Immunostain use in the diagnosis of melanomas referred to a tertiary medical center: a 15-year retrospective review (2001-2015)

Quantitative melanoma diagnosis using spectral phasor analysis of hyperspectral imaging from label-free slices

Introduction

Melanoma diagnosis traditionally relies on microscopic examination of hematoxylin and eosin (H&E) slides by dermatopathologists to search for specific architectural and cytological features. Unfortunately, no single molecular marker exists to reliably differentiate melanoma from benign lesions such as nevi. This study explored the potential of autofluorescent molecules within tissues to provide molecular fingerprints indicative of degenerated melanocytes in melanoma.

Methods

Using hyperspectral imaging (HSI) and spectral phasor analysis, we investigated autofluorescence patterns in melanoma compared to intradermal nevi. Using UV excitation and a commercial spectral confocal microscope, we acquired label-free HSI data from the whole-slice samples.

Results

Our findings revealed distinct spectral phasor distributions between melanoma and intradermal nevi, with melanoma displaying a broader phasor phase distribution, signifying a more heterogeneous autofluorescence pattern. Notably, longer wavelengths associated with larger phases correlated with regions identified as melanoma by expert dermatopathologists using H&E staining. Quantitative analysis of phase and modulation histograms within the phasor clusters of five melanomas (with Breslow thicknesses ranging from 0.5 mm to 6 mm) and five intradermal nevi consistently highlighted differences between the two groups. We further demonstrated the potential for the discrimination of several melanocytic lesions using center-of-mass comparisons of phase and modulation variables. Remarkably, modulation versus phase center of mass comparisons revealed strong statistical significance among the groups. Additionally, we identified the molecular endogenous markers responsible for tissue autofluorescence, including collagen, elastin, NADH, FAD, and melanin. In melanoma, autofluorescence is characterized by a higher phase contribution, indicating an increase in FAD and melanin in melanocyte nests. In contrast, NADH, elastin, and collagen dominate the autofluorescence of the nevus.

Discussion

This work underscores the potential of autofluorescence and HSI-phasor analysis as valuable tools for quantifying tissue molecular fingerprints, thereby supporting more effective and quantitative melanoma diagnosis.

Publications on the diagnostic accuracy of dermatopathology tests: A cross-sectional quality analysis

BACKGROUND

Ancillary diagnostic tests are frequent in dermatopathology practice. Publications on their accuracy influence their utilization. The transparency and completeness of these publications are unknown.

METHODS

We performed a cross-sectional study on diagnostic accuracy studies in dermatopathology published between 2020 and 2022 for compliance with Standards for Reporting of Diagnostic Accuracy Studies (STARD) and the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2).

RESULTS

14.67 ± 3.02 STARD items were reported in 62 publications (range, 9.5-23.5 out of the recommended total of 30). More items were reported in high-impact factor journals (16.01 vs. 13.32, p = 0.0002) and journals that endorsed STARD in their author instructions (17.22 vs. 14.11, p = 0.0039). Less than 10% of publications reported quantifiable hypotheses, sample size calculations, flow diagrams, or study registrations. The risk of bias by our analysis of QUADAS-2 criteria was high or uncertain for index test interpretation (36/62, 58%) and patient selection (44/62, 71%).

CONCLUSIONS

Publications on dermatopathology tests are exploratory studies without prespecified hypotheses or study designs. They do not meet the criteria for transparent reporting. We suggest that medical journal leadership should consider updating their instructions with more explicit guidance on recommended manuscript elements.

Insights into Melanoma Clinical Practice: A Perspective for Future Research

BACKGROUND

Early diagnosis is the key to improving outcomes for patients with melanoma, and this requires a standardized histological assessment approach. The objective of this survey was to understand the challenges faced by clinicians when assessing melanoma cases, and to provide a perspective for future studies.

METHODS

Between April 2022 and February 2023, national and international dermatologists, pathologists, general practitioners, and laboratory managers were invited to participate in a six-question online survey. The data from the survey were assessed using descriptive statistics and qualitative responses.

RESULTS

A total of 54 responses were received, with a 51.4% (n = 28) full completion rate. Of the respondents, 96.4% reported ambiguity in their monthly melanoma diagnosis, and 82.1% routinely requested immunohistochemistry (IHC) testing to confirm diagnosis. SOX10 was the most frequently requested marker, and most respondents preferred multiple markers over a single marker. Diagnostic and prognostic tests, as well as therapeutic options and patient management, were all identified as important areas for future research.

CONCLUSIONS

The respondents indicated that the use of multiple IHC markers is essential to facilitate diagnostic accuracy in melanoma assessment. Survey responses indicate there is an urgent need to develop new biomarkers for clinical decision making at multiple critical intervention points.

Mapping knowledge landscapes and emerging trends of the biomarkers in melanoma: a bibliometric analysis from 2004 to 2022

Background

Melanoma is a skin tumor with a high mortality rate, and early diagnosis and effective treatment are the key to reduce its mortality rate. Therefore, more and more attention has been paid for biomarker identification for early diagnosis, prognosis prediction and prognosis evaluation of melanoma. However, there is still a lack of a report that comprehensively and objectively evaluates the research status of melanoma biomarkers. Therefore, this study aims to intuitively analyze the research status and trend of melanoma biomarkers through the methods of bibliometrics and knowledge graph.

Objective

This study uses bibliometrics to analyze research in biomarkers in melanoma, summarize the field's history and current status of research, and predict future research directions.

Method

Articles and Reviews related to melanoma biomarkers were retrieved by using Web of Science core collection subject search. Bibliometric analysis was performed in Excel 365, CiteSpace, VOSviewer and Bibliometrix (R-Tool of R-Studio).

Result

A total of 5584 documents from 2004 to 2022 were included in the bibliometric analysis. The results show that the number of publications and the frequency of citations in this field are increasing year by year, and the frequency of citations has increased rapidly after 2018. The United States is the most productive and influential country in this field, with the largest number of publications and institutions with high citation frequency. Caroline Robert, F. Stephen Hodi, Suzanne L. Topalian and others are authoritative authors in this field, and The New England Journal of Medicine, Journal of Clinical Oncology and Clinical Cancer Research are the most authoritative journals in this field. Biomarkers related to the diagnosis, treatment and prognosis of melanoma are hot topics and cutting-edge hotspots in this field.

Conclusion

For the first time, this study used the bibliometric method to visualize the research in the field of melanoma biomarkers, revealing the trends and frontiers of melanoma biomarkers research, which provides a useful reference for scholars to find key research issues and partners.

The Importance of Immunohistochemistry in the Evaluation of Tumor Depth of Primary Cutaneous Melanoma

Primary cutaneous melanoma (PCM) is the most aggressive skin malignancy, with an increasing incidence and significant mortality. Tumoral invasion, expressed as Breslow thickness, is routinely assessed on hematoxylin and eosin (HE), although this stain may sometimes underestimate the tumoral depth. The aim of this study was to compare the efficiency of the immunohistochemical (IHC) markers S-100, SOX10, Melan-A, and HMB-45 with HE for the evaluation of the Breslow thickness and staging of PCM. This retrospective study included 46 cases of PCM diagnosed between 2015 and 2022; for each case, the Breslow thickness using HE, S-100, SOX10, Melan-A, and HMB-45 was measured and the appropriate T category was recorded. The highest values of the Breslow thickness were observed for S-100. However, S-100, SOX10, and Melan-A provided statistically significant higher values of the Breslow thickness compared to HE, but no difference was noted between HMB-45 and HE. S-100 was most frequently involved in increasing the T category (26.1%), the majority of cases being upstaged from T1a to T1b. The IHC markers S-100, SOX10, and Melan-A contributed to better evaluation of the melanoma invasion, especially in thin melanomas, but their impact on staging and consecutive treatment remains to be confirmed by future studies.

Malignant Melanoma Presenting as Spinal Cord and Pleural Lesions

Primary spinal cord melanoma (PSCM) and primary pleural melanoma (PPM) are extremely rare entities with scarce cases reported in the literature. We present a case of a 54-year-old male diagnosed with possible primary pleural melanoma and primary spinal melanoma, managed with partial surgical resection, postoperative radiotherapy, and chemotherapy consisting of Ipilimumab, nivolumab, and temozolomide. This leads to decreased symptoms and improved quality of life of the patient. In this case report, we review the literature on PSCM and PPM in detail, addressing the pertinent clinical aspects as well as current and upcoming therapeutic options.

Rate of Immunohistochemistry Utilization in the Diagnosis of Cutaneous Melanocytic Lesions

ABSTRACT

Melanocytic lesions represent a large portion of the workload in many laboratories. Although many melanocytic nevi can be confidently diagnosed based on routine hematoxylin and eosin light microscopy, ancillary testing is often warranted. Various immunohistochemical (IHC) stains are routinely used in the diagnosis of melanocytic lesions. Because melanocytic lesions are frequently encountered in skin specimens, the use of IHC is likely to represent a significant area of resource utilization in dermatopathology laboratories. Our study investigates the rate of IHC utilization in the diagnosis of melanocytic lesions in a high-volume, government-funded, not-for-profit laboratory. Of the 1230 cases of melanocytic lesions investigated, including benign as well as malignant entities, 300 cases involved the utilization of IHC. IHC was used in a larger percentage of melanomas than nevi and in a larger percentage of melanoma in situ cases than invasive melanomas. SOX10 was overwhelmingly the most frequently used IHC.

Aberrant Expression of Immunohistochemical Markers in Malignant Melanoma: A Review

Immunohistochemical stains are increasingly used to aid in the diagnosis of malignant melanoma, especially when the differentiation of the tumor is unclear based on examination with hematoxylin and eosin. However, aberrant expression of non-melanocytic markers has been reported in melanomas, which can sometimes be further complicated by the loss of conventional melanocytic markers. This review aims to summarize available data regarding unusual staining patterns in primary and metastatic malignant melanoma. It also raises awareness of the potential pitfalls and highlights the importance of appropriate use and interpretation of broad immunohistochemical markers in the context of clinical and histopathologic findings to facilitate the diagnosis of atypical cases of malignant melanoma.

Utility of histone H3K27me3 and H4K20me as diagnostic indicators of melanoma

Histone posttranslational modifications (PTMs) have been shown to be dysregulated in multiple cancers including melanoma, and as they are abundant and easily detectable, they make ideal biomarkers. The aim of this study was to identify histone PTMs that could be potential biomarkers for melanoma diagnosis. Previously, we utilized mass spectrometry to identify histone PTMs that were dysregulated in matched melanoma cell lines and found two modifications, H3 lysine 27 trimethylation (histone H3K27me3) and H4 lysine 20 monomethylation (histone H4K20me), that were differentially expressed in the more aggressive compared to the less aggressive cell line. In this study, we performed immunohistochemistry on tissue microarrays containing 100 patient tissue spots; 18 benign nevi, 62 primary, and 20 metastatic melanoma tissues. We stained for histone H3K27me3 and histone H4K20me to ascertain whether these histone PTMs could be used to distinguish different stages of melanoma. Loss of histone H4K20me was observed in 66% of malignant patient tissues compared to 14% of benign nevi. A majority (79%) of benign nevi had low histone H3K27me3 staining, while 72% of malignant patient tissues showed either a complete loss or had strong histone H3K27me3 staining. When we analyzed the staining for both marks together, we found that we could identify 71% of the benign nevi and 89% of malignant melanomas. Histone H3K27me3 or histone H4K20me display differential expression patterns that can be used to distinguish benign nevi from melanoma; however, when considered together the diagnostic utility of these PTMs increased significantly. The work presented supports the use of combination immunohistochemistry of histone PTMs to increase accuracy and confidence in the diagnosis of melanoma.

Factors associated with use of immunohistochemical markers in the histopathological diagnosis of cutaneous melanocytic lesions

BACKGROUND

Melanocytic tumors are often challenging and constitute almost one in four skin biopsies. Immunohistochemical (IHC) studies may assist diagnosis; however, indications for their use are not standardized.

METHODS

A test set of 240 skin biopsies of melanocytic tumors was examined by 187 pathologists from 10 US states, interpreting 48 cases in Phase I and either 36 or 48 cases in Phase II. Participant and diagnosis characteristics were compared between those who reported they would have ordered, or who would have not ordered IHC on individual cases. Intraobserver analysis examined consistency in the intent to order when pathologists interpreted the same cases on two occasions.

RESULTS

Of 187 participants interpreting 48 cases each, 21 (11%) did not request IHC tests for any case, 85 (45%) requested testing for 1 to 6 cases, and 81 (43%) requested testing for ≥6 cases. Of 240 cases, 229 had at least one participant requesting testing. Only 2 out of 240 cases had more than 50% of participants requesting testing. Increased utilization of testing was associated with younger age of pathologist, board-certification in dermatopathology, low confidence in diagnosis, and lesions in intermediate MPATH-Dx classes 2 to 4. The median intraobserver concordance for requesting tests among 72 participants interpreting the same 48 cases in Phases I and II was 81% (IQR 73%-90%) and the median Kappa statistic was 0.20 (IQR 0.00, 0.39).

CONCLUSION

Substantial variability exists among pathologists in utilizing IHC.

Immunohistochemical Staining in the Assessment of Melanoma Tumor Thickness

Vertical tumor thickness has great influence in the prognosis and staging of melanoma. The aim of this study was determination of the differences between melanoma tumor thickness in conventional hematoxylin and eosin (H&E) and immunohistochemical techniques. Thirty-six biopsy specimens were included in our study. For each sample, four adjacent tissue sections were stained with H&E, in addition S-100, Melan- A and HMB-45 staining was performed on the next serial sections. The mean thickness of tumor invasion was 2.16, 2.38, 2.22 and 2.29 mm in H&E, S-100, HMB45 and Melan-A sections evaluation, respectively. The mean difference of the Breslow thickness between H&E and S-100 and also, between H&E and Melan-A stained slides were statistically significant (p˂0.05) while no difference was found in the tumor thickness of the H&E and HMB45 staining evaluation (p = 0.278). Greater tumor thickness was observed in 25 lesions (69.4%) with S-100, 20 lesions (55.5%) with Melan-A and 17 (47.2%) lesions in HMB-45 rather than H&E staining. Conclusively, it appears that H&E staining cannot prove the actual size of melanoma invasion in some cases and immunohistochemical examination can be a complementary method in this situations. Of the melanoma associated immunomarkers, the combination of S-100 and Melan-A staining may suffice to measure depth of tumor invasion.

Immunohistochemistry utilization in the diagnosis of melanoma

BACKGROUND

The use of immunohistochemical (IHC) stains in dermatopathology is commonplace; however, little is known regarding utilization trends in melanoma diagnosis. Current Medicare local coverage determinations (LCDs) state that most pigmented lesions, including melanoma, can be diagnosed using H&E alone.

METHODS

Histopathology reports for all biopsy-proven melanomas excised between January 1, 2017 and June 30, 2018, at a single dermatology clinic, were identified with the following parameters abstracted: laboratory/dermatopathologist rendering the diagnosis, whether IHC was performed, type/number of stains utilized, presence/depth of invasion, and melanoma subtype. The association of characteristics with IHC utilization was evaluated using χ² test for categorical variables.

RESULTS

Three hundred and fifty six eligible melanomas were identified. IHC was employed in 228 (64%) of the diagnoses. Invasive melanoma was diagnosed in 199 cases (55.9%) while 157 (44.1%) were identified as melanoma in situ (MIS). Of the 228 that utilized IHC, 117 were performed on invasive melanoma (58.8%) and 111 were performed on MIS (70.7%).

CONCLUSION

Our findings suggest a higher IHC usage for the diagnosis of melanoma than previously reported. Existing LCDs regarding IHC utilization in melanoma do not reflect the current state of practice. Further investigation regarding IHC utilization and the development of appropriate-use criteria for melanoma IHC is necessary.

Risk of second primary cutaneous and noncutaneous melanoma after cutaneous melanoma diagnosis: A population-based study

BACKGROUND

While cutaneous melanomas (CM) account for greater than 90% of all melanomas, noncutaneous melanomas (NCM) are more aggressive and associated with worse outcomes. The shared progenitor cell type among CM and NCM suggests that patients with a history of CM may be at higher risk for subsequent NCM.

OBJECTIVE

To determine whether patients with a history of CM demonstrate an increased risk of second primary cutaneous, ocular, oral, or vaginal/exocervical melanoma compared with the general population.

METHODS

This was a population-based retrospective cohort study using the Surveillance, Epidemiology, and End Results database. We calculated standardized incidence ratios (SIRs) and excess absolute risks of second primary cutaneous, ocular, oral, and vaginal/exocervical melanoma in patients with a history of CM.

RESULTS

Patients with prior CM (n = 169,841) were more likely than the general population to develop a second primary CM (SIR, 8.17; 95% confidence interval [CI], 8.01-8.33), ocular melanoma (SIR, 1.99; 95% CI, 1.54-2.53), oral melanoma (SIR, 6.87; 95% CI, 2.23-16.04), and vaginal/exocervical melanoma (SIR, 10.17; 95% CI, 4.65-19.30).

LIMITATIONS

This study is limited by possible under-reporting of CM in cancer registries.

CONCLUSION

In caring for patients with a history of CM, physicians should be vigilant not only about risk of recurrence but also about second primary CM and NCM.

Current state of melanoma diagnosis and treatment

Melanoma is the deadliest form of skin cancer. In the early stages, melanoma can be treated successfully with surgery alone and survival rates are high, but after metastasis survival rates drop significantly. Therefore, early and correct diagnosis is key for ensuring patients have the best possible prognosis. Melanoma misdiagnosis accounts for more pathology and dermatology malpractice claims than any cancer other than breast cancer, as an early misdiagnosis can significantly reduce a patient's chances of survival. As far as treatment for metastatic melanoma goes, there have been several new drugs developed over the last 10 years that have greatly improved the prognosis of patients with metastatic melanoma, however, a majority of patients do not show a lasting response to these treatments. Thus, new biomarkers and drug targets are needed to improve the accuracy of melanoma diagnosis and treatment. This article will discuss the major advancements of melanoma diagnosis and treatment from antiquity to the present day.

Guidelines of care for the management of primary cutaneous melanoma

The incidence of primary cutaneous melanoma continues to increase each year. Melanoma accounts for the majority of skin cancer-related deaths, but treatment is usually curative following early detection of disease. In this American Academy of Dermatology clinical practice guideline, updated treatment recommendations are provided for patients with primary cutaneous melanoma (American Joint Committee on Cancer stages 0-IIC and pathologic stage III by virtue of a positive sentinel lymph node biopsy). Biopsy techniques for a lesion that is clinically suggestive of melanoma are reviewed, as are recommendations for the histopathologic interpretation of cutaneous melanoma. The use of laboratory, molecular, and imaging tests is examined in the initial work-up of patients with newly diagnosed melanoma and for follow-up of asymptomatic patients. With regard to treatment of primary cutaneous melanoma, recommendations for surgical margins and the concepts of staged excision (including Mohs micrographic surgery) and nonsurgical treatments for melanoma in situ, lentigo maligna type (including topical imiquimod and radiation therapy), are updated. The role of sentinel lymph node biopsy as a staging technique for cutaneous melanoma is described, with recommendations for its use in clinical practice. Finally, current data regarding pregnancy and melanoma, genetic testing for familial melanoma, and management of dermatologic toxicities related to novel targeted agents and immunotherapies for patients with advanced disease are summarized.

Morphologic and Immunohistochemical Characteristics of Anorectal Melanoma

Anorectal melanoma is a rare aggressive disease. Due to its rarity and considerable histologic and immunohistochemical variabilities, misdiagnosis as lymphoma, carcinoma, sarcoma, and/or gastrointestinal stromal tumor is not uncommon, particularly in amelanotic cases. We reviewed histologic features and immunohistochemical stains of 19 anorectal melanoma cases. Histopathologic features were evaluated including junctional activity, melanin pigment, and morphologic features. Immunohistochemical stains were performed using Sox10, S100 protein, HMB-45, melan-A, CD56, and cytokeratins. Epithelioid histopathologic morphology was observed in 63.2% of the cases followed by 47.4% of the cases with spindle-cell, 26.3% with lymphoma-like, and 26.3% with pleomorphic morphologies. Junctional melanocytic activity was seen in almost half of the cases. Melanin pigment was absent (amelanotic) in nearly 40% of the cases. Immunohistochemically, diffuse positive expression of Sox10, S100 protein, melan-A, and HMB-45 was seen in 100%, 40%, 53.3%, and 38.5% of the cases, respectively. Cytokeratins were negative and CD56 was positive in 2 cases. These findings indicate that anorectal melanomas often show one or combined histolopathologic features without presence of melanin pigment and absence of junctional melanocytic activity. Anorectal melanoma should be kept in mind in the differential diagnosis of malignant neoplasms of anorectal region with epithelioid, spindle-cell, lymphoma-like, and pleomorphic morphologies. Sox10 immunohistochemistry stain can be used as a first-line screening tool to avoid extensive or unnecessary workups and/or potential misdiagnosis.