Clinical relevance of detection of lymphovascular invasion in primary melanoma using endothelial markers D2-40 and CD34

A comparison of myeloid-derived suppressor cell populations in patients with ulcerated vs non-ulcerated melanoma receiving immune checkpoint blockade

Myeloid-derived suppressor cells (MDSCs) are expanded in cancer patients, have an intrinsic immunosuppressive function, and thus may play a role in resistance to immunotherapy. Ulceration of the melanoma primary is associated with more aggressive disease and is an independent prognostic factor for melanoma-specific survival. However, the underlying factors contributing to this more aggressive phenotype are not completely understood. The current study aims to correlate changes in circulating MDSC during immunotherapy in patients with ulcerated vs non-ulcerated melanoma primary tumors. Longitudinal changes in levels of circulating MDSCs were analyzed via flow cytometry in melanoma patients receiving immune checkpoint inhibitors (ICIs) and stratified by ulceration status. Following the initiation of therapy, the percentage of total MDSCs increased significantly in patients with both ulcerated ( P  = 0.003) and non-ulcerated ( P  < 0.001) tumors. When MDSCs were stratified by subset, the proportion of granulocytic MDSC (PMN-MDSC) decreased in patients with non-ulcerated tumors ( P  = 0.023), while the proportion remained stable in patients with ulcerated tumors ( P  = 0.121). The reduction in the proportion PMN-MDSC in non-ulcerated patients coincided with a statistically significant increase in the proportion of CD14 + /CD15 + MDSC ( P  = 0.008), resulting in a greater proportion of CD14 + /CD15 + MDSC in non-ulcerated patients as compared to ulcerated melanoma patients following two infusions of ICIs (27.3 ± 19.2% vs 16.1 ± 19.2%; P  = 0.008). The trajectories of the MDSC populations described here provide insight into the altered tumor microenvironment in ulcerated melanoma and highlight key changes in a cell population that could contribute to immunotherapy resistance.

Deep Learning Predicts Lymphovascular Invasion Status in Muscle Invasive Bladder Cancer Histopathology

BACKGROUND

Lymphovascular invasion (LVI) is linked to poor prognosis in patients with muscle-invasive bladder cancer (MIBC). Accurately identifying the LVI status in MIBC patients is crucial for effective risk stratification and precision treatment. We aim to develop a deep learning model to identify the LVI status in whole-slide images (WSIs) of MIBC patients.

PATIENTS AND METHODS

A cohort from The Cancer Genome Atlas (TCGA) database was used to train a deep learning model, slide-based lymphovascular invasion predictor (SBLVIP), based on multiple-instance learning. This model was externally validated using the Renmin Hospital of Wuhan University (RHWU) and People's Hospital of Hanchuan City (PHHC) cohorts. Kaplan-Meier curves, along with univariate and multivariate Cox models, were employed to evaluate the association between the LVI status predicted by SBLVIP and the survival outcomes of MIBC patients.

RESULTS

In the TCGA cohort, the SBLVIP model achieved an average accuracy of 0.804 [95% confidence interval (CI) 0.712-0.895] and an area under the receiver operating characteristic curve (AUC) of 0.77 (95% CI 0.63-0.84) in the training set. In the internal validation set, the model's average accuracy and AUC were 0.774 (95% CI, 0.701-0.846) and 0.76 (95% CI, 0.60-0.83), respectively. In the RHWU cohort, the SBLVIP model achieved an average accuracy of 0.807 (95% CI 0.734-0.880) and an AUC of 0.74 (95% CI 0.55-0.83). In the PHHC cohort, SBLVIP demonstrated an average accuracy of 0.821 (95% CI 0.737-0.909) and an AUC of 0.74 (95% CI 0.58-0.89). Moreover, the LVI status predicted by SBLVIP showed significant independent prognostic value (P = 1 × 10-6).

CONCLUSIONS

We developed a deep learning model named SBLVIP to predict the LVI status in routine WSIs of MIBC patients.

Clinical, dermatoscopic, histological and molecular predictive factors of distant melanoma metastasis: A systematic review and meta-analysis

BACKGROUND

Melanoma metastasis to distant sites is associated with diminished survival rates and poor prognosis. Except of Breslow thickness and ulceration that are currently used in melanoma staging, the investigation of additional clinicopathological, dermatoscopic and molecular factors that could predict tumors with aggressive biologic behavior is of paramount importance.

METHODS

A literature search was conducted in PubMed, Scopus, Cochrane databases and gray literature until November 2023. Observational studies (including cohorts and case-control studies) were included and clinical and histopathological factors of primary cutaneous melanomas, along with dermatoscopic and molecular predictors of distant metastasis (DM) and distant metastasis-free survival (DMFS) were assessed. Random - effect models were preferred, the results were presented as Hazard Ratios (HRs) with 95 %Confidence Intervals (CIs) and the I2 index quantified heterogeneity. Subgroup analysis according to AJCC stage and sensitivity analysis were also conducted.

RESULTS

One hundred forty-three and 101 studies were included in the qualitive and quantitative synthesis, respectively. Regarding clinical factors, males, compared to females, and head and neck location, compared to trunk, demonstrated higher risk for DM [n=36, HR 1.49, 95%CI 1.36 - 1.63, I2 33% and n=21, HR 1.24, 95 %CI 1.01 - 1.52, I2 62 %]. Both factors had similar effects on DMFS. Breslow thickness and ulceration were significant predictors or DM. Additional factors that posed an increased risk for DM were nodular (n=15, HR 2.51, 95 %CI 1.83 - 3.43, I2 56 %) and lentigo maligna subtypes (n=12, HR 1.87, 95 %CI 1.27 - 2.75, I2 0 %), compared to superficial spreading subtype, lymphovascular invasion (n=9, HR 2.05, 95 %CI 1.18 - 3.58, I2 78 %), SLN positivity and BRAF+ mutational status. In contrast, regression was a negative predictor of DM (n=15, HR 0.59, 95 %CI 0.44 - 0.79, I2 68 %). Two studies focused on dermatoscopic factors and found that low pigmentation and the presence of blue-white veil might predict DM development. The results of subgroup analysis for stage I-II patients were essentially similar and sensitivity analysis did not reveal significant alterations, despite the moderate or high heterogeneity in some categories.

CONCLUSIONS

Clinical and histological characteristics of the tumor along with dermatoscopic features and molecular parameters hold significant prognostic information and could be incorporated into models to predict melanomas with high metastatic potential.

Can angiotropism and lymphovascular invasion refine the current cutaneous melanoma staging system?

BACKGROUND

Several prognostic factors for primary cutaneous melanoma (PCM) have been identified, and these predict metastasis and survival, to a certain extent. We sought to determine the frequency of angiotropism (AT) and lymphovascular invasion (LVI) in PCM and the relationship between AT, LVI, and other clinicopathological parameters and patient's prognosis.

METHODS

This study included 538 cases of PCM diagnosed between 2003 and 2016. It comprised 246 females and 292 males whose clinicopathological variables were evaluated with respect to LVI and AT using univariate and multivariate analyses. Overall survival (OS) was assessed by Kaplan-Meier (KM) analysis and Cox regression multivariate analysis.

RESULTS

AT occurred more frequently than LVI. Ulceration, mitotic rate, and Breslow thickness were found to be highly associated with both LVI and AT (p < 0.01). All LVI+ cases had AT, with a significant positive correlation (p < 0.01). Both AT and LVI predicted lymph node (LN) metastasis (odds ratio [OR] = 1.47, 1.12, respectively). Multivariate analysis showed LN metastasis, Breslow thickness, LVI, and AT as predictors of OS. LVI and AT independently predicted adverse OS by Cox regression analysis (hazard ratio [HR] = 1.66, 1.49, respectively) and with KM survival analysis.

CONCLUSION

AT is a marker for angiotropic extravascular migratory tumor spread (angiotropic EVMM), and LVI is a marker for intra-lymphovascular tumor spread. Both predict poor prognosis. Given its ease of detection, AT could be adopted as a histologpathological feature in the routine assessment of primary cutaneous malignant melanoma cases.

Prognostic and predictive biomarkers in melanoma

Biomarkers help to inform the clinical management of patients with melanoma. For patients with clinically localised primary melanoma, biomarkers can help to predict post-surgical outcome (including via the use of risk prediction tools), better select patients for sentinel lymph node biopsy, and tailor catch-all follow-up protocols to the individual. Systemic drug treatments, including immune checkpoint inhibitor (ICI) therapies and BRAF-targeted therapies, have radically improved the prognosis of metastatic (stage III and IV) cutaneous melanoma patients, and also shown benefit in the earlier setting of stage IIB/C primary melanoma. Unfortunately, a response is far from guaranteed. Here, we review clinically relevant, established, and emerging, prognostic, and predictive pathological biomarkers that refine clinical decision-making in primary and metastatic melanoma patients. Gene expression profile assays and nomograms are emerging tools for prognostication and sentinel lymph node risk prediction in primary melanoma patients. Biomarkers incorporated into clinical practice guidelines include BRAF V600 mutations for the use of targeted therapies in metastatic cutaneous melanoma, and the HLA-A∗02:01 allele for the use of a bispecific fusion protein in metastatic uveal melanoma. Several predictive biomarkers have been proposed for ICI therapies but have not been incorporated into Australian clinical practice guidelines. Further research, validation, and assessment of clinical utility is required before more prognostic and predictive biomarkers are fluidly integrated into routine care.

Lymphatic expression of the proliferation marker Ki67 is linked to sentinel node positivity, recurrence and mortality in primary cutaneous melanoma

Lymphangiogenesis is a precursor to lymphovascular invasion, and may therefore signal a higher risk of metastasis and mortality in primary cutaneous melanoma. This retrospective longitudinal study aimed to evaluate whether emergent lymphangiogenesis, as measured through co-expression of endothelial proteins with the proliferation marker Ki67, was associated with poorer prognosis in a cohort of patients with single primary cutaneous melanoma. We screened all patients with a single locally invasive primary cutaneous melanoma who received sentinel lymph node biopsy at a tertiary dermatology centre in Brisbane, Australia between 1994 and 2007. Primary melanoma sections were stained via Opal multiplex immunofluorescence, and categorized according to the presence of Ki67 within either CD31+ or D2-40+ endothelial cells. Multivariate Cox regression modelling was used to evaluate associations between endothelial Ki67 positivity and clinical outcomes, with adjustment for age, sex, Breslow depth, ulceration, and anatomical location. Overall, 264 patients were available for analysis, with a median follow-up duration of 7.1 years. The presence of D2-40+ /Ki67+ co-expression was associated with greater melanoma-specific mortality (adjusted hazard ratio [HR]: 2.03; 95% confidence interval [CI]: 1.33-3.10; p = 0.001) and recurrence (adjusted HR: 1.70; 95% CI: 1.33-3.10; p = 0.001) relative to absence. CD31+ /Ki67+ co-expression was not prognostic in this cohort. Lymphatic proliferation, as measured through D2-40+ /Ki67+ co-expression, predicted greater melanoma-specific mortality and recurrence in this cohort of primary cutaneous melanoma.

Inflammatory breast cancer biomarkers and biology

Inflammatory breast cancer (IBC) is a unique breast cancer with a highly virulent course and low 5- and 10-year survival rates. Even though it only accounts for 1-5% of breast cancers it is estimated to account for 10% of breast cancer deaths annually in the United States. The accuracy of diagnosis and classification of this unique cancer is a major concern within the medical community. Early molecular and biological studies incidentally included IBC samples with other conventional breast cancers and were not informative as to the unique nature of the disease. Subsequent molecular studies that focused specifically on IBC demonstrated that IBC has a unique biology different from other forms of breast cancer. Additionally, a handful of unique signature genes that are hallmarks of IBC have also been suggested. Further understanding of IBC biology can help with diagnosis and treatment of the disease. The current article reviews the history and highlights of IBC studies.

Tissue Biomarkers Predicting Lymph Node Status in Cutaneous Melanoma

Cutaneous melanoma is a severe neoplasm that shows early invasiveness of the lymph nodes draining the primary site, with increased risk of distant metastases and recurrence. The tissue biomarker identification could be a new frontier to predict the risk of early lymph node invasiveness, especially in cases considered by current guidelines to be at low risk of lymph node involvement and not requiring evaluation of the sentinel lymph node (SLN). For this reason, we present a narrative review of the literature, seeking to provide an overview of current tissue biomarkers, particularly vascular endothelium growth factors (VEGF), Tetraspanin CD9, lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), D2-40, and gene expression profile test (31-GEP). Among these, 31-GEP seems to be able to provide a distinction between low or high risk for positive SLN classes. VEGF receptor-3 and CD9 expression may be independent predictors of positive SLN. Lastly, LYVE-1 and D2-40 allow an easier assessment of lymph vascular invasion, which can be considered a good predictor of SLN status. In conclusion, biomarkers to assess the lymph node status of cutaneous melanoma patients may play an important role in those cases where the clinician is in doubt whether or not to perform SLN biopsy.

Ulcerated Cutaneous Melanoma: A Review of the Clinical, Histologic, and Molecular Features Associated with a Clinically Aggressive Histologic Phenotype

The presence of ulceration in melanoma is associated with poor clinical outcomes and is the third most powerful predictor of survival in the AJCC Melanoma Staging System after tumor thickness and mitotic activity. The aggressive biological behavior associated with ulceration has been hypothesized to be the result of an intrinsic biological attribute that favors dissemination and presents locally with the loss of epidermal integrity. Among the features of ulcerated melanoma, many show promise as potential prognostic tools, markers of differential immunogenicity and indicators of oncogenic drivers of invasion and metastasis. The incidence of ulcerated melanoma is greater in males, increases with age and with systemic inflammatory risk factors (diabetes, smoking, low vitamin D, elevated body mass index). Patients with ulcerated primary tumors seem to exclusively benefit from adjuvant interferon (IFN) therapy, which is likely the consequence of an altered tumor microenvironment. When ulceration is present, there is a higher density of macrophages and dendritic cells and enhanced expression of pro-inflammatory cytokines, such as IL-6. There is also an increased expression of proteins involved in tumor antigen presentation in ulcerated melanomas. Histologically, vascular density, vasculogenic mimicry and angiotropism are all significantly correlated with ulceration in melanoma. The presence of ulceration is associated with reduced protein expression of E-cadherin and PTEN and elevated levels of N-cadherin and the matrix metalloproteinases. Differential microRNA expression also holds promise as a potential prognostic biomarker of malignancy and disease spread within the setting of ulceration. However, the molecular and cellular differences associated with the ulcerated state are complex and further study will aid in determining how these differences can be harnessed to improve care for patients with melanoma.

Hematoxylin and eosin or double stain for CD34/SOX10: Which is better for the detection of lymphovascular invasion in cutaneous melanoma?

BACKGROUND

Lymphovascular invasion (LVI) is considered an unfavorable prognostic factor in cutaneous melanoma (CM). However, its detection by hematoxylin and eosin (H&E) is challenging, with discordant data about its association with clinical-pathological features and no previous studies investigating the inter- (IrOA) and intra-observer (IaOA) agreement. Herein, we tested H&E and double staining (DS) for CD34/SOX10 to detect the LVI in a cohort of 92 CMs, evaluating the IrOA, the IaOA, and the association with the other clinical-pathological features.

METHODS

Five authors independently evaluated 92 consecutive and retrospectively enrolled cases of CMs. We assessed the IrOA (Fleiss's Kappa/FK and intraclass correlation coefficient/ICC) and the IaOA (Cohen's Kappa/CK) with both H&E and CD34/SOX10. Furthermore, we compared the LVI assessment with the two stains and analyzed the association with other clinical-pathological features [χ2 tests for dichotomous and categorical data; Student t-test (normal distribution) and Mann-Whitney U-test (non-normal distribution) for continuous data].

RESULTS

The IrOA was almost identical with H&E (FK=0.446; ICC=0.805) and CD34/SOX10 (FK=0.454; ICC=0.810); by contrast, the IaOA was higher with H&E for one pathologist (CK: 0.809) and with CD34/SOX10 for the other one (CK: 0.563). Applying previously defined criteria, LVI was detected in 10 (9.2%) and 11 (10.1%) cases with H&E and CD34/SOX10, respectively (p = 1.000). Both H&E and CD34/SOX10 were significantly associated with vertical growth phase (H&E, p: 0.014; CD34/SOX10, p: 0.010), mitosis ≥ 1/mm2 (H&E, p: 0.000; CD34/SOX10, p: 0.004), pT (H&E, p: 0.000; CD34/SOX10, p: 0.001), Breslow thickness (H&E, p: 0.000; CD34/SOX10, p: 0.001), and lymph node and/or distant metastasis (H&E, p: 0.005; CD34/SOX10, p: 0.000); only H&E was associated with ulceration (p: 0.002) and distant metastasis (p: 0.000), conversely, only CD34/SOX10 was associated with lymph node metastasis (p: 0.003).

CONCLUSIONS

CD34/SOX10 does not improve the IrOA and the IaOA of the LVI assessment in CM; furthermore, H&E and CD34/SOX10 show a similar profile of association with the other unfavorable clinical-pathological features of CM. As result, CD34/SOX10 could be a redundant diagnostic tool if applied for the prognostic characterization of not-selected CM in a routine diagnostic scenario.

Recurrence Status, Perineural Invasion, and Hypothyroidism Are Associated With Lymph Node Metastasis in Cutaneous Squamous Cell Carcinoma: A Case-Control Study

BACKGROUND

Lymph node metastasis is a critical prognostic indicator for mortality in patients with cutaneous squamous cell carcinoma (SCC).

OBJECTIVE

To identify and characterize key risk factors for SCC lymph node metastasis.

METHODS

This was a multi-institutional, case-control study of 65 cutaneous SCCs with known lymph node metastasis matched with 195 cutaneous SCCs without lymph node metastasis (3:1 matching). The cases and controls were matched by anatomic location, age, and sex. Odds ratios (ORs) and their 95% confidence intervals (CIs) were generated to determine the association between specific risk factors and lymph node metastasis in a multivariate analysis.

RESULTS

Recurrent tumors (p < .001), perineural invasion (p < .001), lymphovascular invasion (p = .002), size of 2 cm or greater (p = .008), and hypothyroidism (p = .03) were significantly more common in the lymph node metastasis cohort. Recurrence (OR 6.3, 95% CI 2.6-15.3), perineural invasion (OR 4.5, 95% CI 1.7-11.8), and hypothyroidism (OR 2.7, 95% CI 1.04-7.0) remained significant on performing a multivariate analysis.

CONCLUSION

Lymph node metastasis in SCC is associated with recurrence, perineural invasion, lymphovascular invasion, size of 2 cm or greater, and hypothyroidism. Clinical consideration of these findings within the context of current staging systems may help improve patient outcomes.

Optimizing Detection of Lymphatic Invasion in Primary Cutaneous Melanoma With the Use of D2-40 and a Paired Melanocytic Marker

ABSTRACT

Dual immunohistochemical (IHC) staining with D2-40 and S100 improves detection of lymphatic invasion (LI) in primary cutaneous melanoma. However, limited data exist evaluating this technique using other melanocytic markers, and thus, the optimal marker for detection of LI is unestablished. To address this knowledge gap, a case-control study was performed comparing melanoma specimens from 22 patients with known lymphatic spread (LS) with a control group of 11 patients without LS. Specimens underwent dual IHC staining with D2-40 and MART-1, SOX-10, and S100 to evaluate for LI. Receiver operating characteristic analysis was used to estimate each stain's accuracy for detection of LI. The LS group was more likely to be ≥65 years (P = 0.04), have a tumor thickness of ≥1 mm (P < 0.01), and have ulcerated tumors (P = 0.02). Detection of LI with D2-40/MART-1 significantly correlated with LS (P = 0.03), and the D2-40/MART-1 stain was most accurate for LI based on receiver operating characteristic curve analysis (area under the curve [AUC] 0.705) in comparison with D2-40/SOX-10 (AUC 0.575) and D2-40/S100 (AUC 0.633). These findings suggest that MART-1 may be the optimal melanocytic marker to combine with D2-40 for detection of LI in melanoma. Further studies are needed to determine the utility of routinely performing these stains for histopathologic analysis of melanoma.

Prognostic Significance of Lymphovascular Invasion Detected by D2-40 in Low-Risk Stage II Colon Cancer

Background

Lymphovascular invasion (LVI) is included in the criteria of high-risk stage II colon cancer. However, there are limitations to detecting LVI by routine hematoxylin and eosin (H&E) staining. Alternatively, immunohistochemistry (IHC) for the lymphatic endothelial marker D2-40 may help detect LVI, but its prognostic significance remains unknown. This study aimed to evaluate the prognostic significance of LVI, detected by IHC for D2-40, in low-risk stage II colon cancer. 

Materials and Methods

A total of 69 patients with low-risk stage II colon cancer were tested for D2-40 to assess LVI. Then, the relationships between IHC-detected LVI and clinical outcomes, including disease-free survival (DFS) and overall survival (OS), were analyzed using both univariate and multivariate analyses. 

Results

IHC for D2-40 revealed that 24 out of the 69 cases (34.78%) had LVI-positive tumors. IHC-detected LVI was significantly associated with adverse clinical outcomes on univariate analysis, i.e., both reduced DFS (P = 0.002) and OS (P = 0.0163). In multivariate analysis, controlling for age, IHC-detected LVI remained a significant predictor of reduced DFS with a hazard ratio (HR) of 3.37 and a 95% confidence interval (CI) of 1.39-8.15 (P = 0.007) and OS (HR, 5.66; 95% CI, 1.02-31.51; P = 0.048).

Conclusions

Our results demonstrated that IHC analysis for D2-40 enhanced LVI detection in patients with low-risk stage II colon cancer and that cases with a missed diagnosis of LVI by routine H&E staining had adverse clinical outcomes, that is, reduced DFS and OS.  

Multiple combinations of melanocytic and vascular endothelial markers enhance the detection rate of lymphovascular invasion in cutaneous melanoma

BACKGROUND

Lymphovascular invasion (LVI) is believed to be the mechanism by which melanoma cells can disseminate to regional lymph nodes and distant sites and may be predictive of adverse outcome. Lymphovascular invasion often difficult to detect on hematoxylin-eosin (HE) stained sections, are readily identified with dual immunohistochemistry (IHC) for melanocytic and vascular markers.

METHODS

A total of 100 primary cutaneous malignant melanoma cases that had a Breslow thickness of 1-4 mm and lacked LVI by conventional HE assessment were included. We compared the LVI detection rates of double staining for CD31/S100 and CD34/S100, and D2-40/S100, and examined the association of LVI with clinical outcomes.

RESULTS

The dual immunohistochemical positivity for CD31/S100, CD34/S100, and D2-40/S100 were 40(40%), 17(17%) and 35(35%), respectively. On multivariate analysis, LVI was an independent predictor of SLN status. Multivariate analysis revealed that LVI and male gender were independent risk factors for overall survival.

CONCLUSIONS

The recognition of LVI is improved by dual IHC and predicts SLN metastasis. The detection of LVI using dual IHC, especially by a combination of CD31/S100 and D2-40/S100 is a useful step that inclusion should be recommended in basic evaluation parameters for cutaneous melanoma.

Dissecting the Lymphatic System to Predict Melanoma Metastasis

Melanoma is the most lethal form of skin cancer in the United States. Current American Joint Committee on Cancer (AJCC) staging uses Breslow depth and ulceration as the two primary tumor factors that predict metastatic risk in cutaneous melanoma. Early disease stages are generally associated with high survival rates. However, in some cases, patients with thin melanomas develop advanced disease, suggesting other factors may contribute to the metastatic potential of an individual patient’s melanoma. This review focuses on the role of the lymphatic system in the metastasis of cutaneous melanoma, from recent discoveries in mechanisms of lymphangiogenesis to elements of the lymphatic system that ultimately may aid clinicians in determining which patients are at highest risk. Ultimately, this review highlights the need to integrate pathological, morphological, and molecular characteristics of lymphatics into a “biomarker” for metastatic potential.

Lymphatic invasion in acral and non-acral melanoma: a comparative, clinicoprognostic study of primary cutaneous melanoma according to tumour site

There have been limited studies comparing the clinical significance of lymphatic invasion in melanoma according to tumour site. The objective of this study was to evaluate the impact of lymphatic invasion on the clinicoprognostic features of acral and non-acral melanoma. Clinical and histopathological features and survival outcomes of 532 patients with acral melanoma or non-acral melanoma in the database of the Asan Medical Center, Korea, were retrospectively evaluated according to the presence of lymphatic invasion. Lymphatic invasion was significantly more common in acral melanoma than non-acral melanoma. In acral melanoma, lymphatic invasion was significantly associated with a higher frequency of lymph node involvement and advanced stages, but not associated with Breslow thickness or visceral dissemination. By contrast, lymphatic invasion in non-acral melanoma was significantly associated with a higher rate of visceral involvement, deeper Breslow thickness, as well as a higher rate of lymph node involvement and advanced stages. When acral melanoma and non-acral melanoma both with lymphatic invasion were compared, Breslow thickness was significantly shallower and vertical growth phase was significantly less common in acral melanoma. Meanwhile, visceral involvement was significantly more frequent in non-acral melanoma than acral melanoma. In conclusion, lymphatic invasion was more common in acral melanoma than non-acral melanoma and occurred in acral melanoma cases with relatively thin Breslow thickness, suggesting acral melanoma is lymphotropic.

Pathology-based Biomarkers Useful for Clinical Decisions in Melanoma

The dramatic recent advances in therapy of melanoma require a more personalized and precise diagnostic approach to aid in clinical decisions. Tissue-based biomarkers in pathology have diagnostic, prognostic and predictive relevance. Herein we review the most commonly used pathology-based biomarkers in melanoma. Most of these biomarkers are evaluated through immunohistochemistry (IHC) or fluorescent in situ hybridization (FISH) performed on formalin fixed paraffin embedded tissue (FFPE), and are widely available in clinical pathology laboratories. We describe the utility of MART1/Ki67, p16, PRAME, markers of lymphovascular invasion (D2-40, CD31, D2-40/MITF, CD31/SOX-10), BRAF V600E, NRAS, KIT, BAP1, ALK, NTRK, PD-L1, TERT, PTEN, iNOS, and MMR proteins (MLH1, MSH2, MSH6, PMS2) in the evaluation of melanoma specimens. Correct interpretation and awareness of the significance of these biomarkers is crucial for pathologists, dermatologists, and oncologists who take care of melanoma patients.

Integrin β4 Is an Effective and Efficient Marker in Synchronously Highlighting Lymphatic and Blood Vascular Invasion, and Perineural Aggression in Malignancy

Lymphovascular invasion (LVI) and perineural invasion (PNI) are 2 important pathologic parameters and need to be accurately assessed in multiple malignancies. Integrin β4, a member of the integrin family, has been reported to be positively expressed in vascular endothelia, peripheral nerves, and a collection of epithelia. However, little is known about the effectiveness of β4 immunostaining on the recognition of LVI and PNI. Herein, we explored the applicability of β4 immunostaining in stomach, thyroid, and breast cancers. Parallel immunostaining of D2-40, CD34, and S-100 was performed as controls for lymphatic endothelia, vascular endothelia, and neural fibers, respectively. The results demonstrated that β4 concurrently stained the lymphatic and vascular endothelia, and the peripheral nerves. Both LVI and PNI were clearly and accurately outlined by β4 immunostaining. β4 was also expressed in the majority of tumor cells, enabling recognition of LVI and PNI encroached by small tumor clusters. In contrast to D2-40 and CD34, β4 staining was not observed in stromal cells, and therefore it facilitated differentiation between the shrinkage cleft and LVI. According to our results, β4 staining strikingly increased the diagnostic accuracy and interobserver concordance for LVI and PNI compared with hematoxylin and eosin staining alone. Finally, the applicability of β4 was confirmed in 9 other types of malignancies, including cancers of the colon, prostate, esophagus, lung, kidney, uterus, tongue, bladder, and liver. Collectively, β4 is a reliable marker for synchronous detection and diagnosis of LVI and PNI.

Risk Factors for Lymphatic and Hematogenous Dissemination in Patients With Stages I to II Cutaneous Melanoma

Importance

The lymphatic and the hematogenous pathways have been proposed for disease progression in cutaneous melanoma, but association with recurrence has not been studied separately to date.

Objective

To identify the risk factors associated with lymphatic and hematogenous metastasis.

Design, Setting, and Participants

This retrospective cohort study included 1177 patients with malignant melanoma treated at Instituto Valenciano de Oncología, València, Spain. Data were retrieved from the melanoma database from January 1, 2000, through December 31, 2015, and analyzed from June 1 to 30, 2018.

Exposure

Malignant melanoma at stages I to II.

Main Outcomes and Measures

Analyses of survival free of lymphatic and hematogenous metastasis were performed using Kaplan-Meier curves and Cox proportional hazards regression.

Results

For the 1177 patients included in the study analysis (51.1% women; median age at diagnosis, 55 years [interquartile range, 42-68 years), median follow-up was 75 months (interquartile range, 33-121 months); 108 (9.2%) developed lymphatic metastasis, and 108 (9.2%) developed hematogenous metastasis. In the multivariate analysis, being older than 55 years (hazard ratio [HR], 1.9; 95% CI, 1.2-3.1), tumor in the head/neck (HR, 1.7; 95% CI, 1.0-2.9) and acral locations (HR, 2.4; 95% CI, 1.3-4.5), greater Breslow thickness (HR for >4.00 mm, 5.4; 95% CI, 2.4-12.4), and presence of vascular invasion (HR, 3.2; 95% CI, 0.9-10.6) were associated with lymphatic spreading. Hematogenous metastasis was associated with greater Breslow thickness (HR for >4.00 mm, 10.4; 95% CI, 3.6-29.7), the absence of regression (HR, 0.1; 95% CI, 0.0-1.0), TERT promoter mutations (HR, 2.9; 95% CI, 1.5-5.7), and BRAF mutations (HR, 1.9; 95% CI, 1.1-3.6).

Conclusions and Relevance

Risk factors associated with lymphatic and hematogenous metastasis differ. Follow-up and adjuvant treatment strategies may therefore need to be adapted to individual clinical, histopathologic, and molecular characteristics.

Pathology of Melanoma

Melanoma is an aggressive malignancy arising from melanocytes in the skin and rarely in extracutaneous sites. The understanding of pathology of melanoma has evolved over the years, with the initial classifications based on the clinical and microscopic features to the current use of immunohistochemistry and genetic sequencing. The depth of invasion and lymph node metastasis are still the most important prognostic features of melanoma. Other important prognostic features include ulceration, lymphovascular invasion, mitosis, and tumor-infiltrating lymphocytes. This article reviews the pathology of melanoma and its precursor lesions, along with the recent advances in pathologic diagnosis of melanoma.

A Practical Approach to the Diagnosis of Melanocytic Lesions

CONTEXT.—

Melanocytic lesions are common in routine surgical pathology. Although the majority of these lesions can be confidently diagnosed using well-established morphologic criteria, there is a significant subset of lesions that can be diagnostically difficult. These can be a source of anxiety for patients, clinicians, and pathologists, and the potential consequences of a missed diagnosis of melanoma are serious.

OBJECTIVE.—

To provide a practical approach to the diagnosis of melanocytic lesions, including classic problem areas as well as suggestions for common challenges and appropriate incorporation of ancillary molecular techniques.

DATA SOURCES.—

Literature search using PubMed and Google Scholar, incorporating numerous search terms relevant to the particular section, combined with contemporaneous texts and lessons from personal experience.

CONCLUSIONS.—

Although a subset of melanocytic lesions can be diagnostically challenging, the combination of a methodical approach to histologic assessment, knowledge of potential diagnostic pitfalls, opinions from trusted colleagues, and judicious use of ancillary techniques can help the pathologist navigate this difficult area.

Regional Lymph Node Metastases in Groin Sarcomas: A Diagnostic and Therapeutic Challenge

INTRODUCTION

The evaluation of lymph nodes and the role of groin dissection for groin sarcomas has been controversial where there have not been previous studies or guidelines published. In this study, we aim to first formulate a clinical approach in the evaluation of regional lymph nodal metastases. Second, we aim to also evaluate the role of regional lymphadenectomy in the setting of pathologically involved regional lymph nodes for groin sarcomas.

MATERIALS AND METHODS

In total, 43 consecutive patients with groin sarcomas underwent treatment at the National Cancer Centre Singapore between 2002 and 2015. Univariate comparisons were performed using the log-rank test. A Cox multivariate analysis was performed for disease-specific survival to identify independent prognostic factors.

RESULTS

The median disease-free survival was 18 months (range, 1 to 180 mo). The median overall survival (OS) was 28 months (range, 3 to 180 mo). In total, 28 patients underwent a groin dissection. Of the 28 patients who underwent groin dissections, 15 had negative lymph node involvement, 7 had positive lymph node involvement and 6 had lymphovascular invasion.On univariate analysis, grade (P=0.047) and clinical and/or radiological involvement (P=0.039) were significant for regional lymph nodal metastases.The 5-year OS for patients with positive lymph nodes was 31%.

CONCLUSIONS

Our study suggests that the evaluation of lymph nodes via groin dissections in groin sarcomas in the Asian population should be based primarily on clinical and radiologic evidence. Regional lymph node dissection seems to confer OS benefit in patients with these high-risk tumors and can improve local control of disease.

Emerging Biomarkers in Cutaneous Melanoma

Earlier identification of aggressive melanoma remains a goal in the field of melanoma research. With new targeted and immune therapies that have revolutionized the care of patients with melanoma, the ability to predict progression and monitor or predict response to therapy has become the new focus of research into biomarkers in melanoma. In this review, promising biomarkers are highlighted. These biomarkers have been used to diagnose melanoma as well as predict progression to advanced disease and response to therapy. The biomarkers take various forms, including protein expression at the level of tissue, genetic mutations of cancer cells, and detection of circulating DNA. First, a brief description is provided about the conventional tissue markers used to stage melanoma, including tumor depth. Next, protein biomarkers, which provide both diagnostic and prognostic information, are described. This is followed by a discussion of important genetic mutations, microRNA, and epigenetic modifications that can provide therapeutic and prognostic material. Finally, emerging serologic biomarkers are reviewed, including circulating melanoma cells and exosomes. Overall the goal is to identify biomarkers that aid in the earlier identification and improved treatment of aggressive melanoma.

Compared With Elastin Stains, h-Caldesmon and Desmin Offer Superior Detection of Vessel Invasion in Gastric, Pancreatic, and Colorectal Adenocarcinomas

BACKGROUND

The presence of vessel invasion is considered indicative of a poor prognosis in many malignant tumors. We aimed to compare the sensitivity of elastin stains (van Gieson's and orcein methods) with 2 smooth muscle markers (h-caldesmon and desmin) in gastric, pancreatic, and colorectal adenocarcinoma specimens.

MATERIALS AND METHODS

We used 27 (29.3%) gastric, 35 (38.0%) pancreatic, and 30 (32.6%) colorectal resection specimens. We applied a provisional classification of vessel invasion patterns: type A, a focus with a nearby artery unaccompanied by a vein; type T, a focus at the invasive front without an unaccompanied artery; and type X, foci that only appeared by any of the 4 stains used.

RESULTS

There were 369 foci. The smooth muscle markers were more sensitive than the elastin stains, and h-caldesmon more sensitive than desmin, in all types. Among the 139 type A foci, 33 (23.7%) were positive by desmin and h-caldesmon, whereas the elastin stains were not ( P = .001). h-Caldesmon was the only positive marker in 11 (7.9%; P = .011). Among the 78 type T foci, 21 (26.9%) were positive by desmin and h-caldesmon, when both elastin stains were negative ( P = .000). In 16 (20.5%) foci, h-caldesmon was the only positive marker ( P = .002). Among 152 type X foci, 91 (59.9%) were positive by all markers, 26 (17.1%) by both desmin and h-caldesmon, and 9 (5.9%) by only the 2 elastin stains ( P = .001).

CONCLUSION

We recommend these stains for suspect foci in gastric, pancreatic, and colorectal adenocarcinoma specimens. They might highlight both predictable and unpredictable foci.

Utility of ERG Immunohistochemistry for Evaluation of Lymphovascular Invasion in Testicular Germ Cell Tumors: A Retrospective Pilot Study

Lymphovascular invasion (LVI) of testicular germ cell tumors (GCT) is an important stage-determining variable in the evaluation of radical orchiectomy specimens. ERG endothelial cell expression, as detected by immunohistochemistry (IHC), robustly highlights lymphovascular spaces, and thus, we sought to assess the utility of ERG IHC for evaluation of GCT LVI. Hematoxylin and eosin (H&E) slides from a retrospective cohort of 25 GCT radical orchiectomy specimens (emanating from a parent cohort of 159 radical orchiectomy GCT cases identified between 2003 and 2013) were reviewed, and sections with foci of positive or equivocal LVI were identified. ERG IHC was performed on sections off the surface of corresponding paraffin tissue blocks. All foci were then rescored as positive, equivocal, or negative for LVI based on ERG endothelial cell expression. Twenty-three and 13 foci were positive or equivocal for LVI by H&E staining, respectively. Among the H&E positive LVI foci, 20 (87%) were ERG IHC positive, whereas of the H&E equivocal LVI foci, 5 (38%) were ERG IHC positive, 3 (23%) were ERG IHC negative, and 2 (15%) were ERG IHC equivocal; all other foci were lost for evaluation. Overall, ERG IHC helped resolve the LVI status of 61% of foci deemed equivocal for LVI by H&E staining only. Although ERG IHC is useful in confirming definitive LVI status in a subset of GCT cases, the overall clinical impact of ERG IHC is limited for H&E equivocal LVI foci in this specific retrospective patient cohort. Overall, in carefully selected clinical scenarios, these data suggest a supportive role for ERG IHC in evaluation of GCT LVI in radical orchiectomy specimens.

Lymphatic invasion predicts sentinel lymph node metastasis and adverse outcome in primary cutaneous melanoma

BACKGROUND

Sentinel lymph node (SLN) metastasis is a powerful predictor of survival in primary cutaneous melanoma. Lymphatic invasion (LI) may correlate with increased risk of SLN metastasis. Intralymphatic metastases, often difficult to detect on hematoxylin and eosin (H&E) stained sections, are readily identified with dual immunohistochemistry for melanocytic and lymphatic markers.

METHODS

We used dual S100/D240 immunohistochemistry to detect LI in 125 melanomas from patients who underwent SLN biopsy and correlated LI with melanoma staging parameters and disease status.

RESULTS

Dual immunohistochemistry allowed for the identification of LI in 33 cases (26%), compared to only 2% on H&E stained sections. Melanomas with LI showed greater thickness, higher mitotic rate and more frequent ulceration. Eleven of 33 cases with LI (33%) and 10 of 92 cases without LI (11%) were associated with a positive SLN (P = .006). More patients without LI were disease-free at last follow-up (80%) than patients with LI (50%; P = .002); LI was significantly associated with decreased progression-free survival.

CONCLUSION

The detection of LI is improved by dual immunohistochemistry and predicts SLN metastasis. The presence of LI may impact therapeutic planning in melanoma, such as the decision to perform a SLN biopsy.

Lymphatic invasion and angiotropism in primary cutaneous melanoma

Access of melanoma cells to the cutaneous vasculature either via lymphatic invasion or angiotropism is a proposed mechanism for metastasis. Lymphatic invasion is believed to be a mechanism by which melanoma cells can disseminate to regional lymph nodes and to distant sites and may be predictive of adverse outcomes. Although it can be detected on hematoxylin- and eosin-stained sections, sensitivity is markedly improved by immunohistochemistry for lymphatic endothelial cells. Multiple studies have reported a significant association between the presence of lymphatic invasion and sentinel lymph node metastasis and survival. More recently, extravascular migratory metastasis has been suggested as another means by which melanoma cells can spread. Angiotropism, the histopathologic correlate of extravascular migratory metastasis, has also been associated with melanoma metastasis and disease recurrence. Although lymphatic invasion and angiotropism are not currently part of routine melanoma reporting, the detection of these attributes using ancillary immunohistochemical stains may be useful in therapeutic planning for patients with melanoma.

D-dimers in malignant melanoma: Association with prognosis and dynamic variation in disease progress

Malignant cells elicit a chronic hemostatic activation in disease progress. This procoagulant activity does not only bear a risk for thromboembolism but also facilitates tumor growth and dissemination. An elevated plasma D-dimer level indicates an activated coagulation and fibrinolysis. In this study, the association of D-dimer levels with clinicopathological parameters and patients outcome in melanoma was investigated analyzing in total 533 melanoma patients retrospectively. Using the cut-off point of 0.6 mg/L D-dimer 145 of the total 533 patients (27.2%) were identified with elevated plasma D-dimer levels. This increased D-dimer level positively correlated with tumor thickness (p = 0.0003), lymph node invasion (p = 0.0004) and metastatic state (p <0.0001). To assess the association of D-dimer levels with progression-free survival (PFS) and overall survival (OS), long-rank test and the Cox proportional hazard model was performed. Univariate analyses revealed that elevated D-dimer levels were significantly associated with decreased PFS (HR:2.89, 95% CI (2.07-7.56), p < 0.0001) and OS (HR:2.22, 95% CI (1.06-4.57), p = 0.035). Moreover, multivariate analyses identified elevated D-dimer levels being associated with poor disease outcome (PFS:HR:2.47, 95% CI (1.23-4.98), p = 0.012; OS:HR:2.01, 95% CI (0.09-4.45), p = 0.087). Additionally, D-dimer levels were significantly increased in terminal stage patients when comparing plasma levels 0-8 versus 24-48 weeks before death (p = 0.0003). In summary, this study presents multiple evidence that elevated D-dimer levels in melanoma patients associate with poor prognosis and therefore plasma levels of D-dimers could reveal a more aggressive phenotype of melanoma and may guide the management of anti-melanoma treatment including the concept of an anti-coagulatory therapy in tumor patients.

Lymph vessels: the forgotten second circulation in health and disease

The lymphatic circulation is still a somewhat forgotten part of the circulatory system. Despite this, novel insights in lymph angiogenesis in health and disease, application of immune markers for lymphatic growth and differentiation and also the introduction of new imaging techniques to visualize the lymphatic circulation have improved our understanding of lymphatic function in both health and disease, especially in the last decade. These achievements yield better understanding of the various manifestations of lymph oedemas and malformations, and also the patterns of lymphovascular spread of cancers. Immune markers that recognize lymphatic endothelium antigens, such as podoplanin, LYVE-1 and Prox-1, can be successfully applied in diagnostic pathology and have revealed (at least partial) lymphatic differentiation in many types of vascular lesions.

Angiogenesis in melanoma: an update with a focus on current targeted therapies

Angiogenesis plays a crucial role in melanoma metastasis and progression. In recent years, numerous studies have investigated the prognostic and clinical significance of this phenomenon, and the development of molecular techniques has enabled us to achieve a better understanding of angiogenesis in melanoma. Herein, we review the current state of knowledge regarding angiogenesis in melanoma, including the pathophysiological, histological and immunohistochemical aspects of this phenomenon. We also review the molecular pathways involved in angiogenesis and the interplay between different components that might be manipulated in the future development of efficient targeted therapies. Recently developed targeted antiangiogenic therapies in clinical trials and included in the treatment of advanced-stage melanoma are also reviewed.

Prognostic Impact of Multiple Clinicopathologic Risk Factors and c-MET Overexpression in Patients Who Have Undergone Resection of Stage IB Non-Small-Cell Lung Cancer

BACKGROUND

Several studies have suggested risk factors for poor survival in stage IB non-small-cell lung cancer (NSCLC) patients. However, these factors are not definite indicators of adjuvant chemotherapy for stage IB cancer, and most of them can be used to consider adjuvant chemotherapy. We aimed to determine the clinicopathologic factors and assess whether c-MET is a prognostic factor in stage IB NSCLC patients who have undergone surgery. Additionally, we determined the relevance of the factors and the recurrence pattern in these patients.

PATIENTS AND METHODS

This study included 115 patients who underwent resection of pathologic stage IB NSCLC between January 2005 and December 2013. We retrospectively reviewed the clinicopathologic data and performed immunohistochemical analysis for c-MET. Recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were evaluated according to clinicopathologic factors and c-MET expression.

RESULTS

Lymphovascular invasion (LVI) and c-MET overexpression were significantly associated with poor RFS. A large tumor with visceral pleural invasion (VPI) or LVI, moderate/poor differentiation with LVI, and VPI with LVI were negative prognostic factors for RFS and CSS. c-MET overexpression with a large tumor, VPI, or LVI was an independent prognostic factor for poor RFS and CSS, and LVI was a significant factor for distant recurrence.

CONCLUSION

LVI and c-MET overexpression might be associated with poor prognosis in stage IB NSCLC patients. Additionally, survival might be poor in stage IB patients with multiple pathologic risk factors. Moreover, there is a high possibility of distant recurrence in patients with LVI.

Caveolin-1 mediates inflammatory breast cancer cell invasion via the Akt1 pathway and RhoC GTPase

With a propensity to invade the dermal lymphatic vessels of the skin overlying the breast and readily metastasize, inflammatory breast cancer (IBC) is arguably the deadliest form of breast cancer. We previously reported that caveolin-1 is overexpressed in IBC and that RhoC GTPase is a metastatic switch responsible for the invasive phenotype. RhoC-driven invasion requires phosphorylation by Akt1. Using a reliable IBC cell line we set out to determine if caveolin-1 expression affects RhoC-mediated IBC invasion. Caveolin-1 was down regulated by introduction of siRNA or a caveolin scaffolding domain. The ability of the cells to invade was tested and the status of Akt1 and RhoC GTPase examined. IBC cell invasion is significantly decreased when caveolin-1 is down regulated. Activation of Akt1 is decreased when caveolin-1 is down regulated, leading to decreased phosphorylation of RhoC GTPase. Thus, we report here that caveolin-1 overexpression mediates IBC cell invasion through activation Akt1, which phosphorylates RhoC GTPase.

Elastic staining does not assist detection of venous invasion in cutaneous melanoma

The aim of the present study was to determine the benefit of orcein elastic staining of primary cutaneous melanoma specimens in detecting venous invasion. Primary cutaneous melanomas in vertical growth phase were assessed for vascular invasion. All tumour blocks were stained with haematoxylin and eosin (H&E) and orcein. The cases were reviewed by two pathologists. Vascular invasion was not identified more frequently on orcein stained slides than on H&E stained ones. Elastosis and periappendiceal elastic fibres interfered with vascular invasion detection with elastic staining. Based on our study, we conclude that elastic stains such as orcein do not improve the detection rate of venous invasion in primary cutaneous melanomas.

Lymphatic and blood vasculature in primary cutaneous melanomas of the scalp and neck

BACKGROUND

Scalp/neck melanomas have a poor prognosis, possibly because of a rich vascular supply that prompts tumor cells' dissemination.

METHODS

We compared the accuracy of immunohistochemical (IHC) staining with morphology for the identification of lymphovascular invasion in 156 scalp/neck melanomas. We then analyzed the association of vessel invasion and density with pathological features and survival.

RESULTS

IHC-detected lymphatic vessel invasion (LVI) and blood vessel invasion (BVI) were identified in 34.6% and 13.5% of cases, respectively. IHC increased the LVI/BVI detection compared to morphology (40.4% vs 16.6%; p < .001). The degree of peritumoral and intratumoral blood vessel density (BVD) was greater than lymphatic vessel density (LVD). Ulceration was the only factor independently associated with intratumoral (p = .029) and peritumoral (p = .047) BVD. Tumor thickness was the only independent predictor of survival (p = .002).

CONCLUSION

IHC allows accurate assessment of lymphovascular invasion in scalp/neck melanomas. In these tumors, we observed a high incidence of BVI, which deserves further investigations.

Long-Term Outcomes of Endoscopic Versus Surgical Resection of Superficial Submucosal Colorectal Cancer

BACKGROUND

The long-term outcomes of endoscopic resection of superficial submucosal colorectal cancer (CRC) had not been adequately compared with those of surgical resection.

AIMS

We aimed to compare the long-term clinical outcomes of endoscopic resection of superficial submucosal CRC to those of surgical resection.

METHODS

Submucosal CRC patients with a tumor depth of sm1 or less than 1 mm from the muscularis mucosa were enrolled. Patients with unfavorable histology, such as poorly differentiated cancer or lymphovascular invasion, were excluded. Recurrence-free survival and overall survival were investigated in 87 patients who underwent endoscopic resection and in 171 patients who underwent surgical resection.

RESULTS

The mean ages of the endoscopic and surgical resection groups were 59.7 and 59.8 years, respectively. Hospital stay was shorter in the endoscopic resection group (1.7 ± 1.6 vs. 8.6 ± 3.8 days; p < 0.001). The 3- and 5-year recurrence-free survival rates were 98.7 and 96.7 % in the endoscopic resection group and 98.7 and 97.5 % in the surgical resection group, respectively (p = 0.837). The 3- and 5-year overall survival rates were 100.0 and 95.2 % in the endoscopic resection group and 98.7 and 92.8 % in the surgical resection group, respectively (p = 0.928). Recurred cases showed an unfavorable histology that was overlooked at the time of initial resection.

CONCLUSIONS

Long-term outcomes after endoscopic resection of superficial submucosal CRC are comparable to those after surgical resection. Thorough initial histopathological evaluations are needed to guarantee the correct indication for endoscopic resection of submucosal CRC.

Immunohistochemistry in dermatopathology

CONTEXT

Immunohistochemistry is not a diagnostic test but a highly valuable tool that requires interpretation within a context.

OBJECTIVE

To review the current status and limitations of immunohistochemistry in dermatopathology.

DATA SOURCES

English-language literature published between 1980 and 2014.

CONCLUSIONS

Although immunohistochemistry is rarely completely specific or sensitive, it is an important adjunctive technique in dermatopathology and can be helpful in a series of diagnostic dilemmas.

Microvessel density, lymphovascular density, and lymphovascular invasion in primary cutaneous melanoma-correlation with histopathologic prognosticators and BRAF status

The relationship between microvessel density (MVD), lymphovascular density (LVD), and lymphovascular invasion (LVI) in primary cutaneous melanoma (PCM) remains unclear. Given this, a total of 102 PCMs were assessed for MVD (vascular endothelial growth factor receptor 2 and Endocan), LVD (D2-40), and LVI (immunostaining with D2-40/S-100 and hematoxylin and eosin); tumoral S-100A13, vascular endothelial growth factor receptor 2, and Endocan; and BRAF status. LVD was associated with MVD (P = .01). MVD was higher in PCMs with depth greater than or equal to 2 mm and ulceration (P = .04, .05), whereas LVD was higher in PCMs with depth greater than or equal to 2 mm and mitoses (P = .03, .02). After adjusting for MVD and LVD, only ulceration was associated with LVI (P < .02). A BRAF mutation was seen in 30.4% cases, and when present, both LVD and host response (P = .0008 and .04, respectively) were significantly associated with MVD. Immunostaining with S-100A13 was noted in 99% of cases and a significant association noted only with ulceration (P = .05). Immunostaining increased LVI positivity (46.5% versus 4.9% by hematoxylin and eosin, P < .0001). MVD and LVD are not associated with LVI, appear to be closely related with each other, and are associated with select markers of poor prognosticative value. The association between a host response and LVD and MVD in PCMs with a BRAF mutation suggests that they exhibit potential for strategizing immunotherapies.

Emerging clinical applications of selected biomarkers in melanoma

Melanoma is a lethal skin disease with a mostly predictable clinical course according to a known constellation of clinical and pathologic features. The distinction of melanoma from benign melanocytic nevus is typically unequivocol; however, there is a subset of tumors known for its diagnostic challenges, development of late metastases, and difficulties in treatment. Several melanocytic tissue biomarkers are available that can facilitate the histopathologic interpretation of melanoma as well as provide insight into the biologic potential and mutational status of this disease. This review describes the clinical application of some of these established and emerging tissue biomarkers available to assess melanocytic differentiation, vascular invasion, mitotic capacity, and mutation status. The selected tissue biomarkers in this review include MiTF, Sox10, D2-40, PHH3, H3KT (anti-H3K79me3T80ph), anti-BRAFV600E, and anti-BAP-1.

The clinicopathological and gene expression patterns associated with ulceration of primary melanoma

Ulceration of primary melanomas is associated with poor prognosis yet is reported to predict benefit from adjuvant interferon. To better understand the biological processes involved, clinicopathological factors associated with ulceration were determined in 1804 patients. From this cohort, 348 primary tumor blocks were sampled to generate gene expression data using a 502-gene cancer panel and 195 blocks were used for immunohistochemistry to detect macrophage infiltration and vessel density. Gene expression results were validated using a whole genome array in two independent sample sets. Ulceration of primary melanomas was associated with more proliferative tumors, tumor vessel invasion, and increased microvessel density. Infiltration of tumors with greater number of macrophages and gene expression pathways associated with wound healing and up-regulation of pro-inflammatory cytokines suggests that ulceration is associated with tumor-related inflammation. The relative benefit from interferon reported in patients with ulcerated tumors may reflect modification of signaling pathways involved in inflammation.

Enhanced immunohistochemical detection of neural infiltration in primary melanoma: is there a clinical value?

Neural infiltration in primary melanoma is a histopathologic feature that has been associated with desmoplastic histopathologic subtype and local recurrence in the literature. We tested the hypothesis that improved detection and characterization of neural infiltration into peritumoral or intratumoral location and perineural or intraneural involvement could have a prognostic relevance. We studied 128 primary melanoma cases prospectively accrued and followed at New York University using immunohistochemical detection with antihuman neurofilament protein and routine histology with hematoxylin and eosin. Neural infiltration, defined as the presence of tumor cells involving or immediately surrounding nerve foci, was identified and characterized using both detection methods. Neural infiltration rate of detection was enhanced by immunohistochemistry for neurofilament in matched-pair design (47% by immunohistochemistry versus 25% by routine histology). Immunohistochemical detection of neural infiltration was significantly associated with ulceration (P = .021), desmoplastic and acral lentiginous histologic subtype (P = .008), and head/neck/hands/feet tumor location (P = .037). Routinely detected neural infiltration was significantly associated with local recurrence (P = .010). Immunohistochemistry detected more intratumoral neural infiltration cases compared with routine histology (30% versus 3%, respectively). Peritumoral and intratumoral nerve location had no impact on clinical outcomes. Using a multivariate model controlling for stage, neither routinely detected neural infiltration nor enhanced immunohistochemical characterization of neural infiltration was significantly associated with disease-free or overall survival. Our data demonstrate that routinely detected neural infiltration is associated with local recurrence in all histologic subtypes but that improved detection and characterization of neural infiltration with immunohistochemistry in primary melanoma does not add to prognostic relevance.

Tissue prognostic biomarkers in primary cutaneous melanoma

Cutaneous melanoma (CM) causes the greatest number of skin cancer-related deaths worldwide. Predicting CM prognosis is important to determine the need for further investigation, counseling of patients, to guide appropriate management (particularly the need for postoperative adjuvant therapy), and for assignment of risk status in groups of patients entering clinical trials. Since recurrence rate is largely independent from stages defined by morphological and morphometric criteria, there is a strong need for identification of additional robust prognostic factors to support decision-making processes. Most data on prognostic biomarkers in melanoma have been evaluated in tumor tissue samples by conventional morphology and immunohistochemistry (IHC) as well as DNA and RNA analyses. In the present review, we critically summarize main high-quality studies investigating IHC-based protein biomarkers of melanoma outcome according to Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK)-derived criteria. Pathways have been classified and conveyed in the "biologic road" previously described by Hanahan and Weinberg. Data derived from genomic and transcriptomic technologies have been critically reviewed to better understand if any of investigated proteins or gene signatures should be incorporated into clinical practice or still remain a field of melanoma research. Despite a wide body of research, no molecular prognostic biomarker has yet been translated into clinical practice. Conventional tissue biomarkers, such as Breslow thickness, ulceration, mitotic rate and lymph node positivity, remain the backbone prognostic indicators in melanoma.

Lymphatic invasion as a prognostic biomarker in primary cutaneous melanoma

Melanoma has a propensity for lymph node metastasis. However, the incidence of lymphatic invasion detected by histology alone in primary melanoma is disproportionately low in comparison to the incidence of positive sentinel lymph nodes (SLN). With the discovery of lymphatic endothelial cell markers, such as podoplanin and LYVE-1, lymphatic vessels can be reliably detected in formalin-fixed paraffin-embedded (FFPE) tissues. There is a now consensus that lymphatic invasion detected by immunohistochemical stains in primary melanoma is much more common than previously reported by histological examination alone. Immunohistochemical stains show that lymphangiogenesis and lymphatic invasion in primary melanoma may occur intratumorally or peritumorally, and lymphatic invasion is common across the range of tumor thicknesses in primary vertical growth phase (VGP) melanomas. A number of studies have shown that lymphatic invasion in primary melanoma is associated with a positive sentinel lymph node biopsy and a worse clinical outcome. Although not currently a part of the standard of care for staging of melanoma, the detection of lymphatic invasion in primary melanoma using immunohistochemical markers may be helpful in planning of therapy in some cases and may find a routine role in primary melanoma microscopic attributes in future.

Outcomes and prognostic factors in superficial spreading melanoma

BACKGROUND

Prognostic factors and risk factors for positive sentinel lymph node (SLN) biopsy results are important to identify in superficial spreading melanoma (SSM).

METHODS

A single-center database and a prospective clinical trial database were reviewed for all patients with diagnoses of SSM. Logistic regression, Kaplan-Meier survival analysis, and univariate and multivariate Cox models were used.

RESULTS

A total of 1,643 patients with SSM were identified. Independent risk factors for positive SLN biopsy results were Breslow thickness (BT) ≥2.0 mm, age <60 years, and presence of ulceration. BT ≥2.0 mm, ulceration, lymphovascular invasion, and positive SLN and positive non-SLN biopsy results were independent risk factors for worse disease-free survival. Independent overall survival risk factors included BT ≥2.0 mm, age ≥60 years, ulceration, nonextremity tumor location, lymphovascular invasion, and positive SLN biopsy results.

CONCLUSIONS

BT, ulceration, lymphovascular invasion, and SLN and non-SLN status are important risk factors for SSM.