Relationship of Histopathologic Parameters and Gene Expression Profiling in Malignant Melanoma.

BACKGROUND: Histopathologic characteristics (HC) are a mainstay in melanoma prognosis; gene expression profiling (GEP) has emerged as a potential additional independent value. OBJECTIVE: To elucidate HC predictive of groups obtained via GEP of malignant melanoma. METHODS: A retrospective study analyzing HC of 265 melanomas submitted for GEP over the course of 8 years. GEP was conducted as a part of regular clinicopathologic workup through Castle Biosciences Decision Dx®. RESULTS: Of the 265 cases, the major HC found to have an association with reported gene expression profiles were melanoma histology subtype, depth of invasion, and presence of ulcer. LIMITATIONS: This study is limited by its cross-sectional nature. Causation and long-term related outcomes of the use of GEP versus American Joint Committee on Cancer histopathologic staging cannot be ascertained by this design. CONCLUSIONS: An association, but no definitive prediction, exists between histopathologic categories of depth of invasion, melanoma subtype, and presence or absence of ulcer and gene expression profiles. GEP adds valuable data to the evaluation of malignant melanomas that cannot be definitively predicted by conventional models. The findings add to needed groundwork for comparison of traditional markers and molecular genotyping and begins to build a robust predictive model for better outcomes in patients with malignant melanoma.

A Case Presentation of Three Polypoid Melanomas With Divergent Features.

Polypoid melanoma, a subtype of nodular melanoma, is classified as the most aggressive and deadly form of cutaneous melanoma. Its rapid vertical growth phase and a wide array of divergent features make clinical diagnosis extremely difficult. This report includes three cases of polypoid melanoma that were all originally thought to be other benign lesions or non-melanoma cancer. These cases feature the variability of the clinical presentation of polypoid melanomas while emphasizing the importance of an annual skin examination, complete lesion biopsies, and working with experienced dermatopathologists for the correct diagnosis and prompt treatment of these cancers. By sharing these cases and general information on polypoid melanoma, we aim to spread awareness of this rarer subtype of melanoma and highlight the importance of having a broad differential list when presented with suspicious lesions.

Cutaneous Secondary Syphilis Resembling Non-Melanoma Skin Cancer.

The cutaneous manifestations of secondary syphilis can vary significantly between patients, leading to a more difficult or delayed diagnosis. Here we present an instructive case of secondary syphilis in a 45-year-old, HIV-positive male patient. He presented with a solitary, crusted anterior neck nodule without concomitant systemic symptoms. Together, history and physical exam were concerning for non-melanoma skin cancer. Histopathologic evaluation of the lesion revealed an extensive infiltrate of plasma cells at the dermoepidermal junction, and immunohistochemical staining revealed numerous Treponema pallidum microorganisms. Physicians must keep syphilis in the differential diagnosis when evaluating atypical nodular lesions resembling non-melanoma skin cancer for the purpose of initiating appropriate antibiotic treatment and preventing future infectious complications.

Concordance of somatic mutation profiles (BRAF,NRAS, and TERT) and tumoral PD-L1 in matched primary cutaneous and metastatic melanoma samples.

Despite the efficacy of BRAF-targeted and PD-L1-related immune therapies in tackling metastatic melanoma, a significant number of patients exhibit resistance. Given this, the objective of the current study was to ascertain concordance of somatic mutations in BRAF/NRAS/TERT and immunohistochemical PD-L1 and CD8 in matched primary cutaneous and metastatic melanoma. A total of 43 archival paired samples with sufficient material for genetic and immunohistochemical analyses met the criteria for inclusion in the study. Immunohistochemistry was performed for PD-L1 and CD8 and direct-DNA Sanger sequencing for BRAF/NRAS/TERT promoter mutational analyses. Agreement between paired samples was assessed using Cohen κ. Poor concordance among primary and corresponding metastases was noted in BRAF (9/42 cases discordant, κ = 0.49; 95% confidence interval [CI], 0.21-0.77; P = .0013), TERT promoter mutations (13/41 cases discordant, κ = 0.33; 95% CI, 0.04-0.62; P = .033), tumoral PD-L1 immunoexpression (9/43 cases discordant, κ = 0.39; 95% CI, 0.07-0.72; P = .0099), and immunoexpression of CD8+ T lymphocytes (12/43 cases discordant, κ = 0.44; 95% CI, 0.19-0.69; P = .002). Although NRAS1 and NRAS2 were highly concordant (42/43 and 39/43 cases, respectively), discordant NRAS2 mutational status was associated with a median time to metastasis of 90 versus 455 days for pairs with concordant status (P = .07). Although limited by sample size, our findings suggest that consideration be given to mutational analysis of metastatic tissue rather than the primary to guide BRAF-targeted therapy and question the roles of TERT promoter mutations and PD-L1 as predictive biomarkers in malignant melanoma.

Eccrine-Centric Melanocytic Nevus.

Benign melanocytic neoplasms present with a diverse array of well-known histopathologic patterns. It is imperative to recognize the benign patterns to render accurate diagnoses. We describe here an interesting and hitherto not described low-power architectural pattern of a benign melanocytic lesion: eccrine-centric melanocytic nevus. The patient was a 50-year-old African American woman who noticed a new mole on her foot that began as a dark speck but quickly grew larger. The lesion was excised to exclude the possibility of melanoma. Upon review of the specimen, the lesion was noted to demonstrate a distinctive pattern consistent with a melanocytic nevus of possible congenital onset. Remarkably, the ducts of eccrine glands were increased in density and the nests of melanocytes were found solely in a peri-eccrine distribution without melanocytes in any other locations (ie, interstitial, perifollicular). Additionally, all melanocytes in the nevus were rather heavily pigmented. Although this pattern demonstrated no atypical features that would cause one to consider it malignant to the trained eye, this presentation could implicate a metastatic disease (well-delineated nests in the dermis without concomitant interstitial component) and it is important to recognize.

Two Cases of Lepromatous Leprosy from Exposure to Armadillos in Florida.

The first patient was a 41-year-old white man who was referred to the dermatology clinic with a 2-year history of numerous erythematous, hypoesthetic, poorly demarcated papules and plaques present on the trunk, buttocks, and bilateral upper and lower extremities (Figures 1 and 2). The lesions had initially begun as localized erythematous plaques on the right flank, and were diagnosed and treated as cellulitis and allergic contact dermatitis by primary care on separate occasions, with no resolution and continued gradual but persistent spread.

Feasibility study in teledermatopathology: An examination of the histopathologic features of mycosis fungoides and spongiotic dermatitis.

BACKGROUND: Digital pathology offers numerous advantages, allowing remote information sharing using whole slide imaging (WSI) to digitize an entire glass slide (GS) at high resolution, creating a digital slide (DS). METHODS: In this study, we examine the concordance in diagnoses made on 40 digital slides (DSs) vs traditional GSs in differentiating between spongiotic dermatitis (SD) and patch/plaque-stage mycosis fungoides (MF). RESULTS: Greater interobserver concordance rate in final diagnosis of SD vs MF was observed with the utilization of DS (86.7%) compared with the utilization of GS (80%). Intraobserver concordance rate between the diagnoses rendered by a particular dermatopathologist on GS and DS was 86.7%. For all histopathological criteria, a correlation in the magnitudes of interobserver vs intraobserver discordances suggests that discordance between glass vs digital evaluation of these criteria may be largely expected subjective read variation independent of the media. Discordance in identification of histopathological features did not have a statistically significant link to discordance in diagnosis for 7 out of the 8 features. CONCLUSIONS: The similarity between interobserver and intraobserver discordances suggests that WSI does not introduce additional barriers or variability to accurately identify histopathologic feature and to discriminate between MF and SD beyond interobserver variability.

Comparing whole slide digital images versus traditional glass slides in the detection of common microscopic features seen in dermatitis.

BACKGROUND: The quality and limitations of digital slides are not fully known. We aimed to estimate intrapathologist discrepancy in detecting specific microscopic features on glass slides and digital slides created by scanning at ×20. METHODS: Hematoxylin and eosin and periodic acid-Schiff glass slides were digitized using the Mirax Scan (Carl Zeiss Inc., Germany). Six pathologists assessed 50-71 digital slides. We recorded objective magnification, total time, and detection of the following: Mast cells; eosinophils; plasma cells; pigmented macrophages; melanin in the epidermis; fungal bodies; neutrophils; civatte bodies; parakeratosis; and sebocytes. This process was repeated using the corresponding glass slides after 3 weeks. The diagnosis was not required. RESULTS: The mean time to assess digital slides was 176.77 s and 137.61 s for glass slides (P < 0.001, 99% confidence interval [CI]). The mean objective magnification used to detect features using digital slides was 18.28 and 14.07 for glass slides (P < 0.001, 99.99% CI). Parakeratosis, civatte bodies, pigmented macrophages, melanin in the epidermis, mast cells, eosinophils, plasma cells, and neutrophils, were identified at lower objectives on glass slides (P = 0.023-0.001, 95% CI). Average intraobserver concordance ranged from κ = 0.30 to κ = 0.78. Features with poor to fair average concordance were: Melanin in the epidermis (κ = 0.15-0.58); plasma cells (κ = 0.15-0.49); and neutrophils (κ = 0.12-0.48). Features with moderate average intrapathologist concordance were: parakeratosis (κ = 0.21-0.61); civatte bodies (κ = 0.21-0.71); pigment-laden macrophages (κ = 0.34-0.66); mast cells (κ = 0.29-0.78); and eosinophils (κ = 0.31-0.79). The average intrapathologist concordance was good for sebocytes (κ = 0.51-1.00) and fungal bodies (κ = 0.47-0.76). CONCLUSIONS: Telepathology using digital slides scanned at ×20 is sufficient for detection of histopathologic features routinely encountered in dermatitis cases, though less efficient than glass slides.

Role of histological findings and pathologic diagnosis for detection of human papillomavirus infection in men.

Early HPV infection in males is difficult to detect clinically and pathologically. This study assessed histopathology in diagnosing male genital HPV. External genital lesions (n = 352) were biopsied, diagnosed by a dermatopathologist, and HPV genotyped. A subset (n = 167) was diagnosed independently by a second dermatopathologist and also re-evaluated in detail, tabulating the presence of a set of histopathologic characteristics related to HPV infection. Cases that received discrepant diagnoses or HPV-related diagnoses were evaluated by a third dermatopathologist (n = 163). Across dermatopathologists, three-way concordance was fair (k = 0.30). Pairwise concordance for condyloma was fair to good (k = 0.30-0.67) and poor to moderate for penile intraepithelial neoplasia (k = -0.05 to 0.42). Diagnoses were 44-47% sensitive and 65-72% specific for HPV 6/11-containing lesions, and 20-37% sensitive and 98-99% specific for HPV 16/18. Presence of HPV 6/11 was 75-79% sensitive and 35% specific for predicting pathologic diagnosis of condyloma. For diagnosis of penile intraepithelial neoplasia, HPV 16/18 was 95-96% specific but only 40-64% sensitive. Rounded papillomatosis, hypergranulosis, and dilated vessels were significantly (P < 0.05) associated with HPV 6/11. Dysplasia was significantly (P = 0.001) associated with HPV 16/18. Dermatopathologists' diagnoses of early male genital HPV-related lesions appear discordant with low sensitivity, while genotyping may overestimate clinically significant HPV-related disease. Rounded papillomatosis, hypergranulosis, and dilated vessels may help establish diagnosis of early condyloma.

Glomus-like bodies within a neurofibroma: a novel neoplasm arising in neurofibromatosis type 1 or a coincidence?

Neurofibromatosis type 1 is a relatively common genetic disorder with variable phenotypes. Tumors with features of both glomus tumors and neurofibromas are exceedingly rare in literature. Herein, we report a not yet described neoplasm with features of both a glomangioma/glomus tumor and a neurofibroma arising in a patient with segmental neurofibromatosis. Our case report supports the theory of a common lineage/ancestor cell between neurofibromas and glomus tumors and adds it to the spectrum of neoplasms that may arise in the setting of Von Recklinghausen's disease.

Adenoid cystic carcinoma of the base of the tongue metastasizing to the scalp.

Adenoid cystic carcinoma is a rare neoplasm that originates from secretory glands, most commonly from the salivary glands. We present a 76 year-old white man with a history of adenoid cystic carcinoma from the base of the tongue diagnosed 15 years prior to the development of the metastatic lesion on his mid-posterior scalp. The present case represents the second reported instance of an extracutaneous adenoid cystic carcinoma metastasizing to the scalp. Differentiating between a primary cutaneous adenoid cystic carcinoma and an extracutaneous adenoid cystic carcinoma metastasizing to cutaneous structures is crucial in determining prognosis and management.

Analysis of tumor mitotic rate in thin metastatic melanomas compared with thin melanomas without metastasis using both the hematoxylin and eosin and anti-phosphohistone 3 IHC stain.

Studies have suggested that elevated tumor mitotic rate (MR) is linked to overall survival in thin melanoma. Recently, promising data regarding anti-phosphohistone 3 (pHH3) immunohistochemistry and its ability to aid in calculation of MR have emerged. The authors retrospectively analyzed original biopsies from 13 thin melanomas with positive sentinel node (SN) status and 16 thin melanomas with negative SN status. Both anti-pHH3 immunohistochemistry and the hematoxylin and eosin (H&E) stain were used to evaluate MR by 2 dermatopathologists blinded to SN status using the "hot spot" method. Intraclass coefficient values were attained to measure interobserver concordance and reliability of the pHH3 stain. By generating a receiver operating characteristic curve and analyzing the overall area under the curve, pHH3 was found to have good interobserver reliability. The relationship between MR and SN involvement was also evaluated, but this correlation was not statistically significant.

Hyperspectral imaging of melanocytic lesions.

Hyperspectral imaging (HSI) allows the identification of objects through the analysis of their unique spectral signatures. Although first developed many years ago for use in terrestrial remote sensing, this technology has more recently been studied for application in the medical field. With preliminary data favoring a role for HSI in distinguishing normal and lesional skin tissues, we sought to investigate the potential use of HSI as a diagnostic aid in the classification of atypical Spitzoid neoplasms, a group of lesions that often leave dermatopathologists bewildered. One hundred and two hematoxylin and eosin-stained tissue samples were divided into 1 of 4 diagnostic categories (Spitz nevus, Spitz nevus with unusual features, atypical Spitzoid neoplasm, and Spitzoid malignant melanoma) and 1 of 2 control groups (benign melanocytic nevus and malignant melanoma). A region of interest was selected from the dermal component of each sample, thereby maximizing the examination of melanocytes. Tissue samples were examined at ×400 magnification using a spectroscopy system interfaced with a light microscope. The absorbance patterns of wavelengths from 385 to 880 nm were measured and then analyzed within and among groups. All tissue groups demonstrated 3 common absorbance spectra at 496, 533, and 838 nm. Each sample group contained at least one absorption point that was unique to that group. The Spitzoid malignant melanoma category had the highest number of total and unique absorption points for any sample group. The data were then clustered into 12 representative spectral classes. Although each of the sample groups contained all 12 spectral vectors, they did so in differing proportions. These preliminary results reveal differences in the spectral signatures of the Spitzoid lesions examined in this study. Further investigation into a role for HSI in classifying atypical Spitzoid neoplasms is encouraged.

Cutaneous human papillomavirus types detected on the surface of male external genital lesions: a case series within the HPV Infection in Men Study.

BACKGROUND: Cutaneous human papillomaviruses (HPVs) may be associated with cutaneous epithelial lesions and non-melanoma skin cancers. No study has systematically evaluated the presence of genus beta [ß]-HPV in male genital skin or external genital lesions (EGLs) OBJECTIVES: To examine cutaneous ß-HPV types detected on the surface of EGLs in men and describe their presence prior to EGL development. STUDY DESIGN: A retrospective case series was conducted among 69 men with pathologically confirmed EGLs (n=72) who participated in the HPV Infection in Men Study. Archived exfoliated cells collected from the surface of each EGL and normal genital skin specimens 6-12 months preceding EGL development were tested for ß-HPV DNA using a type-specific multiplex genotyping assay. RESULTS: ß-HPV DNA was detected on 61.1% of all EGLs, with types 38 (16.7%), 5 (15.3%), and 12 (12.5%) most commonly identified. HPV prevalence differed across pathological diagnoses, with the largest number of ß-HPV types detected on condylomas. Most ß-HPV types were detected on normal genital skin prior to EGL development, though the prevalence was lower on EGLs compared to preceding normal genital skin. CONCLUSIONS: EGLs and the normal genital skin of men harbor a large number of ß-HPV types; however, it appears that ß-HPVs are unrelated to EGL development in men. Despite evidence to support a causal role in skin carcinogenesis at UVR-exposed sites, cutaneous HPV appears unlikely to cause disease at the UVR-unexposed genitals.

OpenSlide: A vendor-neutral software foundation for digital pathology.

Although widely touted as a replacement for glass slides and microscopes in pathology, digital slides present major challenges in data storage, transmission, processing and interoperability. Since no universal data format is in widespread use for these images today, each vendor defines its own proprietary data formats, analysis tools, viewers and software libraries. This creates issues not only for pathologists, but also for interoperability. In this paper, we present the design and implementation of OpenSlide, a vendor-neutral C library for reading and manipulating digital slides of diverse vendor formats. The library is extensible and easily interfaced to various programming languages. An application written to the OpenSlide interface can transparently handle multiple vendor formats. OpenSlide is in use today by many academic and industrial organizations world-wide, including many research sites in the United States that are funded by the National Institutes of Health.

Pediatric melanoma: analysis of an international registry.

BACKGROUND: The management of pediatric melanoma (PM) has largely been extrapolated from adult data. However, the behavior of PM appears to differ from its adult counterparts. Therefore, an international PM registry was created and analyzed. METHODS: Twelve institutions contributed deidentified clinicopathologic and outcome data for patients diagnosed with PM from 1953 through 2008. RESULTS: Overall survival (OS) data were reported for 365 patients with invasive PM who had adequate follow-up data. The mean age of the patients was 16 years (range 1 year-21 years). The 10-year OS rate, 80.6%, tended to vary by patient age: 100% for those aged birth to 10 years, 69.7% for those aged > 10 years to 15 years, and 79.5% for those aged > 15 years to 20 years (P = .147). Patients with melanomas measuring ≤ 1 mm had a favorable prognosis (10-year OS rate of 97%), whereas survival was lower but similar for patients with melanomas measuring > 1 mm to 2 mm, > 2 mm to 4 mm, and > 4 mm (70%, 78%, and 80%, respectively; P = .0077). Ulceration and lymph node metastasis were found to be correlated with worse survival (P = .022 and P = .017, respectively). The 10-year OS rate was 94.1% for patients with American Joint Committee on Cancer stage I disease, 79.6% for those with stage II disease, and 77.1% for patients with stage III disease (P < .001). CONCLUSIONS: Tumor thickness, ulceration, lymph node status, and stage were found to be significant predictors of survival in patients with PM, similar to adult melanoma. There is a trend toward increased survival in children aged ≤ 10 years versus adolescents aged > 10 years. Further analyses are needed to probe for potential biological and behavioral differences in pediatric versus adult melanoma.

Composite hemangioendothelioma and its classification as a low-grade malignancy.

Hemangioendotheliomas are vascular neoplasms occupying a spectrum of biological potential ranging from benign to low-grade malignancy. Composite hemangioendothelioma (CH) is one of the less commonly encountered variants exhibiting a mixture of elements of other hemangioendothelioma subtypes, such as epithelioid, retiform, and spindle cell. Some authors have identified areas histopathologically equivalent to angiosarcoma within CH, raising the question of the true nature of this neoplasm. Although CH recurs locally, there are only 3 reported cases which metastasized. To date, 26 cases (including the present case) have been described in the literature. Herein, we describe a unique case of CH arising in the background of previous radiation therapy and long-standing lymphedema (classically associated with the development of angiosarcoma-Stewart-Treves syndrome) that harbored higher grade areas but behaved as a low-grade malignant neoplasm. This, in conjunction with the many reported cases of CH-harboring angiosarcoma-like areas, and the occasional association with a history of lymphedema, raises the question of whether this variant of hemangioendothelioma may actually be an angiosarcoma that behaves prognostically better than the conventional type. After careful study of the natural disease progression of the current case and review of the literature, we discuss justification for the continued classification of CH as a low-grade malignancy.

Automated detection of heuristics and biases among pathologists in a computer-based system.

The purpose of this study is threefold: (1) to develop an automated, computer-based method to detect heuristics and biases as pathologists examine virtual slide cases, (2) to measure the frequency and distribution of heuristics and errors across three levels of training, and (3) to examine relationships of heuristics to biases, and biases to diagnostic errors. The authors conducted the study using a computer-based system to view and diagnose virtual slide cases. The software recorded participant responses throughout the diagnostic process, and automatically classified participant actions based on definitions of eight common heuristics and/or biases. The authors measured frequency of heuristic use and bias across three levels of training. Biases studied were detected at varying frequencies, with availability and search satisficing observed most frequently. There were few significant differences by level of training. For representativeness and anchoring, the heuristic was used appropriately as often or more often than it was used in biased judgment. Approximately half of the diagnostic errors were associated with one or more biases. We conclude that heuristic use and biases were observed among physicians at all levels of training using the virtual slide system, although their frequencies varied. The system can be employed to detect heuristic use and to test methods for decreasing diagnostic errors resulting from cognitive biases.

Discrepancies in dermatopathology diagnoses: the role of second review policies and dermatopathology fellowship training.

BACKGROUND: Expert consultation and institutional policies mandating second review of pathologic diagnoses in the course of referral have been advocated to optimize patient care. OBJECTIVE: We sought to investigate the rate of diagnostic discrepancies between pathologists with and without dermatopathology fellowship training. METHODS: All available outside pathology reports were reviewed for material sent to the University of Pittsburgh Medical Center Dermatopathology Unit during 1 year. The outside diagnosis was compared with the diagnosis rendered by the referral dermatopathology service. Cases were assigned into 1 of 4 categories: melanocytic neoplasm, nonmelanocytic neoplasm, inflammatory, and other. For each case, the outside pathologist's level of dermatopathology training was noted. Any change in diagnosis resulting in significant alteration in therapy or prognosis, as dictated by the accepted standard of care, was considered a major discrepancy. RESULTS: A total of 405 cases were reviewed. In 51 cases (13%), no preliminary diagnosis was rendered at the outside facility. The referral diagnosis differed from the outside diagnosis in 226 cases (56%), and major discrepancies were identified in 91 cases (22%). Of these 91 cases, 84 were received from outside pathologists who were not dermatopathology trained and 7 were received from pathologists with dermatopathology training. The 91 cases with major discrepancies were categorized as: 36 nonmelanocytic neoplasms (40%), 30 inflammatory (33%), 23 melanocytic neoplasms (25%), and 2 other (2%). LIMITATIONS: This was a retrospective study limited to 2 consultant dermatopathologists at an academic referral center, which typically receives and reviews select cases. CONCLUSION: Dermatopathology fellowship training is associated with a substantial decrease in major diagnostic discrepancies. Pathologists without dermatopathology fellowship training tend to successfully identify those cases for which expert consultation is most useful.