 92 patients of European ethnicity (45 males) were assessed. Mean age was 67.3 years (range 20-95). The mean dimensions of the lesions were 11.1 × 12.0 mm (range 2.5-31.3 × 2.3-32.3 mm). Using pattern analysis, 82% of the lesions had three or more patterns (multicomponent) and the rest had 2 patterns. Colours included light brown (100%), dark brown (98%) and grey (75%). All MIS demonstrated chaos. The most prevalent clues were thick lines (88%), eccentric structureless areas (88%), and grey or blue structures (75%).

CONCLUSION

Dermoscopy can be very helpful in the early diagnosis of melanoma and MIS. The Chaos and Clues method is simple to use. Its unambiguous descriptors can be successfully used to describe MIS. The presence of chaos and clues to malignancy (including thick lines, eccentric structureless areas, and blue/grey structures) should raise a red flag and lead to referral or excision.

Melanocytic nevi and melanoma: unraveling a complex relationship

Approximately 33% of melanomas are derived directly from benign, melanocytic nevi. Despite this, the vast majority of melanocytic nevi, which typically form as a result of BRAF^V600E-activating mutations, will never progress to melanoma. Herein, we synthesize basic scientific insights and data from mouse models with common observations from clinical practice to comprehensively review melanocytic nevus biology. In particular, we focus on the mechanisms by which growth arrest is established after BRAF^V600E mutation. Means by which growth arrest can be overcome and how melanocytic nevi relate to melanoma are also considered. Finally, we present a new conceptual paradigm for understanding the growth arrest of melanocytic nevi in vivo termed stable clonal expansion. This review builds upon the canonical hypothesis of oncogene-induced senescence in growth arrest and tumor suppression in melanocytic nevi and melanoma.

Methods of Melanoma Detection

Detection and removal of melanoma, before it has metastasized, dramatically improves prognosis and survival. The purpose of this chapter is to (1) summarize current methods of melanoma detection and (2) review state-of-the-art detection methods and technologies that have the potential to reduce melanoma mortality. Current strategies for the detection of melanoma range from population-based educational campaigns and screening to the use of algorithm-driven imaging technologies and performance of assays that identify markers of transformation. This chapter will begin by describing state-of-the-art methods for educating and increasing awareness of at-risk individuals and for performing comprehensive screening examinations. Standard and advanced photographic methods designed to improve reliability and reproducibility of the clinical examination will also be reviewed. Devices that magnify and/or enhance malignant features of individual melanocytic lesions (and algorithms that are available to interpret the results obtained from these devices) will be compared and contrasted. In vivo confocal microscopy and other cellular-level in vivo technologies will be compared to traditional tissue biopsy, and the role of a noninvasive "optical biopsy" in the clinical setting will be discussed. Finally, cellular and molecular methods that have been applied to the diagnosis of melanoma, such as comparative genomic hybridization (CGH), fluorescent in situ hybridization (FISH), and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), will be discussed.

Conceptual approach to early melanoma detection: models, tools, issues and challenges

Identification and removal of melanoma early in its development remains the most effective treatment. However, identification of early melanoma remains challenging and may result in unnecessary morbidity due to the excess excision of benign melanocytic nevi. Herein, we present a conceptual model of benign and malignant melanocytic growths. The potential differences in the location of the cell of origin as well as considerations for neoplasm progression are also reviewed. Several of the clinical tools currently available, the integration of information from those different sources, and approaches to set an optimum biopsy threshold are discussed. While early detection remains a challenge, significant progress has been made. Insight into melanoma growth processes and appropriate use of available tools can result in the detection of thinner melanomas while also decreasing overall biopsy rates.

Dermoscopy of small melanomas: just miniaturized dermoscopy?

BACKGROUND

Small malignant melanomas (MMs) are usually MMs in an initial growth phase, deserving attention by the clinician aiming at an early diagnosis.

OBJECTIVES

To identify clues for early diagnosis of small MMs, by comparing the dermoscopic features of MMs < 4 mm (micromelanomas) with those of larger MMs.

METHODS

Our database consists of dermoscopic images of 482 MMs, which have been retrieved and measured digitally. The ABCD (asymmetry, border, colour, dimension) and 7-point criteria were evaluated for the whole database by three expert dermoscopists, whereas the main dermoscopic pattern was assessed only for micromelanomas. The dermoscopic aspects were correlated to clinical and histological features.

RESULTS

Most 7-point and ABCD scores, and criteria referring to micromelanomas, differed from those of the MM database as a whole. Lesion asymmetry, number of colours, blue-whitish veil, atypical vessels, irregular globules/dots and regression increased according to MM diameter. An inverse trend was observed for atypical network and irregular pigmentation, which were more frequently observed in micromelanomas than in larger ones. Among the 22 micromelanomas, 12 lesions were in situ, whereas the other 10 were 0·2-2 mm thick. The clinical and dermoscopic characteristics of the two groups were similar.

CONCLUSIONS

Micromelanomas are not a rarity. However, the clinician should be aware of the fact that the majority of them lack most of the dermoscopic features presented by larger lesions.

Histologic outcomes of excised moderate and severe dysplastic nevi

BACKGROUND

Dysplastic nevi (DN) have been a matter of controversy since their initial description in 1978 because of differences in the clinical and histological terminology, and large studies on histological outcomes of excising moderate to severely DN have not previously been described.

OBJECTIVE

To determine the clinical characteristics of DN and histologic outcomes of excised moderate and severe DN.

METHODS

Retrospective chart review of patients with DN or Clark's nevi at the Dermatology Department at Rutgers-Robert Wood Johnson Medical School in Somerset, New Jersey, from January 2009 to June 2012. Three hundred ninety-three lesions from 380 patients were included in this study.

MAIN OUTCOME MEASURE

Histologic results of excised moderate and severe DN.

RESULTS

Thirty-four percent of DN were excised because of the presence of moderate or severe atypia, personal history of melanoma, or both. None of the excised lesions showed evidence of melanoma; 81.6% of excisions showed scar or granulation tissue. Only 14% of excised lesions were found to have residual lesions, and 4.4% showed recurrent nevi.

CONCLUSION

In 134 excisions of moderate to severe DN, no melanoma was identified. Most of the excisions showed scar or granulation tissue. The rate of residual lesions after shave biopsy of moderate or severe DN was lower than after punch biopsy.

The dysplastic nevus: from historical perspective to management in the modern era: part I. Historical, histologic, and clinical aspects

Since its description in the 1970s, the dysplastic nevus has been a source of confusion, and whether it represents a precursor to melanoma remains a controversial subject. Although a Consensus Conference in 1992 recommended that the term "dysplastic nevus" no longer be used, the histologic diagnosis continues to present a therapeutic quandary for dermatologists and other physicians, and there remains significant variation in clinical management. In part I of this continuing medical education review, we will discuss the historical origins of the term, the evidence for its distinct histologic basis, and its clinical significance.

Dysplastic nevi

Dysplastic nevi have been a subject of much debate since their original description in 1978. Although some question the biological potential of dysplastic nevi themselves, several studies have shown that their presence confers substantial risk for melanoma. In addition to predisposing patients to melanoma, dysplastic nevi have been shown to harbor genetic mutations, indicating their position on a continuum between banal nevi and melanomas. Dysplastic nevi are also clinically relevant as mimickers of melanoma, and can be challenging diagnostically. This article reviews the history, epidemiology, biology and genetics, clinical features, histopathologic features, and management guidelines for patients with these lesions.

Melanoma in situ in a private practice setting 2005 through 2009: location, lesion size, lack of concern

BACKGROUND

Studies have shown that the incidence of melanoma in situ (MIS) is increasing significantly.

OBJECTIVE

This study analyzes selected clinical and demographic characteristics of MIS cases observed in private dermatology practices in the United States.

METHODS

This study collected 257 MIS cases from 4 private dermatology practices in the United States from January 2005 through December 2009, recording age, gender, anatomic location, lesion size, patient-reported change in lesion, and concern about lesion. Case totals for invasive melanoma during the same period were recorded.

RESULTS

The data collected showed a higher incidence of MIS in sun-exposed areas of older patients, especially men. The median age of patients at the time of MIS detection was 69 years. The most common site for MIS was the head-neck region. The number of MIS cases collected exceeded the number of invasive malignant melanoma cases during the study period, with an observed ratio of 1.35:1.

LIMITATIONS

For 136 patients, data were collected retrospectively for lesion size, location, gender, and age. For these patients, patient-reported change in lesion and concern about lesion were not collected. Patients often did not consent to a full body examination, therefore, it is possible that MIS lesions may have been missed in double-clothed areas.

CONCLUSION

Careful attention to pigmented lesions, even lesions less than 4 mm, on sun-exposed areas, including scalp, trunk, and feet, will facilitate earlier diagnosis of MIS. As only 30.4% of male patients and 50% of female patients had concern about these lesions, it still falls to the dermatologist to discover MIS.

A decade of melanomas: identification of factors associated with delayed detection in an academic group practice

BACKGROUND

Melanoma incidence is increasing, but the effect of various clinical factors on tumor stage is unclear.

OBJECTIVE

To review histologic and clinical features of melanomas diagnosed in our group over a 10-year period to determine trends in diagnosis and lesion derivation, predictive value of clinical lesion size, and effect of physician and patient concerns before biopsy.

METHOD

Relevant pathology reports and physician clinic notes were reviewed for 572 melanomas.

RESULT

From 1999 to 2008, melanoma biopsies increased significantly more than nevus biopsies and patient visits. Melanomas predominantly (81%) arose de novo, with remaining lesions as likely to arise from common as dysplastic nevi. Melanomas were detected at twice the rate, and at earlier stage, in established as in new patients. Clinical size of invasive melanomas was related to lesion depth. For 64% of melanomas, patient and physician concern drove the decision to biopsy, whereas 1.4% of melanomas were biopsied only for patient concern.

CONCLUSION

The increase in melanoma diagnoses was largely due to increases in cases of lentigo maligna on the head and neck. Delayed detection was associated with location on trunk and extremities, new patient status, patient concern before biopsy, and physician suspicion of nonmelanoma skin cancer.

Benefits of total body photography and digital dermatoscopy ("two-step method of digital follow-up") in the early diagnosis of melanoma in patients at high risk for melanoma

BACKGROUND

Early detection of melanoma is the best way to improve prognosis. Digital follow-up (DFU) programs of populations at high risk could be an efficient strategy for detecting early melanomas with low morbidity.

OBJECTIVE

We sought to report the added value of the use of the "two-step method" (digital total body photography and digital dermatoscopy).

METHODS

This was an analysis of the surveillance of 618 patients at high risk for melanoma included in our DFU program from 1999 to 2008.

RESULTS

A total of 11,396 lesions were monitored (mean 18.44/patient) during a median follow-up of 96 months (median 10 visits/patient). A total of 1152 lesions, 1.86 per patient, were excised. Almost 70% (798) were lesions previously registered at least twice, whereas 356 (30%) were detected and removed in the same visit. During follow-up, 98 melanomas (8.5% of excised lesions) were diagnosed in 78 patients (12.6%). In all, 53 melanomas were in situ (53.3%), whereas invasive (45) showed a Breslow index of less than 1 mm (median 0.5 mm) and none were ulcerated.

LIMITATIONS

Because there are no control groups we cannot determine if the combined use of total body photography and digital dermatoscopy is more beneficial than these techniques used separately.

CONCLUSION

DFU with total body photography and dermatoscopy in a selected population at high risk demonstrated the early detection of melanomas with a low rate of excisions. Long-term follow-up is required to allow the detection of slow-growing melanomas. Based on our 10-year experience, melanomas can be diagnosed at any time, suggesting that in a population at high risk for melanoma, DFU should be maintained over time.

Advances and short comings in the early diagnosis of melanoma

Malignant melanoma kills more people each year than any other skin cancer, with approximately 8000 lives lost and a cost of over 3 billion dollars annually in the US alone. Tumor depth is the most important prognostic factor in melanoma. Thus, early detection has the potential to diagnose melanoma when lesions are thinner, and to improve survival in primary melanomas. In this review, we discuss the implications, barriers, and advantages of melanoma screening, and describe the currently employed methods of detection, newly available modalities, and current areas of research. We also discuss the efficacy, advantages and disadvantages, and clinical practicality of each, and suggest various means of combining different methodologies as well as tailoring various strategies to individual patient needs.

Atypical mole syndrome and dysplastic nevi: identification of populations at risk for developing melanoma - review article

Atypical Mole Syndrome is the most important phenotypic risk factor for developing cutaneous melanoma, a malignancy that accounts for about 80% of deaths from skin cancer. Because the diagnosis of melanoma at an early stage is of great prognostic relevance, the identification of Atypical Mole Syndrome carriers is essential, as well as the creation of recommended preventative measures that must be taken by these patients.

Comparative analysis of total body and dermatoscopic photographic monitoring of nevi in similar patient populations at risk for cutaneous melanoma

BACKGROUND

Our previous experience monitoring nevi in high-risk patients using serial digital epiluminescence microscopy (DELM) photography achieved low biopsy rates but was limited by melanomas presenting as new lesions or arising from nevi that had not been photographed.

OBJECTIVE

To determine whether biopsy rates, efficiency of melanoma detection, and melanoma origin (de novo vs nevus derived) differed in a similar patient population monitored using total body (TB) photography.

METHODS

One thousand seventy-six patients (including 187 from a prior cohort) underwent TB photography and were monitored using photographs obtained at the initial visit. Risk factors and median monitoring periods for these patients were comparable with those of patients previously monitored using DELM photography.

RESULTS

Two hundred seventy-five biopsies were performed in 467 patients on follow-up visits. Of 12 melanomas detected on follow-up, five were invasive, five presented as changing lesions and two as new lesions, nine arose de novo, and the remainder were nevus derived.

CONCLUSIONS

In our experience with both approaches, monitoring patients at risk for melanoma using TB photography was associated with lower biopsy rates and lower nevus-to-melanoma ratios than using DELM and facilitated detection of new and changing lesions. In both cohorts, the majority of melanomas detected on follow-up arose de novo.

Melanoma: Stem cells, sun exposure and hallmarks for carcinogenesis, molecular concepts and future clinical implications

Background:

The classification and prognostic assessment of melanoma is currently based on morphologic and histopathologic biomarkers. Availability of an increasing number of molecular biomarkers provides the potential for redefining diagnostic and prognostic categories and utilizing pharmacogenomics for the treatment of patients. The aim of the present review is to provide a basis that will allow the construction–or reconstruction–of future melanoma research.

Methods:

We critically review the common medical databases (PubMed, EMBASE, Scopus and Cochrane CENTRAL) for studies reporting on molecular biomarkers for melanoma. Results are discussed along the hallmarks proposed for malignant transformation by Hanahan and Weinberg. We further discuss the genetic basis of melanoma with regard to the possible stem cell origin of melanoma cells and the role of sunlight in melanoma carcinogenesis.

Results:

Melanocyte precursors undergo several genome changes –UV-induced or not– which could be either mutations or epigenetic. These changes provide stem cells with abilities to self-invoke growth signals, to suppress antigrowth signals, to avoid apoptosis, to replicate without limit, to invade, proliferate and sustain angiogenesis. Melanocyte stem cells are able to progressively collect these changes in their genome. These new potential functions, drive melanocyte precursors to the epidermis were they proliferate and might cause benign nevi. In the epidermis, they are still capable of acquiring new traits via changes to their genome. With time, such changes could add up to transform a melanocyte precursor to a malignant melanoma stem cell.

Conclusions:

Melanoma cannot be considered a “black box” for researchers anymore. Current trends in the diagnosis and prognosis of melanoma are to individualize treatment based on molecular biomarkers. Pharmacogenomics constitute a promising field with regard to melanoma patients' treatment. Finally, development of novel monoclonal antibodies is expected to complement melanoma patient care while a number of investigational vaccines could find their way into everyday oncology practice.

Strategies for early melanoma detection: Approaches to the patient with nevi

Given its propensity to metastasize and the lack of effective therapies for most patients with advanced disease, early detection of melanoma is a clinical imperative. Although there are no noninvasive techniques for the definitive diagnosis of melanoma, and the "gold standard" remains biopsy with histologic examination, a variety of modalities may facilitate early melanoma diagnosis and the detection of new and changing nevi. This article reviews the general clinical principles of early melanoma detection and various modalities that are currently available or on the horizon, providing the clinician with an up to date understanding of management strategies for their patients with numerous or atypical nevi.

LEARNING OBJECTIVE

After completing this learning activity, participants should understand the clinical importance of early melanoma detection, appreciate the challenges of early melanoma diagnosis and which patients are at highest risk, know the general principles of early melanoma detection, be familiar with current and emerging modalities that may facilitate early melanoma diagnosis and the detection of new and changing nevi, know the advantages and limitations of each modality, and be able to practice a combined approach to the patient with numerous or clinically atypical nevi.

The value of screening in melanoma

The incidence of cutaneous melanoma has increased substantially in most white populations during the past several decades. Despite improvements in the early recognition of melanoma and the use of novel diagnostic techniques that enhance our diagnostic capabilities, disease-related mortality remains a significant public health issue. In the absence of effective treatment approaches for advanced disease, the best means for reducing deaths by melanoma are screening as well as professional and public education. The role of population-or community-based screening remains controversial, but evidence from self-selected screening campaigns, health care professional surveillance, and specialized pigmented lesions clinics underscores the value of screening and early detection programs, particularly in high-risk groups. Annual screening campaigns coupled with intense media promotion have become commonplace in many countries, and despite their low yield of melanoma detection, the dissemination of educational material and information to the public during these events is important in increasing public awareness. Future directions should include using screening campaigns to target middle-aged and older men and persons of lower socioeconomic status, who suffer most from the burden of the disease and its associated mortality. On a worldwide scale, comprehensive educational and screening campaigns should be implemented or intensified in underserved areas and geographic regions with lower survival rates, such as Eastern European countries. A better understanding of the biology of the disease, already occurring with notable strides, will help us to define better those individuals who will benefit most from screening and early detection efforts. Technologic advances and new diagnostic modalities will afford a more reliable and vigilant surveillance of high-risk individuals, whereas the wide use of the Internet will enhance the distribution of relevant information to the public with the ultimate goal of achieving a better control of melanoma.

The "dysplastic" nevus

Dysplastic nevi have become an increasing focus clinically, with evidence that they are associated with a higher risk of developing melanoma. However, there still is contention regarding the significance of dysplastic nevi. This contribution provides an overview of the history, epidemiology, genetics, clinical and histologic features, and procedures for clinical management of dysplastic nevi. Since dysplastic nevi were described originally in 1978, a great deal of research has examined the epidemiology of these lesions and the genetic factors related to the development of dysplastic nevi. However, there is disagreement regarding the clinical management of dysplastic nevi and the histologic definition of dysplastic nevi. Current recommendations include preventative measures, such as sun protection and careful surveillance and biopsies of suspicious lesions as needed. The advent of new technologies, such as computer-vision systems, have the potential to significantly change treatment of dysplastic nevi in the future.

Melanoma, nevogenesis, and stem cell biology

It is now well established that a subpopulation of tumor stem cells (TSCs) are present within cancer tissues. This suggests that tumors evolve from stem cells; however, the exact cell of tumor origin, the potential role of dedifferentiation, and the role of plasticity in tumor development are largely unknown. A model cancer for the study of the oncologic process is melanoma. The developmental biology of melanocytes is relatively well understood, the cells pigment as they differentiate making them easy to identify, and benign and malignant tumors develop on the skin surface allowing direct observation of growth features, early detection, and removal. This ready access to early-stage tumors will facilitate study of the early oncologic processes and the role of tissue stem cells. Melanomas, like other cancers, include a subpopulation of TSCs. These TSCs have access to embryologic developmental programs, including the capacity to differentiate along multiple cell lineages. For example, melanomas can activate germ-cell pathways with major implications for TSC self-renewal through the activation of telomerase and genomic instability through the collision of meiotic and mitotic pathways (meiomitosis). The TSC model is still evolving, but the existence of TSCs has significant ramifications for tumor development, diagnosis, prognosis, and treatment of melanoma and other cancers.

Cancer stem cells and human malignant melanoma

Cancer stem cells (CSC) have been identified in hematological malignancies and several solid cancers. Similar to physiological stem cells, CSC are capable of self-renewal and differentiation and have the potential for indefinite proliferation, a function through which they may cause tumor growth. Although conventional anti-cancer treatments might eradicate most malignant cells in a tumor, they are potentially ineffective against chemoresistant CSC, which may ultimately be responsible for recurrence and progression. Human malignant melanoma is a highly aggressive and drug-resistant cancer. Detection of tumor heterogeneity, undifferentiated molecular signatures, and increased tumorigenicity of melanoma subsets with embryonic-like differentiation plasticity strongly suggest the presence and involvement of malignant melanoma stem cells (MMSC) in the initiation and propagation of this malignancy. Here, we review these findings in the context of functional properties ascribed to melanocyte stem cells and CSC in other cancers. We discuss the association of deregulated signaling pathways, genomic instability, and vasculogenic mimicry phenomena observed in melanoma subpopulations in light of the CSC concept. We propose that a subset of MMSC may be responsible for melanoma therapy-resistance, tumor invasiveness, and neoplastic progression and that targeted abrogation of a MMSC compartment could therefore ultimately lead to stable remissions and perhaps cures of metastatic melanoma.

Digital dermoscopic monitoring of atypical nevi in patients at risk for melanoma

BACKGROUND

Atypical nevi are a common risk factor for melanoma.

OBJECTIVES

The objective was to determine the utility of monitoring dermoscopic photographs of atypical nevi in a high-risk population.

METHODS

Over a 4.5-year period, digital dermoscopic photographs were taken of clinically atypical nevi at initial and follow-up visits, such that side-by-side comparisons could be made.

RESULTS

A total of 5,945 lesions were monitored in 297 patients over 3 to 52 months (median, 22 months), and 324 lesions were biopsied. Photographic (dermoscopic) changes were noted in 96 of 5,945 (1.6%) lesions, which included 64 dysplastic nevi (67%), 25 common nevi (26%), and 1 melanoma (1.0%). Of 6 melanomas biopsied during the follow-up period, only 1 was detected by dermoscopic photographic change at follow-up.

CONCLUSIONS

Most clinically atypical melanocytic nevi are stable over time, and lesions exhibiting dermoscopic changes are most likely to be dysplastic nevi. Although dermoscopy is a useful tool for clinical examination, the sensitivity of dermoscopic monitoring is limited by melanomas that may arise in normal skin or in clinically benign nevi that were not initially photographed.

Screening, early detection, and trends for melanoma: Current status (2000-2006) and future directions

In the past 5 years, there have been notable strides toward the earlier recognition and discovery of melanoma, including new technologies to complement and augment the clinical examination and new insights to help clinicians recognize early melanoma. However, incidence and mortality rates throughout most of the developed world have risen over the past 25 years, while education and screening, potentially the best means for reducing the disease, continue to be severely underutilized. Much progress needs to be made to reach middle-aged and older men and persons of lower socioeconomic status who suffer a disproportionate burden of death from melanoma. Worldwide melanoma control must also be a priority, and comprehensive educational and screening programs should be directed to Northern Ireland and a number of Eastern European nations, whose 5-year survival rates range between 53% and 60%, mirroring those of the United States and Australia more than 40 years ago.

LEARNING OBJECTIVE

After completing this learning activity, participants should be aware of the most recent melanoma epidemiologic data, both in the United States and internationally; worldwide early detection and screening programs; clinical strategies to recognize and improve the detection of early melanoma; the latest technologies for early detection of melanoma; and public and professional education programs designed to enhance early detection.

Dermoscopic Features of Difficult Melanoma

BACKGROUND

The dermoscopic diagnosis of cutaneous melanoma (CM) may be difficult because some CM lack specific dermoscopic features for melanoma diagnosis.

OBJECTIVE

To evaluate whether a diagnosis of CM could be achieved using the classic dermoscopic melanoma-specific criteria, we conducted a retrospective multicenter study of 508 CM samples.

METHODS

All the dermoscopic images were analyzed to identify the dermoscopic criteria found in dermoscopically difficult melanomas (DDM) and to examine the possible relation of dermoscopic diagnosis with respect to the difficulty of the dermoscopic diagnosis and the melanoma thickness.

RESULTS

A significant percentage of melanomas, 89 of 508 (17.5%), were DDM. The criteria leading to a significant increased risk of DDM were presence of streaks [odds ratio (OR), 2.26; 95% confidence interval (CI), 1.15-4.47), absence or presence of regular pigmentation (OR, 3.41; 95% CI, 1.70-6.85), absence of a blue-whitish veil (OR, 4.04; 95% CI, 2.33-6.99), absence of regression structures (OR, 4.31; 95% CI, 2.42-7.66), and the presence of hypopigmentation (OR, 2.61; 95% CI, 1.49-4.58).

CONCLUSION

A significant number of melanomas defy even dermoscopic diagnosis. Only a meticulous comparative and interactive process based on an assessment of all the individual's other nevi ("ugly ducking" sign) and a knowledge about recent changes can lead to the recognition of DDM.

Clinical selection of melanocytic lesions for dermoscopy decreases the identification of suspicious lesions in comparison with dermoscopy without clinical preselection

BACKGROUND

In most cases dermoscopy is performed only on lesions selected by clinical inspection which present worrying clinical features or appear to deviate from the patient's average type of naevus. Thus, possible early malignant melanomas (MMs) or MM precursors, lacking typical clinical characteristics, may elude the dermoscopic examination.

OBJECTIVES

To perform a comparison between two different approaches to the patient's examination, one based on a clinical preselection of lesions to be examined by dermoscopy, and the other consisting of the dermoscopic scrutiny of all melanocytic lesions with a diameter>or=2 mm (total dermoscopy).

METHODS

Sixty-three consecutive patients with MM, undergoing periodic dermoscopic examinations of their naevi, were enrolled in the study. The patients first underwent an assessment of the entire skin with the unaided eye for the identification of lesions for dermoscopy. Subsequently, the patients underwent dermoscopic examination of all melanocytic lesions. Images of naevi identified by clinical examination or by total dermoscopy as having dermoscopic aspects characteristic of a suspicious lesion, i.e. necessitating either surgical excision or follow-up examinations, were separately recorded, classified and described employing the ABCD rule of dermoscopy and the seven-point checklist.

RESULTS

Five hundred and fifty-one lesions were chosen by clinical inspection for subsequent dermoscopic examination; among these, 117 were considered for excision or follow-up. Ninety-two further lesions were identified for excision or follow-up by employing only total dermoscopy. Dermoscopy scores of lesions selected by clinical inspection plus dermoscopy were similar to those identified by dermoscopy alone. In the former group, 13 lesions showed either an ABCD or a seven-point score corresponding to a suspicious lesion, whereas eight such lesions were identified only by total dermoscopy. Thus, by clinical selection plus dermoscopy we were able to identify only 62% of dermoscopically suspicious lesions.

CONCLUSIONS

Clinical selection of melanocytic lesions for dermoscopic examination is associated with the 'loss' of a conspicuous number of lesions which deserve surgical excision or follow-up examinations. Total dermoscopy, enabling the detection of suspicious lesions, together with storage, retrieval and sequential comparison of their images, could enhance MM diagnosis by follow-up, in comparison with clinical preselection for dermoscopy.

Colorimetric analysis of pigmented skin lesions: a pilot study with the Visi-Chroma VC-100 device

BACKGROUND

Definition of the colour of pigmented skin lesions (PSLs) with the naked eye remains subjective and may be influenced by lighting. This problem underlines the usefulness of instrumental assessments such as epiluminescence microscopy and colorimetric devices.

OBJECTIVE AND METHODS

We describe here a new method of colour analysis of PSLs with the Visi-Chroma VC-100 device, which illuminates the surface of the skin with white light-emitting diodes (LEDs) and analyses the reflected light by a red-green-blue (RGB) charge-coupled device (CCD) colour camera. Twenty-one PSLs to be excised for cosmetic or medical reasons were analysed by this device with clinicopathological correlation.

CONCLUSIONS

This method is feasible and might be useful to assess the colour of PSLs and allow comparisons for changes over time. Further studies are needed to determine the usefulness of this device in clinical practice.

Melanoma, a Tumor Based on a Mutant Stem Cell?

Stem cells play a critical role in normal tissue maintenance, and mutations in these stem cells may give rise to cancer. We hypothesize that melanoma develops from a mutated stem cell and therefore residual stem cell characteristics should be able to be identified in melanoma cell lines. We studied three metastatic melanoma cell lines that exhibited multiple morphologic forms in culture and demonstrated the capacity to pigment. We used the ability to efflux Hoechst 33342 dye, a technique known to enrich for stem cells in many tissues, to segregate cell populations. The cells with the greatest ability to efflux the dye were (1) small in size, (2) had the capacity to give rise to larger cell forms, and (3) had the greatest ability to expand in culture. The small cells were found to have a decreased proliferative rate and were less melanized. Large dendritic cells that appeared to be nonproliferative were identified in cultures. Treatment with cytosine beta-D-arabinofuranoside hydrochloride (Ara-C) expanded the large cell population but the residual proliferative capacity, both in vitro and in vivo, remained concentrated in the smaller cell fraction. Antigenic staining patterns were variable and heterogeneous. Nestin (a neural stem cell marker) and gp100 (premelanosomal marker) favored the smaller cell population, while nerve growth factor receptor often labeled larger cells. Morphologic and antigenic heterogeneity remained intact after clonal purification. These findings are consistent with the behavior expected for a tumor based on stem cell biology; this finding has diagnostic and therapeutic implications for melanocytic neoplasias.

Cutaneous melanoma and intervention strategies to reduce tumor-related mortality: what we know, what we don't know, and what we think we know that isn't so

The care of patients who have cutaneous melanoma (CM) has undergone a dramatic change during the past five decades. In an increasing majority of cases, CM is being discovered in a premetastatic phase of tumor progression. Most patients are being treated in the ambulatory setting with a minimum of inconvenience and economic cost, and modest re-excision margins have largely replaced the mutilating surgical exonerations that were once standard only four decades ago. Histopathologic assessment of the primary tumor is the most widely used staging procedure to determine who is most likely to develop metastatic disease. For patients who develop distant metastases, there is no therapy currently available, based on large-scale randomized trials, that will prolong patient survival. Therefore, establishing an early diagnosis in a premetastatic phase of tumor development must be the overriding goal of any intervention strategy that seeks to reduce CM-related mortality. Unfortunately, as a result of public messages that emphasize the role of ultraviolet radiation (UVR) exposure in tumor development, most general physicians and lay people believe that most if not all cases of CM are the direct result of UVR exposure. In fact, we do not know the case fraction of CM directly attributable to UVR, and the unintended consequences of current messages directly linking UVR exposure and CM development may be thwarting the primary intervention goal of reducing tumor-related mortality. More likely to have an immediate positive impact on CM-related mortality are public messages that encourage skin awareness and self-examination by patients, total skin screening examinations by physicians during routine care, and periodic lifetime surveillance of patients determined to have a high CM risk based on identifiable historic and phenotypic traits.

Dysplastic naevus vs. in situ melanoma: digital dermoscopy analysis

BACKGROUND

To date, much confusion exists about the biological significance of dysplastic naevi and about the relationship between melanocytic dysplasia and clinical atypia.

OBJECTIVES

To use a digital dermoscopy analyser with a series of 'borderline' pigmented skin lesions (i.e. dysplastic naevi and in situ melanomas) to find correlation between the studied variables and to determine their discriminating power with respect to histological diagnosis.

METHODS

The pigmented skin lesions (n = 174) were histologically examined by three experienced dermatopathologists and identified as in situ melanomas (n = 38) and dysplastic naevi (n = 136). The system evaluated 48 parameters as possible discriminant variables, grouped into four categories: geometry, colours, textures and islands of colour. Once the lesions were analysed (stepwise discriminant analysis), sensitivity, specificity and accuracy were calculated.

RESULTS

At the end of the stepwise procedure the percentage of cases classified correctly was 71.8%. Of 136 dysplastic naevi only 98 were classified correctly, while 27 of 38 in situ melanomas were recognized correctly.

CONCLUSIONS

We conclude that there are so far no digital dermoscopic criteria that can clearly distinguish dysplastic naevi from in situ melanomas.

Invasive superficial spreading melanomas arising from clinically normal skin

We provide documentation of the onset of 3 invasive superficial spreading melanomas arising from clinically normal skin and correlation with histologic lack of nevus association. Clinical, dermoscopic, and pathologic features of these "de novo" melanomas, which became invasive while small in diameter and had few clinical criteria for diagnosis, are reported.

Dermoscopy for skin cancer detection

PURPOSE OF REVIEW

The worldwide incidence of melanoma and nonmelanoma skin cancers is increasing alarmingly. The development of new techniques such as dermoscopy leads to a consequent progress in skin cancers screening. The purpose of this review is to highlight recent advances in dermoscopy, reviewing primary research articles published in the last year.

RECENT FINDINGS

With the recent standardization of diagnostic procedures obtained by the Consensus Net Meeting on Dermoscopy and the definition of new melanoma-specific criteria, the efficacy in early melanoma diagnosis is improved. Dermoscopy is cost effective, leading to a decreased number of excised benign lesions, and the dermoscopic follow-up allows early detection of melanomas. However, the technique must be performed by experts in order not to miss melanomas. For this reason, instruction in dermoscopy is mandatory. Moreover, computer-aided diagnosis has been tested to be a valid support for physicians. Teledermoscopy is a new tool that allows a second expert opinion to manage atypical lesions.

SUMMARY

Dermoscopy opens up a new dimension on clinical morphology of skin lesions. Digital follow-up examinations, computer-aided diagnosis, and teledermoscopy are new facilities that will change the current management of skin cancers in general and melanoma in particular. Dermoscopy in the hands of experienced physicians has higher discriminatory power than naked-eye examination to detect skin cancers.

Melanomas detected with the aid of total cutaneous photography

BACKGROUND

Early detection of melanoma results in excision of thinner melanomas, which are associated with better prognosis. Total cutaneous photography provides a temporal comparison of lesions, which allows clinicians and patients to recognize new and subtly changing lesions.

OBJECTIVES

We examined the utility of total cutaneous photography in detecting melanoma, identified the reason for biopsy of suspicious lesions and determined who detected new melanomas, the physician on follow-up examination or the patient on self-examination.

PATIENTS/METHODS

The charts of the 576 patients in the total cutaneous photography database were reviewed. Twelve patients were identified who had melanoma diagnosed with photographic assistance. Baseline and prebiopsy photographs, dermatology clinic notes (115 patient visits) and pathology reports for each biopsied lesion were reviewed. Histological diagnosis, cause for biopsy, and whether the lesion was detected by the patient or physician, was recorded for each of the biopsied lesions. Also noted were all the lesions that concerned patients, the cause for concern, and whether these lesions were biopsied.

RESULTS

A total of 93 lesions were biopsied in these patients. Twenty-seven (35%) of 77 melanocytic lesions were histologically diagnosed as melanoma. The thickest melanoma found measured 1.1 mm, indicating a favourable prognosis in our patients. Seventy-four per cent of the melanomas were biopsied due to changes from baseline and 19% were biopsied because they were new lesions. The changes noted were subtle and the lesions that proved to be melanoma did not satisfy the classical clinical criteria for melanoma. Eight (30%) of the melanomas were identified by patients on skin self-examination. Twenty-six per cent of the lesions that concerned patients were not biopsied after evaluation by a physician.

CONCLUSIONS

We found that photographically assisted follow-up helped detect new and subtly changing melanomas, which did not satisfy the classical clinical features of melanoma. In addition, photographically assisted follow-up helped detect nonmelanoma skin cancers. Patient skin self-examination proved to be valuable, in that it complemented physician follow-up examination in detecting melanomas. Photographic follow-up was also valuable in avoiding unnecessary biopsy in suspicious, but stable lesions. Total cutaneous photography therefore may be an effective way to increase the sensitivity and specificity for detecting melanoma.