Large cell neuroendocrine carcinoma with a solitary brain metastasis and low Ki-67:a unique subtype

INTRODUCTION: Stage IV large cell neuroendocrine carcinoma (LCNEC) of the lung generally presents as disseminated and aggressive disease with a Ki-67 proliferation index (PI) 40-80%. LCNEC can be subdivided in two main subtypes: the first harboring TP53/RB1 mutations (small cell lung carcinoma (SCLC)-like), the second with mutations in TP53 and STK11/KEAP1 (non-small cell lung carcinoma (NSCLC)-like). Here we evaluated 11 LCNEC patients with only a solitary brain metastasis and evaluate phenotype, genotype and follow-up. METHODS: Eleven LCNEC patients with solitary brain metastases were analyzed. Clinical characteristics and survival data were retrieved from medical records. Pathological analysis included histomorphological analysis, immunohistochemistry (pRB and Ki-67 PI) and next generation sequencing (TP53, RB1, STK11, KEAP1 and MEN1). RESULTS: All patients had N0 or N1 disease. Median overall survival (OS) was 12 months (95% confidence interval (CI) 5.5-18.5 months). Mean Ki-67 PI was 59% (range 15-100%). In 6/11 LCNEC Ki-67 PI was ≤40%. OS was longer for Ki-67 ≤40% compared to >40% (17 months (95% CI 11-23 months) vs. 5 months (95% CI 0.7-9 months), p=0.007). Two patients were still alive at follow-up after 86 and 103 months, both had Ki-67 ≤40%. 8/11 patients could be subclassified and both SCLC-like (n=6) and NSCLC-like (n=2) subtype were present. No MEN1 mutation was found. CONCLUSION: Stage IV LCNEC with a solitary brain metastasis and N0/N1 disease show in the majority of cases Ki-67 PI ≤40% and prolonged survival, distinguishing them from general LCNEC. This unique subgroup can be both of the SCLC-like and NSCLC-like subtype

Genomic Landscape of Spitzoid Neoplasms Impacting Patient Management

Spitzoid neoplasms are a distinct group of melanocytic proliferations characterized by epithelioid and/ or spindle shaped melanocytes. Intermediate forms that share features of both benign Spitz nevi (SN) and Spitz melanoma, i.e., malignant Spitz tumor (MST) represent a diagnostically and clinically challenging group of melanocytic lesions. A multitude of descriptive diagnostic terms exist for these ambiguous lesions with atypical Spitz tumor (AST) or Spitz tumor of uncertain malignant potential (STUMP) just naming two of them. This diagnostic gray zone creates confusion and high insecurity in clinicians and in patients. Biological behavior and clinical course of this intermediate group still remains largely unknown, often leading to difficulties with uncertainties in clinical management and prognosis. Consequently, a better stratification of Spitzoid neoplasms in benign and malignant forms is required thereby keeping the diagnostic group of AST/STUMP as small as possible. Ancillary diagnostic techniques such as immunohistochemistry, comparative genomic hybridization, fluorescence in situ hybridization, next generation sequencing, micro RNA and mRNA analysis as well as mass spectrometry imaging offer new opportunities for the distinct diagnosis, thereby allowing the best clinical management of Spitzoid neoplasms. This review gives an overview on these additional diagnostic techniques and the recent developments in the field of molecular genetic alterations in Spitzoid neoplasms. We also discuss how the recent findings might facilitate the diagnosis and stratification of atypical Spitzoid neoplasms and how these findings will impact the diagnostic work up as well as patient management. We suggest a stepwise implementation of ancillary diagnostic techniques thereby integrating immunohistochemistry and molecular pathology findings in the diagnosis of challenging ambiguous Spitzoid neoplasms. Finally, we will give an outlook on pending future research objectives in the field of Spitzoid melanocytic lesions

In-depth molecular analysis of combined and co-primary pulmonary large cell neuroendocrine carcinoma and adenocarcinoma

Up to 14% of large cell neuroendocrine carcinomas (LCNECs) are diagnosed in continuity with nonsmall cell lung carcinoma. In addition to these combined lesions, 1% to 7% of lung tumors present as co-primary tumors with multiple synchronous lesions. We evaluated molecular and clinicopathological characteristics of combined and co-primary LCNEC-adenocarcinoma (ADC) tumors. Ten patients with LCNEC-ADC (combined) and five patients with multiple synchronous ipsilateral LCNEC and ADC tumors (co-primary) were included. DNA was isolated from distinct tumor parts, and 65 cancer genes were analyzed by next generation sequencing. Immunohistochemistry was performed including neuroendocrine markers, pRb, Ascl1 and Rest. Pure ADC (N = 37) and LCNEC (N = 17) cases were used for reference. At least 1 shared mutation, indicating tumor clonality, was found in LCNEC- and ADC-parts of 10/10 combined tumors but only in 1/5 co-primary tumors. A range of identical mutations was observed in both parts of combined tumors: 8/10 contained ADC-related (EGFR/KRAS/STK11 and/or KEAP1), 4/10 RB1 and 9/10 TP53 mutations. Loss of pRb IHC was observed in 6/10 LCNEC- and 4/10 ADC-parts. The number and intensity of expression of Ascl1 and neuroendocrine markers increased from pure ADC (low) to combined ADC (intermediate) and combined and pure LCNEC (high). The opposite was true for Rest expression. In conclusion, all combined LCNEC-ADC tumors were clonally related indicating a common origin. A relatively high frequency of pRb inactivation was observed in both LCNEC- and ADC-parts, suggesting an underlying role in LCNEC-ADC development. Furthermore, neuroendocrine differentiation might be modulated by Ascl1(+) and Rest(-) expression

Detection of Merkel Cell Polyomavirus in Seborrheic Keratosis

Seborrheic keratosis (SK) is the most common benign cutaneous neoplasm. A subset shows increased p16 expression. Since SK shares several features with verruca vulgaris, e.g., increased p16 expression, human papillomaviruses (HPV) have been suggested as possible causal agents. However, a relevant association could not be established between HPV and SK. In the present study we aimed to investigate the presence of Merkel cell polyomavirus (MCPyV) in relation to p16 expression in SK. P16 expression was investigated using immunohistochemistry (IHC). Presence of MCPyV was assessed in 23 formalin-fixed paraffin-embedded tissue samples of SK by molecular techniques (i.e., PCR and FISH) and IHC. 16/23 SK showed strong to moderate p16 expression. 6/23 of SK were MCPyV positive by PCR which was confirmed by FISH. Of interest, two samples with strong FISH signals also showed MCPyV expression as tested by IHC. Samples with weaker signal intensity were negative in IHC. P16 expression was not associated with the presence of MCPyV. Concluding, the detection of MCPyV DNA by PCR and FISH in SK reflects the widespread prevalence of MCPyV in the skin. However, low detection rates exclude MCPyV as a major pathogenic factor in SK, most likely representing a coincidental infection. P16 IHC does not appear as useful adjunctive surrogate marker for the presence of MCPyV in SK

Genomic Landscape of Spitzoid Neoplasms Impacting Patient Management

Spitzoid neoplasms are a distinct group of melanocytic proliferations characterized by epithelioid and/ or spindle shaped melanocytes. Intermediate forms that share features of both benign Spitz nevi (SN) and Spitz melanoma, i.e., malignant Spitz tumor (MST) represent a diagnostically and clinically challenging group of melanocytic lesions. A multitude of descriptive diagnostic terms exist for these ambiguous lesions with atypical Spitz tumor (AST) or Spitz tumor of uncertain malignant potential (STUMP) just naming two of them. This diagnostic gray zone creates confusion and high insecurity in clinicians and in patients. Biological behavior and clinical course of this intermediate group still remains largely unknown, often leading to difficulties with uncertainties in clinical management and prognosis. Consequently, a better stratification of Spitzoid neoplasms in benign and malignant forms is required thereby keeping the diagnostic group of AST/STUMP as small as possible. Ancillary diagnostic techniques such as immunohistochemistry, comparative genomic hybridization, fluorescence in situ hybridization, next generation sequencing, micro RNA and mRNA analysis as well as mass spectrometry imaging offer new opportunities for the distinct diagnosis, thereby allowing the best clinical management of Spitzoid neoplasms. This review gives an overview on these additional diagnostic techniques and the recent developments in the field of molecular genetic alterations in Spitzoid neoplasms. We also discuss how the recent findings might facilitate the diagnosis and stratification of atypical Spitzoid neoplasms and how these findings will impact the diagnostic work up as well as patient management. We suggest a stepwise implementation of ancillary diagnostic techniques thereby integrating immunohistochemistry and molecular pathology findings in the diagnosis of challenging ambiguous Spitzoid neoplasms. Finally, we will give an outlook on pending future research objectives in the field of Spitzoid melanocytic lesions.status: publishe

Rethinking the biology of metastatic melanoma:a holistic approach

Over the past decades, melanoma-related mortality has remained nearly stable. The main reason is treatment failure of metastatic disease and the inherently linked knowledge gap regarding metastasis formation. In order to elicit invasion, melanoma cells manipulate the tumor microenvironment, gain motility, and adhere to the extracellular matrix and cancer-associated fibroblasts. Melanoma cells thereby express different cell adhesion molecules like laminins, integrins, N-cadherin, and others. Epithelial-mesenchymal transition (EMT) is physiological during embryologic development, but reactivated during malignancy. Despite not being truly epithelial, neural crest-derived malignancies like melanoma share similar biological programs that enable tumorigenesis, invasion, and metastasis. This complex phenomenon is termed phenotype switching and is intertwined with oncometabolism as well as dormancy escape. Additionally, it has been shown that primary melanoma shed exosomes that create a favorable premetastatic niche in the microenvironment of secondary organs and lymph nodes. Although the growing body of literature describes the aforementioned concepts separately, an integrative holistic approach is missing. Using melanoma as a tumor model, this review will shed light on these complex biological principles in an attempt to clarify the mechanistic metastatic pathways that dictate tumor and patient fate

Refining the Diagnosis of Congenital Nephrotic Syndrome on Long-term Stored Tissue: c.1097G>A (p.(Arg366His)) WT1 Mutation Causing Denys Drash Syndrome

Contains fulltext : 168099.pdf (Publisher’s version ) (Open Access)Congenital nephrotic syndrome (CNS) caused by a mutation in the Wilms tumor 1 suppressor gene (WT1) is part of Denys Drash Syndrome or Frasier syndrome. In the framework of genetic counseling, the diagnosis of CNS can be refined with gene mutation studies on long-term stored formalin-fixed paraffin-embedded tissue from postmortem examination. We report a case of diffuse mesangial sclerosis with perinatal death caused by a de novo mutation in the WT1 gene in a girl with an XY-genotype. This is the first case of Denys Drash Syndrome with the uncommon missense c.1097G>A [p.(Arg366His)] mutation in the WT1 gene which has been diagnosed on long-term stored formalin-fixed paraffin-embedded tissue in 1993. This emphasizes the importance of retained and adequately stored tissue as a resource in the ongoing medical care and counseling

A digital mRNA expression signature to classify challenging Spitzoid melanocytic neoplasms

Spitzoid neoplasms are a challenging group of cutaneous melanocytic proliferations. They are characterized by epithelioid and/or spindle-shaped melanocytes and classified as benign Spitz nevi (SN), atypical Spitz tumors (AST), or malignant Spitz tumors (MST). The intermediate AST category represents a diagnostically challenging group since on purely histopathological grounds, their benign or malignant character remains unpredictable. This results in uncertainties in patient treatment and prognosis. The molecular properties of Spitzoid lesions, especially their transcriptomic landscape, remain poorly understood, and genomic alterations in melanoma-associated oncogenes are typically absent. The aim of this study was to characterize their transcriptome with digital mRNA expression profiling. Formalin-fixed paraffin-embedded samples (including 27 SN, 10 AST, and 14 MST) were analyzed using the NanoString nCounter PanCancer Pathways Panel. The number of significantly differentially expressed genes in SN vs. MST, SN vs. AST, and AST vs. MST was 68, 167, and 18, respectively. Gene set enrichment analysis revealed upregulation of pathways related to epithelial-mesenchymal transition and immunomodulatory-, angiogenesis-, hormonal-, and myogenesis-associated processes in AST and MST. A molecular signature of SN vs. MST was discovered based on the top-ranked most informative genes: NRAS, NF1, BMP2, EIF2B4, IFNA17, and FZD9. The AST samples showed intermediate levels of the identified signature. This implies that the gene signature can potentially be used to distinguish high-grade from low-grade AST with a larger study cohort in the future. This combined histopathological and transcriptomic methodology is promising for prospective diagnostics of Spitzoid neoplasms and patient management in dermatological oncology.status: publishe

A digital mRNA expression signature to classify challenging Spitzoid melanocytic neoplasms

Spitzoid neoplasms are a challenging group of cutaneous melanocytic proliferations. They are characterized by epithelioid and/or spindle-shaped melanocytes and classified as benign Spitz nevi (SN), atypical Spitz tumors (AST), or malignant Spitz tumors (MST). The intermediate AST category represents a diagnostically challenging group since on purely histopathological grounds, their benign or malignant character remains unpredictable. This results in uncertainties in patient treatment and prognosis. The molecular properties of Spitzoid lesions, especially their transcriptomic landscape, remain poorly understood, and genomic alterations in melanoma-associated oncogenes are typically absent. The aim of this study was to characterize their transcriptome with digital mRNA expression profiling. Formalin-fixed paraffin-embedded samples (including 27 SN, 10 AST, and 14 MST) were analyzed using the NanoString nCounter PanCancer Pathways Panel. The number of significantly differentially expressed genes in SN vs. MST, SN vs. AST, and AST vs. MST was 68, 167, and 18, respectively. Gene set enrichment analysis revealed upregulation of pathways related to epithelial-mesenchymal transition and immunomodulatory-, angiogenesis-, hormonal-, and myogenesis-associated processes in AST and MST. A molecular signature of SN vs. MST was discovered based on the top-ranked most informative genes: NRAS, NF1, BMP2, EIF2B4, IFNA17, and FZD9. The AST samples showed intermediate levels of the identified signature. This implies that the gene signature can potentially be used to distinguish high-grade from low-grade AST with a larger study cohort in the future. This combined histopathological and transcriptomic methodology is promising for prospective diagnostics of Spitzoid neoplasms and patient management in dermatological oncology

A digital mRNA expression signature to classify challenging Spitzoid melanocytic neoplasms

Spitzoid neoplasms are a challenging group of cutaneous melanocytic proliferations. They are characterized by epithelioid and/or spindle-shaped melanocytes and classified as benign Spitz nevi (SN), atypical Spitz tumors (AST), or malignant Spitz tumors (MST). The intermediate AST category represents a diagnostically challenging group since on purely histopathological grounds, their benign or malignant character remains unpredictable. This results in uncertainties in patient treatment and prognosis. The molecular properties of Spitzoid lesions, especially their transcriptomic landscape, remain poorly understood, and genomic alterations in melanoma-associated oncogenes are typically absent. The aim of this study was to characterize their transcriptome with digital mRNA expression profiling. Formalin-fixed paraffin-embedded samples (including 27 SN, 10 AST, and 14 MST) were analyzed using the NanoString nCounter PanCancer Pathways Panel. The number of significantly differentially expressed genes in SN vs. MST, SN vs. AST, and AST vs. MST was 68, 167, and 18, respectively. Gene set enrichment analysis revealed upregulation of pathways related to epithelial-mesenchymal transition and immunomodulatory-, angiogenesis-, hormonal-, and myogenesis-associated processes in AST and MST. A molecular signature of SN vs. MST was discovered based on the top-ranked most informative genes: NRAS, NF1, BMP2, EIF2B4, IFNA17, and FZD9. The AST samples showed intermediate levels of the identified signature. This implies that the gene signature can potentially be used to distinguish high-grade from low-grade AST with a larger study cohort in the future. This combined histopathological and transcriptomic methodology is promising for prospective diagnostics of Spitzoid neoplasms and patient management in dermatological oncology