Diagnosis Of Melanocytic Lesions Research Articles

Use of New Techniques in Addition to IHC Applied to the Diagnosis of Melanocytic Lesions, With Emphasis on CGH, FISH, and Mass Spectrometry

Melanoma remains one of the most aggressive forms of cutaneous malignancies. While its diagnosis based on histologic parameters is usually straight forward in most cases, distinguishing a melanoma from a melanocytic nevus can be challenging in some instances, especially when there are overlapping clinical and histopathologic features. Occasionally, melanomas can histologically mimic other tumors and even demonstration of melanocytic origin can be challenging. Thus, several ancillary tests may be employed to arrive at the correct diagnosis. The objective of this review is to summarize these tests, including the well-established and commonly used ones such as immunohistochemistry, with specific emphasis on emerging techniques such as comparative genomic hybridization, fluorescence in situ hybridization and imaging mass spectrometry.

Proliferation indices correlate with diagnosis and metastasis in diagnostically challenging melanocytic tumors

The diagnosis of melanocytic lesions remains a formidable challenge in dermatopathology. For diagnostically challenging lesions, ancillary tests are available to inform the diagnosis, including immunohistochemistry and molecular testing (particularly fluorescence in situ hybridization [FISH]). However, the test result that most robustly informs the diagnosis remains controversial. Thirty-seven diagnostically challenging melanocytic lesions from our consultation service were reviewed. Histopathologic, immunohistochemical, and second-generation FISH results (NeoGenomics; probes 6p25, 8q24, 11q13, 9p21, and centromere 9) were correlated with the final consensus diagnosis and clinical follow-up using logistic regression and Fisher exact test. Based on histopathologic and immunohistochemical features, cases were designated as "favor benign" (n=19) or "favor malignant" (n=18) by a consensus group of up to 7 dermatopathologists. The sensitivity of FISH for the diagnosis of melanoma was 39%, and the specificity was 84%. Univariate logistic regression models for a final diagnosis of melanoma showed that only increased Ki-67-positive dermal tumor cells (≥5%; P=.01) significantly correlated with the diagnosis of melanoma. FISH result did not correlate with the final diagnosis (melanoma or nevus; P=.26). Follow-up (range, 8-29months) was available for 35 cases (19 diagnosed as nevus and 16 as melanoma), and metastases (restricted to sentinel lymph nodes) were detected from 5 melanomas (3 FISH negative and 2 FISH positive). Only increased dermal mitotic figures (>1/mm(2)) correlated with metastases to sentinel lymph nodes (P=.04). Thus, in the classification of diagnostically challenging melanocytic lesions, indices of proliferation emerge as the most informative diagnostic adjuncts-correlating with diagnosis and clinical behavior, respectively.

Combined Use of Ex Vivo Dermoscopy and Histopathology for the Diagnosis of Melanocytic Tumors

Dermoscopy can be applied to fixed tissues, and dermoscopic patterns correlate with microscopic findings. Data on the influence of ex vivo dermoscopy on pathologic diagnosis of melanocytic lesions are limited. Therefore, we aimed to determine whether this technique could aid on the histopathological evaluation of melanocytic neoplasms. Sequential cutaneous excisional biopsies of melanocytic lesions and their corresponding ex vivo dermoscopic images were prospectively analyzed. Additional sectioning was executed in areas of dermoscopic concern, having, by reference, a dermoscopic mapping of the sectioned specimens. Diagnostic differences before and after analyzing the new dermoscopy-guided sections were registered. A total of 564 melanocytic lesions were examined, and additional cuts were considered necessary in 84 (14.9%) cases. Of these, 11 lesions (13.1%) had a different final diagnosis after dermoscopy-guided specimen sectioning, including 3 lesions that were reclassified as melanomas and 2 melanomas that were restaged. We found that the combined use of ex vivo dermoscopy and histopathology improves clinical-pathological correlation and allows selection of representative areas for sectioning. Altogether, this technique may improve diagnostic confidence and accuracy in the histopathological evaluation of melanocytic lesions.

The utility of dermoscopy-guided histologic sectioning for the diagnosis of melanocytic lesions: A case-control study

Dermoscopy allows for visualization of morphologic structures beyond the epidermis, including features that may indicate early malignant transformation. However, dermoscopic features are rarely considered during routine histologic sectioning, and areas of clinical concern may be missed during microscopic evaluation. We assessed the diagnostic impact of a dermoscopy-guided micropunch score for the evaluation of melanocytic lesions. In this case-control study, we evaluated 150 scored melanocytic lesions. Original tissue specimens were reprocessed to create a control group, in which a new score was introduced elsewhereinthe lesion to guide an alternative plane of section. Slides were reviewed in a randomized, double-blinded manner to assess histologic features and render a diagnosis. Dermoscopy was also reviewed. The proportion of cases with a higher grade in the original, dermoscopy-guided section was statistically significant. Four invasive melanomas were exclusively identified using the scoring protocol. The presence of regression structures, negative pigment network, radial streaming or pseudopods, and irregular blotches were highly specific for a higher diagnostic grade. This study is retrospective and reprocessing tissue does not perfectly mimic routine sectioning. Dermoscopy can identify important, histologically high-grade areas, and this information can be used to optimize the sectioning of melanocytic neoplasms.

Reticulin immunostaining revisited.

Introduction:Reticulin staining has been suggested as an inexpensive tool in the differential diagnosis of melanoma versus benign nevi. In the present study, reticulin immunostaining patterns in malignant melanomas, benign intradermal nevi, and blue nevi were observed. The concordance in evaluation of the pattern between observers was also done.Materials and Methods:A retrospective search was performed in the computer database of the Ackerman Academy of Dermatopathology for “melanoma,” “melanocytic nevus,” and “blue nevus”. Fifty-six melanomas (30 of nodular subtype and 26 of superficial spreading subtype), 54 benign compound nevi, and 27 blue nevi were selected for the study. Patterns of reticulin staining in the dermis and the basement membrane in these melanocytic lesions were evaluated and the concordance between the two groups of authors was assessed. Statistical evaluation was performed with the Statistica® 10 program, Tulsa, OK. Concordance of the pattern evaluation was evaluated using Cohen's kappa coefficient.Results:Melanomas show a variable basement membrane pattern some of which show flat, thin and smooth pattern. Benign nevi almost never showed this flat pattern at the basement membrane zone. In the dermis, melanomas showed reticulin fibers surrounding groups of melanocytic cells while nevi predominantly had reticulin fibers around individual cells. There was greater agreement in evaluating the dermal component compared to the basement membrane pattern.Conclusion:The dermal reticulin staining pattern may be of some value in the diagnosis of melanocytic lesions, but poor concordance in evaluation of the basement membrane zone pattern limits its usefulness.

Report of two cases of vacuolar interface dermatitis initially suspected as melanomain situand review of the literature

The diagnosis of melanocytic lesions can be challenging and immunohistochemical study is a valuable tool for dermatopathologists. We report two cases initially simulating melanoma in situ, reviewing the histopathological and immunohistochemical findings and the cases published in the literature with similar findings/results. We emphasize the importance of clinicopathological correlation in the evaluation of lesions with interface changes and in the pseudomelanocytic nests, which may simulate melanoma in situ. We also highlight the importance of using a immunohistochemistry panel in addition to Melan-A, in the study of these lesions.

Kızılötesi Işık ile Atipik Nevus ve Malign Melanom Tesbiti

Objective: The aim of this study is to handle the subjectivity of clinical observations in the diagnosis of dysplastic nevi and malignant melanoma, by using an alternative spectrophotometric method to simple dermatoscopic examination. Material and Methods: Images taken by CCD (Charge-coupled Device) camera with a 1280x1024 pixel resolution which is capable of taking snapshot images between 400-1000 nm wavelengths were converted to 2048x2560 size data and were subjected to digital image processing. For each lesion, three different images were captured at selected infrared wavelenghts of 770 nm, 810 nm, 850 nm and one image with visible light. Risk score analysis of the digital image processing was carried out on two main parameters. One is surface area risk score (SAR) and the other is pixel intensity risk score (PIR). The same lesions are also evaluated dermatoscopically and ABCD scores of each lesion were calculated. Results: Thirty nine patients with 47 pigmented lesions were included in the study. When all the statistical data were put together, positive correlation with ABCD scores is stronger for the images at 770 nm than the ones with 810 nm. Also when we consider all parameters which have been studied separately, the most meaningful correlation with ABCD scores was shown by “total surface area risk score”. Conclusion: Wavelengths of 770 nm and 850 nm seem to be optimal in terms of correlating with ABCD scores of the lesions. Also we need to determine the optimum wavelength range for the accurate diagnosis of melanocytic lesions.

Classification of reticular pattern and streaks in dermoscopic images based on texture analysis.

The early detection of melanoma is one of the greatest challenges in clinical practice of dermatology, and the reticular pattern is one of the most important dermoscopic structures to improve melanocytic lesion diagnosis. A texture-based approach is developed for the automatic detection of reticular patterns, whose output will assist clinical decision-making. Feature selection was based on the use of two algorithms by means of the classical graylevel co-occurrence matrix and Laws energy masks optimized on a set of 104 dermoscopy images. The AdaBoost (adaptive boosting) approach to machine learning was used within this strategy. Results suggest superiority of LEM for reticular pattern detection in dermoscopic images, achieving a sensitivity of 90.16% and a specificity of 86.67%. The use of automatic classification in dermoscopy to support clinicians is a strong tool to assist diagnosis; however, the use of automatic classification as a complementary tool in clinical routine requires algorithms with high levels of sensitivity and specificity. The results presented in this work will contribute to achieving this goal.

FTIR microspectroscopic characterization of Spitz nevi

In the last 10years, few efforts have been carried out to apply vibrational spectroscopy in the study of dermal pathologies in order to characterize the most relevant spectral markers for distinguishing benign from cancerous lesions.Spitz nevi are a special group of benign melanocytic lesions, characterized by spindled and/or epithelioid nevomelanocytes, with peculiar clinical, dermoscopic and histopathological features. The “atypical forms” of Spitz nevi are among the commonest problems of differential diagnosis with the so-called “spitzoid melanomas”. The clinical and histological criteria for discriminating these two entities are very subtle and often still quite subjective, and, in a significant percentage of cases, can lead to diagnostic pitfalls and inadequate therapies. Therefore, it is noteworthy to outline that the diagnosis of melanocytic lesions still represents a challenging problem and a continue matter of discussion.We exploited FTIR microspectroscopy to study the different kinds of spitzoid melanocytes, in order to define the most relevant spectral markers of each specimen and to achieve objective information on “borderline” histologically atypical lesions. In particular, the spectroscopic investigation was carried out on melanocytes deriving from normal skin (as a normal control), malignant melanoma and Spitz nevi. The presence of the characteristic bands of melanin was investigated, too.

Discordance in histopathologic evaluation of melanoma sentinel lymph node biopsy with clinical follow-up: results from a prospectively collected database.

Sentinel lymph node (SLN) status currently represents the single most important prognostic factor in clinically localized melanoma and is widely used in patients with melanoma at significant risk for nodal micrometastasis. Although several studies have looked at the rates and implications of inaccuracies in the histopathologic diagnosis of melanocytic lesions, accuracy in the histologic interpretation of the SLN in melanoma has not been addressed. The goal of this study was to determine the rates of discordance in the histopathologic evaluation of the SLN and the potential clinical impact on patients referred to a comprehensive melanoma center. A prospectively collected database was queried for melanoma patients who had SLN biopsies performed at outside institutions before referral to the University of Michigan Multidisciplinary Melanoma Program between 2006 and 2009. These cases were reviewed and clinical follow-up obtained. After internal review of the SLN material, 13 (8%) of 167 cases had major discrepancies in diagnosis that impacted patient management and prognosis. The disease of five patients was subsequently downstaged and the disease of eight patients was upstaged after internal review of the SLNs and reversal in diagnoses. There appears to be a small yet significant rate of discordance in diagnosis of the SLN for melanoma after expert histopathologic review. The implications of this discordance and revision of diagnosis is substantial. Expert histopathologic review of the SLN warrants consideration to provide the most accurate prognostic information and optimal patient care.

The influence of a gene expression signature on the diagnosis and recommended treatment of melanocytic tumors by dermatopathologists.

TPS9111 Background: Many studies have documented suboptimal accuracy and reproducibility in the diagnosis of melanocytic lesions by histopathology, even by experienced dermatopathologists. Therefor...

Balloon cell nevus of the iris

Balloon cell nevus is a rare histopathological lesion characterized by a predominance of large, vesicular and clear cells, called balloon cells. There is only 1 case of balloon cell nevus of the iris reported in the literature. Case reportA 55 year-old man presented a pigmented elevated lesion in the right iris since the age of 12 years old. The lesion had been growing for the past 2 years and excision was performed. Histopathological examination showed a balloon cell nevus composed of clear and vacuolated cells without atypia. A typical spindle cell nevus of the iris was also observed. The differential diagnosis included xanthomatous lesions, brown adipocyte or other adipocytic lesions, clear cell hidradenoma, metastatic clear cell carcinoma of the kidney and clear cell sarcoma. The tumor was positive for Melan A, S100 protein and HMB45. ConclusionBalloon cell nevus of the iris is rare but should be considered in the differential diagnosis of melanocytic lesions of the iris.

Usefulness of a Red Chromagen in the Diagnosis of Melanocytic Lesions of the Conjunctiva

Immunohistochemical analyses may assist in the diagnosis of precancerous and cancerous conjunctival lesions. To use Vector Red (VR) to identify an immunologic marker that is sensitive for all melanocytes and another that is sensitive and specific for activated and/or atypical conjunctival melanocytic lesions (MLs). Eight specimens each of control lesions (normal conjunctiva and normal uvea as well as choroidal melanoma) and 8 from the diagnostic categories (conjunctival nevus, primary acquired melanosis with mild or no atypia, primary acquired melanosis with moderate to severe atypia, and conjunctival melanoma) that provided sufficient quantity and quality of tissue were available for processing. The specimens were obtained from the Ophthalmic Pathology Laboratory, The Ottawa Hospital, from 2005 to 2013. The specimens were immunolabeled with human melanoma black 45 (HMB45), melanoma antigen recognized by T cells 1 (Melan-A), S100, and Ki67 using VR and a double panmelanoma cocktail (dPANMEL) using 3,3′-diaminobenzidine (DAB) and VR. The HMB45-immunolabeled specimens were additionally developed with DAB, with and without overnight bleaching with hydrogen peroxide, 4%. Data were collected by 2 pathologists who were masked to sample grouping. Differentiation between benign and malignant MLs based on immunomarker profile. Immunoreactivity was best visualized in specimens with VR. Melan-A labeled all melanocytes (100% sensitivity; panmelanocyte marker) without discriminating between benign and malignant lesions (0% specificity). Atypical melanocytes were most specifically labeled with HMB45 (96% specificity, 97% sensitivity; atypia marker). In primary acquired melanosis specimens, we found that the percentage of HMB45 (P < .001), S100 (P < .001), and Ki67 (P ≤ .02) positivity increased significantly with worsening atypia. We recommend VR, which rarely requires specimen bleaching, as the standard substrate for immunohistochemical analysis of conjunctival MLs. We found Melan-A and HMB45 to best characterize MLs. In conjunctival MLs, the use of VR with Melan-A and HMB45 provides substantial sensitivity for all melanocytes and for atypical melanocytes, respectively, and reduces specimen-processing time for laboratories performing immunohistochemistry on MLs.

Ras, Raf, and MAP Kinase in Melanoma

A growing understanding of the biology and molecular mechanisms of melanoma has led to the identification of a number of driver mutations for this aggressive tumor. The most common mutations affect signaling of the Ras/Raf/MAPK (mitogen-activated protein kinase) pathway. This review will focus on mutations in genes encoding proteins that play a role in the MAPK pathway and that have been implicated in melanoma biology, such as BRAF, NRAS, and MEK (MAPK kinase), and detail the current understanding of their role in melanoma progression from a molecular biology perspective. Furthermore, this review will also consider some additional mutations in genes such as KIT, GNAQ, and GNA11, which can be seen in certain subtypes of melanoma and whose gene products interact with the MAPK pathway. In addition, the association of these molecular changes with clinical and classical histopathologic characteristics of melanoma will be outlined and their role in diagnosis of melanocytic lesions discussed. Finally, a basic overview of the current targeted therapy landscape, as far as relevant to the pathologist, will be provided.

Preparation and Application of Amino- and Dextran-Modified Superparamagnetic Iron Oxide Nanoparticles

Amino-dextran-functionalized superparamagnetic iron oxide nanoparticles (SPION) were synthesized by two-steps: Dextran-modified SPION was obtained by “one-step” co-precipitation method. Then, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS) was added to the resultant dextran-SPION to prepare amino-dextran-functionalized SPION (AEAPS/Dex-SPION). The particles were characterized by vibrating sample magnetometer (VSM), transmission electron micrographs (TEM), atomic force micrographs (AFM), gas chromatography and atomic absorption spectrophotometry. The size of the modified particles varied in a range of 30 to 40 nm and did not change significantly after modification. The binding rate of AEAPS was 91.15%. A monoclonal antibody against S100 (anti-S-100), a gold standard for the diagnosis of melanocytic lesions, was conjugated to the AEAPS/Dex-SPION to prepare immuno-SPION. From the result in melanoma B16 cell, the immuno-SPION was proven to have a bio-targeting activity. Such AEAPS/Dex-SPION might be very useful for bio-magnetically targeted detection in early melanocytic lesions.

Combined fluorescence‐Raman spectroscopic setup for the diagnosis of melanocytic lesions

Two optical fibre-based probes for spectroscopic measurements on human tissues were designed and developed. The two probes combine fluorescence and Raman spectroscopy in a multimodal approach. The fluorescence excitation was provided by two laser diodes emitting in the UV (378 nm) and in the visible (445 nm) range, while a third source in the NIR (785 nm) was used for Raman. The device was tested on freshly excised human skin biopsies clinically diagnosed as malignant melanoma, melanocytic nevus, or healthy skin. Discrimination of lesions based on their fluorescence and Raman spectra showed good correlation with the subsequent histological examination.

Correlation Between Histologic Assessment and Fluorescence In Situ Hybridization Using MelanoSITE in Evaluation of Histologically Ambiguous Melanocytic Lesions

The 4-probe, multicolor, fluorescence in situ hybridization (FISH) panel targeting chromosomes 6 and 11 has shown promising sensitivity and specificity in distinguishing between benign nevi and malignant melanoma. Only a few studies have assessed the potential utility of FISH in classification of histologically ambiguous melanocytic lesions. In the United States, this assay is exclusively licensed to NeoGenomics Laboratories (Irvine, California), which provides the technical component and has developed an innovative service (MelanoSITE) allowing pathologists to interpret FISH results using a dedicated Web portal. Thus far, use of MelanoSITE as a diagnostic adjunct in the diagnosis of melanocytic lesions has not, to our knowledge, been reported in the literature. To analyze 1.5 years of experience with the MelanoSITE melanoma FISH assay in the evaluation of histologically ambiguous lesions in the context of second opinion and routine dermatopathology practice. A prospective histologic/FISH correlation study of 140 cases. Twenty-seven percent of abnormal FISH results were false-positive results because of tetraploidy. After correcting for known false-positive results, all lesions considered atypical nevi showed normal FISH signals. Abnormal FISH signals were reported in 30% of lesions considered histologically borderline and in 48% of lesions in which a diagnosis of melanoma was favored. Four-probe, multicolor FISH results for melanoma correlate with the microscopic assessments of histologically ambiguous lesions. Pathologists using MelanoSITE must be aware of the high rate of false-positive results from tetraploidy.

Agreement of Dermatopathologists in the Evaluation of Clinically Difficult Melanocytic Lesions: How Golden Is the ‘Gold Standard’?

Background: The ‘gold standard’ for the diagnosis of melanocytic lesions is dermatopathology. Although most of the diagnostic criteria are clearly defined, the interpretation of histopathology slides may be subject to interobserver variability. Objectives: The aim of this study was to determine the variability among dermatopathologists in the interpretation of clinically difficult melanocytic lesions. Methods: This study used the database of MelaFind®, a computer-vision system for the diagnosis of melanoma. All lesions were surgically removed and sent for independent evaluation by four dermatopathologists. Agreement was calculated using kappa statistics. Results: A total of 1,249 pigmented melanocytic lesions were included. There was a substantial agreement among expert dermatopathologists: two-category kappa was 0.80 (melanoma vs. non-melanoma) and three-category kappa was 0.62 (malignant vs. borderline vs. benign melanocytic lesions). The agreement was significantly greater for patients ≥40 years (three-category kappa = 0.67) than for younger patients (kappa = 0.49). In addition, the agreement was significantly lower for patients with atypical mole syndrome (AMS) (kappa = 0.31) than for patients without AMS (kappa = 0.76). Limitations: The data were limited by the inclusion/exclusion criteria of the MelaFind® study. This might represent a selection bias. The agreement was evaluated using kappa statistics. This is a standard method for evaluating agreement among pathologists, but might be considered controversial by some statisticians. Conclusions: Expert dermatopathologists have a high level of agreement when diagnosing clinically difficult melanocytic lesions. However, even among expert dermatopathologists, the current ‘gold standard’ is not perfect. Our results indicate that lesions from younger patients and patients with AMS may be more problematic for the dermatopathologists, suggesting that improved diagnostic criteria are needed for such patients.

The Remote Assessment of Melanocytic Skin Lesions: A Viable Alternative to Face-to-Face Consultation

Background: The incidence of melanoma continues to rise in the Western world, prompting health care professionals to search for novel tools that may increase rates of early detection. Here we focus on one such tool: remote specialist diagnosis of melanocytic lesions utilising mobile-phone camera patient-generated clinical images. Objective: We aim to test the hypothesis that patient-generated clinical images utilising mobile phones are of acceptable quality, and that digital image diagnostic outcomes are comparable with face-to-face (FTF) diagnostic outcomes. Methods: Study participants were asked to photograph, using their mobile-phone camera any number of their own melanocytic naevi, and then upload these clinical images to a central server. Diagnostic accuracy of the management decision based on assessing these digital images was tested by comparing results from digital image assessment with results from FTF assessments. Results: We provide evidence that suggests potential patients are capable of uploading good quality clinical images of melanocytic lesions for diagnostic purposes, and we show that good concordance rates can be achieved with respect to digital image and FTF diagnostic outcomes. With respect to the latter, exact agreement was found in 116 of 167 assessable lesions (69%). Conclusions: This work suggests that specialist remote diagnosis of patient-generated clinical images of melanocytic lesions utilising mobile-phone cameras may be a viable alternative to traditional FTF assessments.

Basic dermoscopy of melanocytic lesions for beginners

Dermoscopy is a safe, easy-to-repeat diagnostic method used especially in the diagnosis of melanocytic lesions and others. Performing dermoscopy for skin lesions on the whole body takes only one minute more than standard clinical examination. Therefore the knowledge of basic dermoscopy among multi-specialization doctors - from general practitioners, surgeons, oncologists to dermatologists - increases the possibility of detection of potential melanoma. To describe the basic aspects of dermoscopy of melanocytic lesions. Review of medical databases PubMed and Medline from the last 8 years and a retrospective analysis of own experience. We report the fundamental principles of performing dermoscopy, basic dermoscopic features and diagnostic algorithms of selected melanocytic lesions. Conclusions. The knowledge base of dermoscopy is very important among doctors of many specializations. It increases melanoma detection in very early stages.