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.     

Examination of Lesions (Including Dermoscopy) without Contact with the Patient Is Associated with Improper Management in about 30% of Equivocal Melanomas

BACKGROUND: In clinical practice, decisions regarding management of a pigmented skin lesion are based on morphologic examination, as well as on anamnestic, emotional, and medicolegal aspects. In some cases, the "ugly duckling" sign may be an indication for excision of a morphologically featureless melanoma. Therefore, examination of pigmented skin lesions based on clinical and dermoscopic images, without contact with the patient, may be associated with a not negligible risk of incorrect lesion management. OBJECTIVE: In this study, we tried to assess to what extent lesion management based on purely morphologic examination diverges from optimal management based on in vivo examination with direct contact with the patient, lesion history, and clinical and dermoscopic evaluation. METHODS: The study included clinical and dermoscopic images of 100 diagnostically equivocal pigmented lesions, including 20 early melanomas and 5 pigmented basal cell carcinomas consecutively referred for surgery; the images were reviewed by six dermatologists who specialize in melanoma screening and were previously trained in dermoscopy. RESULTS: The percentage of melanomas correctly classified was less than 50% both for naked eye and combined examination. Regarding lesion management, only about 70% of malignancies (melanomas and basal cell carcinomas) are correctly referred for surgery by observers. Similar results have been obtained focusing on melanoma (72.5%). CONCLUSION: Facing difficulties in diagnosing pigmented skin tumors, lesion management based on the morphology of the lesion, even including dermoscopic images, but without direct contact with the patient, diverges greatly from the gold standard management established by face-to-face examination and comports a not negligible risk of leaving a melanoma unexcised.     

Appearance of New Vemurafenib-associated Melanocytic Nevi on Normal-appearing Skin: Case Series and a Review of Changing or New Pigmented Lesions in Patients with Metastatic Malignant Melanoma After Initiating Treatment with Vemurafenib

Background: Vemurafenib, a selective BRAF inhibitor that has antineoplastic activity in patients with unresectable or metastatic malignant melanoma whose tumor harbors a BRAF V600E mutation, has multiple drug-associated cutaneous adverse effects. Purpose: To provide a detailed and comprehensive review of reported changing or new pigmented lesions in oncology patients who have been treated with vemurafenib. Methods: The new appearance of melanocytic nevi on normal-appearing skin after initiating treatment with vemurafenib is described in two men with metastatic malignant melanoma whose tumors demonstrated a BRAF V600E mutation. Using the PubMed database, an extensive literature search was performed for the following topics: vermurafenib, nevus, nevi, melanoma, pigmented lesion, cutaneous, adverse effect, side effect. The results of the search were used to secure all reports of new or changing pigmented lesions after initiating treatment with vemurafenib. Results: Vemurafenib is associated with both changes in existing pigmented lesions (including involution, alteration of color and size, and progression to melanoma) and the onset of new melanocytic lesions—nevi (in 5 patients) and primary melanomas (in 2 patients). Visual examination, dermoscopic evaluation, and reflectance confocal microscopy have been used to document the changes in existing or new melanocytic lesions subsequent to initiating treatment with vermurafenib. Histopathology analysis has shown these lesions to usually be either dysplastic nevi or new primary melanomas. Conclusion: Vemurafenib-treated patients can develop new pigmented lesions (such as nevi) and/or morphological changes in their existing melanocytic lesions (such as involution, increase in size, or alternation of color). In addition, they can develop new primary malignant melanomas that either occur de novo on normal-appearing skin or develop in pre-existing melanocytic lesions. Therefore, total body skin examination should be considered prior to initiating treatment with vemurafenib. Regularly scheduled follow-up skin examinations are also recommended for patients while they are receiving this drug. In addition, for patients who are being treated with vemurafenib, either dermoscopic or photographic or visual modalities should be used to evaluate new or changing pigmented lesions. Also, biopsy for histopathology should be considered for vemurafenib-treated patients who develop new pigmented lesions or whose existing melanocytic lesions have morphological changes in size or color.Vemurafinib is a selective BRAF inhibitor that was approved by the United States Food and Drug Administration (FDA) on August 17, 2011, as a first-line single agent for the treatment of individuals with unresectable or metastatic malignant melanoma whose tumors demonstrated a BRAF V600E mutation as detected by an FDA-approved test.1-4 Clinical trials have demonstrated improved survival in patients with either previously untreated or treated BRAF V600E mutant metastatic malignant melanoma.5,6 The authors describe two men with metastatic malignant melanoma for which their tumor genotype demonstrated BRAF V600E mutation who experience the new onset of nevi after initiating treatment with vemurafenib and discuss changing or new pigmented lesions in patients with metastatic malignant melanoma after starting this molecularly targeted therapy.     

Analysis of mutations in B-RAF, N-RAS, and H-RAS genes in the differential diagnosis of Spitz nevus and spitzoid melanoma

A definite diagnosis cannot be established based on histologic features alone in a large number of Spitz nevi and spitzoid melanomas. In a vast majority of common benign and malignant melanocytic lesions, B-RAF and N-RAS mutations were described, but these were not detected in Spitz nevi. In contrast, H-RAS mutations were frequently encountered in Spitz nevi, but only rarely in melanomas. To date, B-RAF mutation analysis has not been reported in atypical Spitz nevi, and there are only a few reports of it in spitzoid melanomas. We analyzed 96 formalin-fixed, paraffin-embedded spitzoid melanocytic lesions for hotspot mutations in B-RAF, N-RAS, and H-RAS genes to test the assumption whether mutation analysis would assist a more accurate diagnosis of spitzoid melanocytic lesions, which are notoriously difficult to classify. B-RAF or N-RAS mutations were observed in 31 of 36 (86%) spitzoid melanomas, and in 6 of 7 (86%) spitzoid melanoma metastases. In contrast, none of the 14 Spitz nevi and none of the 16 atypical Spitz nevi had mutations in any of the three genes. A B-RAF or N-RAS mutation was found in 8 of 23 (35%) spitzoid lesions suspected for melanoma. H-RAS mutations were detected in 4 of 14 (29%) Spitz nevi, in 3 of 22 (14%) atypical Spitz nevi, in 1 of 15 (7%) spitzoid tumors suspected for melanoma, but in none of the spitzoid melanomas. These results strongly indicate that Spitz nevi and spitzoid melanomas are genetically unrelated entities. Furthermore, we can conclude that mutation analysis may be useful as an additional diagnostic tool to distinguish between benign and malignant spitzoid lesions.     

The Surgical Management of Spitz Nevi

BACKGROUND: The biologic behavior of Spitz nevi and atypical Spitz nevi ranges from completely benign to the rare malignant melanoma. Various recommendations for the surgical approach to these lesions have been proposed. OBJECTIVE: To determine any trend in the surgical management of Spitz nevi and atypical Spitz nevi among a community of dermatologists. METHODS: Retrospective review of the clinical features, surgical management and outcome of 89 patients with the diagnosis of Spitz nevus or atypical Spitz nevus. RESULTS: All biopsy techniques had a high incidence of involved margins: shave (67%), excision (28%), and punch (21%). Of the atypical Spitz nevi with positive margins on biopsy, there was a trend (7/9) toward reexcision with narrow margins (average 2.2 mm). CONCLUSION: The majority of atypical Spitz nevi incompletely removed by biopsy were excised with narrow uncontrolled margins. A stratified surgical approach depending on the clinical and histopathologic features of the Spitz lesion is proposed. More aggressive surgical management of Spitz lesions with atypical features may be warranted. Further studies to determine the biologic potential of these lesions are needed.     

Level of Confidence in Diagnosis: Clinical Examination Versus Dermoscopy Examination

BACKGROUND: Confidence is an important factor in decision making and may influence patient care. OBJECTIVES: To evaluate whether short-training-based dermoscopy increases confidence in the diagnosis of skin lesions. METHODS AND MATERIALS: After a 1-hour course on dermoscopy, 20 pairs of clinical and dermoscopic images of lesions were presented to 19 dermatology residents with little or no dermoscopy experience. After viewing the clinical image, they were asked to assess their confidence in the diagnosis in a seven-point scale, with 1 reflecting that the respondent was 100% confident that the lesion was benign, while number 7 reflected 100% confidence that it was malignant. The same technique was used for dermoscopic images. RESULTS: Ten of the 20 pairs of evaluations showed a significant difference (p<.05). The largest differences were observed in lesions where clinical scores suggested that participants were uncertain about the diagnosis, but tended to decide that the lesion was benign after dermoscopy. Dermoscopy did not improve confidence in the evaluation of dysplastic lesions as well as lesions with obvious clinical diagnoses. CONCLUSIONS: Short-training-based dermoscopy improved confidence in the diagnosis of clinically challenging skin lesions, but the impact was not demonstrable for clinically obvious lesions and dysplastic nevi.     

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.     

Dermoscopic Features of Mucosal Melanosis

BACKGROUND: Melanosis (lentiginosis, labial melanotic macula) is a benign pigmented lesion of mucosa characterized by pigmentation of basal keratinocytes with melanocytic normal or slightly increased in number. Melanosis, particularly when occurring on genitalia, can clinically mimic mucosal melanoma thus creating concern in both the patient and the physician. OBJECTIVE: In this study dermoscopic features from a series of clinically equivocal (n=11) or clinically typical (n=10) mucosal melanosis were analyzed. METHODS: All the women consecutively seen at the Vulva Clinic of the Department of Obstetrics and Gynecology, University of Florence, Italy, from May 1, 2002 to June 30, 2002, were examined. RESULTS: Three major dermoscopic patterns were identified: (1) a "structureless" pattern, predominantly found in clinically equivocal vulvar melanosis, with a blue hue, associated with the presence of melanophages in the upper dermis, present in the majority of these lesions; (2) a "parallel pattern," often found in clinically typical melanotyc macules of the lips and penis; and (3) a "reticular-like" pattern associated with clinically equivocal melanosis occurring at peculiar sites such as the areola (all the three cases occurred at that site) or, rarely, on the lip. CONCLUSIONS: Dermoscopy can play a role in the noninvasive classification of mucosal melanosis. The risk of misclassification with melanoma is probably dependent on dermoscopy pattern shown by the lesion. Prospective studies including early melanomas are needed to establish diagnostic performance of dermoscopy in pigmented lesions of the mucosa.     

Dermoscopic Evolution of a Congenital Combined Nevus in Childhood

Background. A combined nevus most commonly consists of a blue nevus in combination with a Clark or Spitz nevus. Dermoscopically, combined nevus can mimic melanoma owing to the presence of dermoscopic features common to both types of lesions. Benign clinical and dermoscopic changes can occur in nevi over time, especially in children and young adults.
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS.     

Impact of Guidance Provided by a Multispectral Digital Skin Lesion Analysis Device Following Dermoscopy on Decisions to Biopsy Atypical Melanocytic Lesions

Objective: To determine how a multispectral digital skin lesion analysis (MSDSLA) device data affects the biopsy performance of dermatologists and non-dermatologist practitioners following clinical and dermoscopic pigmented lesion evaluation. Design: MSDSLA employs near infrared light to image and analyze pigmented skin lesions. MSDSLA generates a “classifier score” based on morphological disorganization. Using a logistical regression model, 1) a probability of being melanoma and, 2) a probability of being melanoma, atypical melanocytic hyperplasia, or a high grade dysplastic nevus is computed. Participants were shown clinical images of 12 lesions (2 melanomas in situ, 3 invasive melanomas, and 7 low grade DNs). They were asked first if they would biopsy the lesion based on clinical images, again after observing dermoscopy images, and once more when presented with MSDSLA probability information. Setting: National dermoscopy conference. Participants: Sixty-four healthcare providers; 30 dermatologists and 34 non-dermatologist practitioners. Measurements: Sensitivity, specificity, diagnostic accuracy, biopsy rates Results: For the 30 dermatologists, sensitivity was 65 percent after clinical evaluation (C) and 65% post-dermoscopy (D) but improved to 91% after MSDSLA. For the 34 non-dermatologist practitioners, sensitivity improved from 66 percent (C) to 70 percent (D) to 95 percent after MSDSLA. With MSDSLA information, dermatologist specificity increased from 40 percent (D) to 58 percent while non-dermatologist practitioners specificity increased from 34 percent (D) to 55 percent. Diagnostic accuracy of malignant and benign lesions decreased for both groups 55 percent (C) to 51 percent (D) for dermatologists and 54 percent (C) to 49 percent (D) for non-dermatologist practitioners. However, diagnostic accuracy increased to 72 percent for dermatologists and 72 percent for non-dermatologist practitioners with MSDSLA data. Non-melanoma biopsy percentages by dermatologists increased from 53 percent (C) to 60 percent (D), but decreased to 42 percent when provided with MSDSLA data. Similarly, non-dermatologist practitioners’ biopsy percentages of nonmelanomas increased from 55 percent (C) to 66 percent (D) and decreased to 45 percent with MSDSLA. Conclusion: Decisions to biopsy atypical melanocytic lesions were more sensitive and specific when MSDSLA information was provided for both dermatologists and nondermatologist practitioners. Both groups were also less likely to biopsy nonmelanomas after MSDSLA evaluation. The authors’ results suggest providing practitioners with MSDSLA data leads to improved biopsy accuracy decreasing the number of nonessential biopsies for nonmelanocytic lesions even after dermoscopic evaluation.Early detection of melanoma improves survival.1 Suspicious pigmented lesions are typically evaluated by clinical examination and sometimes dermoscopy.2 New technologies may provide additional clinically significant information to augment accurate biopsy decisions.3,4This study was designed to determine how information provided by a multispectral digital skin lesion analysis (MSDSLA) device (MelaFind, MELASciences Inc, Irvington, New York)4,5 affects the biopsy decisions of dermatologists and non-dermatologist practitioners (NDPs) following clinical and dermoscopic pigmented skin lesion evaluation. MSDSLA employs visible and near-infrared light (430-950nm) to image lesions up to 2.5mm below the skin surface. MSDSLA then analyzes pigmented lesions across 10 spectral bands using 75 unique analytical algorithms to determine a “classifier score” based on the degree of morphological disorganization. Validated on a database of 1,632 pigmented lesions,5 MSDSLA also provides the probability of an analyzed lesion being melanoma and melanoma, atypical melanocytic hyper¬plasia (AMH) or a high-grade dysplastic nevus (DN) to the clinician.     

Melanoacanthoma Simulating Pigmented Spitz Nevus: an Unusual Dermoscopy Pitfall

BACKGROUND: The starburst pattern is the dermoscopic hallmark of pigmented Spitz nevus, although it has been rarely observed in melanoma as well. OBJECTIVE: To describe a case of melanoacanthoma simulating pigmented Spitz nevus. MATERIAL AND METHODS: Clinical, dermoscopic, and histopathologic examinations were performed for the occurrence of a 4-mm pigmented skin lesion on the hip of a 38-year-old Caucasian woman. RESULTS: Dermoscopy examination of the lesion disclosed a stereotypical starburst pattern characterized by pigmented streaks symmetrically distributed at the periphery. A preoperative diagnosis of pigmented Spitz nevus was made, and the lesion was excised. However, subsequent histopathologic examination revealed a melanoacanthoma. CONCLUSION: The starburst pattern, although diagnostic for pigmented Spitz nevus, can be rarely observed in other benign or malignant pigmented skin lesions. Accordingly, all lesions in adults exhibiting a starburst pattern or other spitzoid features should be excised for histopathologic evaluation.     

Dermoscopy of Subcorneal Hematoma

BACKGROUND: Subcorneal hematoma is a pigmented skin lesion usually occurring on palms or soles after a trauma or sport activity. Clinically, it may exhibit overlapping features with acral melanoma or acral melanocytic nevi, leading to unnecessary excision of this otherwise harmless skin lesion. OBJECTIVE: The objective was to describe the dermoscopic features in a series of subcorneal hematomas. METHODS: Dermoscopic images of 15 subcorneal hematomas were evaluated for the presence of different colors and dermoscopic structures. RESULTS: In our series, a red-black hue was the most frequent color seen by dermoscopy (40% of the lesions) and a homogeneous pattern of pigmentation was the most frequent dermoscopic structure (53.3%). Remarkably, 40% of the lesions exhibited a parallel-ridge pattern that is usually found in early melanoma of palms and soles. In 46.7% of the lesions, red-black globules were additionally seen at the periphery as satellites disconnected from the lesion's body. Only two lesions showed either parallel-furrow or fibrillar pattern. A scratch test performed in four lesions, allowed complete or partial removal of the pigmentation. CONCLUSION: Dermoscopic features of subcorneal hematomas may be similar to those observed in acral melanocytic lesions. Nevertheless, in most cases the correct diagnosis can be facilitated by the presence of a red-black homogeneous pigmentation, often combined with satellite globules. A positive scratch test may be considered as an additional diagnostic clue.     

Proliferative nodules arising within congenital melanocytic nevi: a histologic, immunohistochemical, and molecular analyses of 43 cases

The histopathologic interpretation of proliferative nodules (PNs) in congenital melanocytic nevi can present significant challenges as some PNs may exhibit atypical features that make the distinction from melanoma difficult. We compared histologic features, Ki-67%, PHH3, and CD117% expression levels by immunohistochemistry in 18 benign and 25 atypical PNs (from 41 patients) with that of background congenital nevi (of these 43 cases), 10 congenital nevi, and 3 dermal melanomas arising in congenital melanocytic lesions. In addition, we evaluated the presence of BRAF, GNAQ, HRAS, KRAS, and NRAS mutations in all groups using the SNaPshot Multiplex System. Follow-up was available on 19 patients (9 benign and 10 atypical PNs) (range, 2 to 20 y; median, 8 y) and all were alive with no evidence of disease. The specific histologic features of atypical PNs, such as sharp demarcation (P<0.001), expansile growth (P<0.001), epidermal effacement (P<0.001), nuclear pleomorphism (P<0.001), and increased mitoses (P<0.001), differed significantly from those of benign PNs. Immunohistochemical results showed that Ki-67% and PHH3 scores, but not CD117% expression, were significantly higher (P<0.05) in atypical PNs. Molecular analyses showed that the PNs and background congenital melanocytic nevi of the giant congenital nevi possess more frequent NRAS mutations and infrequent BRAF mutations when compared with those of the remaining cases. These findings suggest that histologic features and Ki-67 and PHH3 expression levels are the strongest parameters to distinguish between benign versus atypical PNs. The immunohistochemical results suggest that atypical PNs are distinct borderline lesions residing between benign PNs and dermal melanomas. Although numerous mutations are detected in the samples, the diagnostic use of molecular analysis in this regard is limited.     

HMB-45 staining of dysplastic nevi. Support for a spectrum of progression toward melanoma

Dysplastic nevi are melanocytic tumors that occupy intermediate positions in the spectrum of melanocytic proliferations. Although they are invariably cured if completely excised, their biologic potential if left untreated is unknown. We examined a series of such lesions with HMB-45, a melanocyte-specific antibody, in order to explore protein expression within these borderline lesions. HMB-45 has previously been shown to label intraepidermal melanocytes within melanomas and within all nevi. Intradermal melanoma cells also label with HMB-45, but dermal nevus cells within common melanocytic nevi do not normally stain. In contrast, we found mild to moderate staining of nevus cells within the papillary dermis of dysplastic nevi and within residual nevus cells adjacent to malignant melanomas. In the same lesions, we demonstrated strong staining of intraepidermal melanocytes. Thus, dermal nevus cells within dysplastic nevi and within residual nevus cells adjacent to malignant melanomas are expressing low-level amounts of a protein expressed by melanoma cells, but not by dermal nevus cells within wholly benign melanocytic tumors. This lends support to the concept of these lesions as precursor lesions with undetermined biologic potential.     

Regression of Atypical Nevus: An Anecdotal Dermoscopic Observation

BACKGROUND: Clark nevi (atypical melanocytic nevi) can be considered as risk markers and potential precursors of melanoma. The authors report on the morphologic changes of an atypical nevus by dermoscopic follow-up examination over a 7-year period. CASE REPORT: A 43-year-old man had a brown macule on his back, sized 5 mm, with an irregular shape, clinically and dermoscopically diagnosed as an equivocal melanocytic lesion. Dermoscopically during the initial examination, a predominant reticular pattern with peripheral eccentric hyperpigmentation in the lower portion of the lesion could be seen. After 7 months, the area of peripheral eccentric hyperpigmentation had regressed, and after 4.5 years the atypical pigment network had almost disappeared. After 7 years of follow-up, a diffuse area of hypopigmentation and a residual light brown pigmentation were detectable. The histopathologic diagnosis was consistent with an atypical junctional nevus with regression with features of a Clark nevus. CONCLUSION: Based on our observation, even a dermoscopically atypical nevus may undergo regression as documented by long-term dermoscopic follow-up.     

Desmoplastic (sclerotic) nevus: an underrecognized entity that resembles dermatofibroma and desmoplastic melanoma.

Desmoplastic (sclerotic) nevus, a benign melanocytic neoplasm characterized by predominantly spindle-shaped nevus cells within a fibrotic stroma, can be confused with fibrous lesions and other melanocytic proliferations, including desmoplastic melanoma. We compared the histologic and immunohistochemical features of 16 desmoplastic nevi, nine desmoplastic melanomas, four hypopigmented blue nevi, and six dermatofibromas. The similarities between desmoplastic nevi and dermatofibromas included epidermal hyperplasia (12 of 16), presence of keloidal collagen (15 of 16), hypercellularity (16 of 16), and increased numbers of factor XIIIa-positive dendritic cells (12 of 12). The absence of adnexal induction (0 of 16), the rarity of lesions with multinucleated cells (3 of 16) or epidermal hyperpigmentation (2 of 16), and the presence of S-100 immunoreactivity (16 of 16) and melanocytic proliferation (9 of 16) helped differentiate desmoplastic nevi from dermatofibromas. The similarities between desmoplastic nevi and desmoplastic melanomas included the presence of atypical cells (16 of 16) and HMB-45 expression in the superficial portion of the lesions (11 of 16). The infrequent location on the head or neck (1 of 16), the absence of mitotic figures (0 of 16), a significantly lower number of Ki-67-reactive cells, and a decrease in HMB-45 expression in the deep area of the lesions (8 of 11) helped distinguish desmoplastic nevi from desmoplastic melanoma. Desmoplastic nevi had overlapping features with hypopigmented blue nevi, but features tending to favor the latter included a predominance of ovoid nuclei, higher numbers of atypical cells, and homogeneous staining with HMB-45. We conclude that a combination of histologic and immunohistochemical criteria facilitates the reliable diagnosis of desmoplastic nevus from its simulators.     

The Impact of Multispectral Digital Skin Lesion Analysis on German Dermatologist Decisions to Biopsy Atypical Pigmented Lesions with Clinical Characteristics of Melanoma

Objective: To determine the impact of multispectral digital skin lesion analysis on German dermatologist biopsy decisions of atypical pigmented skin lesions. Design: Participants were shown high-resolution clinical images of 12 atypical pigmented skin lesions previously analyzed by multispectral digital skin lesion analysis. Participants were asked if they would biopsy the lesion based on clinical images and high-resolution dermoscopy images and again when subsequently shown multispectral digital skin lesion analysis probability information. Setting/participants: Forty-one dermatologists at a skin cancer conference in Germany in September 2014. Measurements: Sensitivity, specificity, diagnostic accuracy, percent biopsying all melanomas, and overall biopsy rates. Results: Sensitivity for the detection of melanoma following clinical evaluation was 64 percent. After receipt of multispectral digital skin lesion analysis probability information, sensitivity decreased nonsignificantly to 62 percent. Specificity with clinical evaluation was 57 percent and increased to 73 percent using multispectral digital skin lesion analysis. Overall biopsy accuracy increased from 60 percent with clinical evaluation to 68 percent with multispectral digital skin lesion analysis. The percentage of low-grade dysplastic nevi chosen for biopsy decreased from 43 percent after clinical evaluation to 27 percent with multispectral digital skin lesion analysis. Finally, the overall percentage of lesions biopsied decreased from 52 percent with clinical evaluation to 42 percent after multispectral digital skin lesion analysis. Conclusion: Multispectral digital skin lesion analysis can be used reliably to detect melanoma as well as clinical evaluation. Dermatologists can confidently use multispectral digital skin lesion analysis to significantly improve specificity and reduce their overall number of biopsies while increasing overall diagnostic accuracy.The use of technology has dramatically altered the landscape of clinical practice in the last few decades giving the opportunity to enhance cost-effective, quality care. Within the field of dermatology, early diagnosis of melanoma is critical to survival.1 Therefore interventions to enhance timely diagnosis are needed, multispectral digital skin lesion analysis (MSDSLA)2,3 is currently being studied in the United States4 and Germany5 for its use in noninvasively augmenting dermatologist decisions to biopsy suspicious pigmented lesions.MSDSLA employs visible and near-infrared light (430-950nm) to image lesions up to 2.5mm below the skin surface. MSDSLA then analyzes pigmented lesions across 10 spectral bands using 75 unique analytical algorithms to determine a “classifier score” based on the degree of morphological disorganization. Validated on a database of 1,632 pigmented lesions, MSDSLA also provides the probability of an analyzed lesion being melanoma and melanoma, atypical melanocytic hyperplasia (AMH) or a high-grade dysplastic nevus (DN) to the clinician.4The MSDSLA device is available for purchase commercially. Following some training on how to properly acquire an image immersed in isopropyl alcohol, the handheld device takes approximately 30 seconds to image and analyze each pigmented lesion per patient sitting. The additional objective information provided by MSDSLA about a suspicious pigmented lesion is then integrated into a dermatologist’s biopsy decision. MSDSLA is not meant to be followed blindly. For example, if the additional probability information suggests a low probability of melanoma, AMH, or high-grade DN, the final biopsy decision is still up to the experienced dermatologist evaluating the entire clinical picture. The purpose of this study was to determine how physicians’ biopsy decisions are affected by integration of this objective data.     

Digital Polarized Light Dermoscopy of Clinically Nonpigmented Dermal Nevi

BACKGROUND: Hand-held dermoscopy improves the malignant/benign excision ratio for melanocytic lesions. Much has been described about its use in pigmented lesions; however, the use of dermoscopy in clinically nonpigmented lesions is less well studied. Existing studies have used a combination of traditional immersion dermoscopy and polarized light dermoscopy. This is the first study, to our knowledge, to strictly use digital polarized light dermoscopy for the evaluation of clinically nonpigmented, biopsy-proven dermal nevi. OBJECTIVE: The goal of this study was to describe the dermoscopic features of clinically nonpigmented, biopsy-proven dermal nevi using digital polarized light images. METHODS AND MATERIALS: The dermoscopic features of 32 histopathologically confirmed, clinically nonpigmented, dermal nevi were evaluated. Images were obtained with a digital camera equipped with an epiluminescence microscopy attachment (polarized light); no liquid interface was used. RESULTS The most frequent dermoscopic feature of 32 clinically nonpigmented, biopsy-proven dermal nevi was brown pigment (78%) followed by white areas (53%), comma-shaped vessels (50%), hair (47%), hairpin vessels (22%), comedolike openings (22%), and dotted vessels, respectively (19%). CONCLUSIONS: The most common dermoscopic features (using polarized light) of clinically nonpigmented, biopsy-proven dermal nevi are brown pigment, white areas, comma-shaped vessels, and hair.