Cutaneous carcinosarcoma: further insights into its mutational landscape through massive parallel genome sequencing

ZEB2 drives intra-tumor heterogeneity and skin squamous cell carcinoma formation with distinct EMP transition states

About 5% of patients with cutaneous squamous cell carcinoma (cSCC) have a poor prognosis which is associated with a loss of tumor differentiation, invasion and metastasis, all of which are linked to the process of epithelial-to-mesenchymal plasticity (EMP). Here, we showed that the EMP-associated transcription factor ZEB2 drives cSCC heterogeneity which resembles biphasic carcinosarcoma-like tumors. Single cell RNA sequencing revealed distinct subpopulations ranging from fully epithelial (E) to intermediate (EM) to fully mesenchymal (M), associated with the gradual loss of cell surface markers EPCAM, CDH1, ITGB4, and CD200. Mesenchymal features were associated with a higher metastatic capacity and anoikis resistance, yet this comes with a sensitivity toward TNF-induced cell death. Altogether we provide insights in cSCC heterogeneity and modes to target mesenchymal-metastasis inducing cells.

The Rarity in the Rarity: Presentation of Three Cases of Cutaneous Carcinosarcoma with Clinical and Histopathological Insights

A cutaneous carcinosarcoma (cCS) is a rare and aggressive skin cancer characterized by both carcinomatous (epithelial) and sarcomatous (mesenchymal) components, making it a biphasic tumor. Despite its occurrence in various organs, a cCS is exceptionally rare in the skin, predominantly affecting older males. The etiology of a cCS is unclear, but it may originate from a single progenitor cell capable of dual differentiation or from a collision of carcinoma and sarcoma cells. Clinically, a cCS presents as a rapidly growing, painful, ulcerated nodule or plaque on sun-exposed skin, with a high risk of local invasion and metastasis. Histopathologically, a cCS includes various epithelial components, such as squamous cell carcinoma and basal cell carcinoma, along with undifferentiated sarcomatous components resembling atypical fibroxanthoma. The tumor may also exhibit heterologous differentiation like angiosarcomatous or rhabdomyosarcomatous features. We present three cases of a cCS, highlighting their clinical and histological characteristics and comparing them with previously reported cases. Understanding a cCS is complicated by its rarity and diverse presentation, emphasizing the need for further research to elucidate its pathogenesis and optimal management.

Trichoblastic carcinosarcoma of the neck: Case report and molecular analysis of a seldom, relapsing entity and a review of the literature

Trichoblastic carcinosarcoma is a seldom biphasic adnexal tumor with malignant epithelial and mesenchymal components. The authors report the first tumor on the neck developed from preexistent trichoblastoma showing aggressive, recurrent behavior. An 82-year-old man presented with a solitary 3-cm exophytic lesion. Histology verified the diagnosis of trichoblastic carcinosarcoma. Four years earlier, a trichoblastic carcinoma arising in a preexisting trichoblastoma was excised at the same location. Despite successful surgical treatments, three local recurrences within 4 years were diagnosed. After the second relapse, the patient agreed on adjuvant radiation. Twelve months later, another relapse was excised in toto. In the last surgical specimen, only the mesenchymal component was found. Copy number variation analysis of the preexisting tumor and two recurrences revealed the same entity and additional chromosomal aberrations in the recurrences. Adnexal carcinosarcomas are seldom, yet presumably underdiagnosed biphasic tumors with aggressive growth potential. They should have adequate preoperative clarification with wide tumor excision, as radiosensitivity seems to be of limited effect.

Next-Generation Sequencing Analysis of Pancreatic Cancer Using Residual Liquid Cytology Specimens from Endoscopic Ultrasound—Guided Fine-Needle Biopsy: A Prospective Comparative Study with Tissue Specimens

This study evaluated the feasibility and clinical utility of liquid-based cytology (LBC) specimens via endoscopic ultrasound–guided fine-needle biopsy (EUS-FNB) for next-generation sequencing (NGS) of pancreatic cancer (PC). We prospectively evaluated the performance of DNA extraction and NGS using EUS-FNB samples obtained from PC. Thirty-three consecutive patients with PC who underwent EUS-FNB at our hospital were enrolled. DNA samples were obtained from 96.8% of the patients. When stratified with a variant allele frequency (VAF) > 10% tumor burden, the NGS success rate was 76.7% (n = 23) in formalin-fixed paraffin-embedded (FFPE), 83.3% (n = 25) in LBC, and 76.7% (n = 23) in frozen samples. The overall NGS success rate was 86.7% (n = 26) using FFPE, LBC, or frozen samples. The detection rates for the main mutated genes were as follows: 86.7% for KRAS, 73.3% for TP53, 66.7% for CDKN2A, 36.7% for SMAD4, and 16.7% for ARID1A. LBC had the highest median value of VAF (23.5%) for KRAS and TP53. PC mutation analysis using NGS was successfully performed using LBC compared with FFPE and frozen samples. This approach provides an alternative and affordable source of molecular testing materials.

Contribution of mechanical homeostasis to epithelial-mesenchymal transition

BACKGROUND

Metastasis refers to the spread of cancer cells from a primary tumor to other parts of the body via the lymphatic system and bloodstream. With tremendous effort over the past decades, remarkable progress has been made in understanding the molecular and cellular basis of metastatic processes. Metastasis occurs through five steps, including infiltration and migration, intravasation, survival, extravasation, and colonization. Various molecular and cellular factors involved in the metastatic process have been identified, such as epigenetic factors of the extracellular matrix (ECM), cell-cell interactions, soluble signaling, adhesion molecules, and mechanical stimuli. However, the underlying cause of cancer metastasis has not been elucidated.

CONCLUSION

In this review, we have focused on changes in the mechanical properties of cancer cells and their surrounding environment to understand the causes of cancer metastasis. Cancer cells have unique mechanical properties that distinguish them from healthy cells. ECM stiffness is involved in cancer cell growth, particularly in promoting the epithelial-mesenchymal transition (EMT). During tumorigenesis, the mechanical properties of cancer cells change in the direction opposite to their environment, resulting in a mechanical stress imbalance between the intracellular and extracellular domains. Disruption of mechanical homeostasis may be one of the causes of EMT that triggers the metastasis of cancer cells.

A Comprehensive Review of Performance of Next-Generation Sequencing Platforms

Background

Next-generation sequencing methods have been developed and proposed to investigate any query in genomics or clinical activity involving DNA. Technical advancement in these sequencing methods has enhanced sequencing volume to several billion nucleotides within a very short time and low cost. During the last few years, the usage of the latest DNA sequencing platforms in a large number of research projects helped to improve the sequencing methods and technologies, thus enabling a wide variety of research/review publications and applications of sequencing technologies.

Objective

The proposed study is aimed at highlighting the most fast and accurate NGS instruments developed by various companies by comparing output per hour, quality of the reads, maximum read length, reads per run, and their applications in various domains. This will help research institutions and biological/clinical laboratories to choose the sequencing instrument best suited to their environment. The end users will have a general overview about the history of the sequencing technologies, latest developments, and improvements made in the sequencing technologies till now.

Results

The proposed study, based on previous studies and manufacturers' descriptions, highlighted that in terms of output per hour, Nanopore PromethION outperformed all sequencers. BGI was on the second position, and Illumina was on the third position.

Conclusion

The proposed study investigated various sequencing instruments and highlighted that, overall, Nanopore PromethION is the fastest sequencing approach. BGI and Nanopore can beat Illumina, which is currently the most popular sequencing company. With respect to quality, Ion Torrent NGS instruments are on the top of the list, Illumina is on the second position, and BGI DNB is on the third position. Secondly, memory- and time-saving algorithms and databases need to be developed to analyze data produced by the 3rd- and 4th-generation sequencing methods. This study will help people to adopt the best suited sequencing platform for their research work, clinical or diagnostic activities.

A tEMTing target? Clinical and experimental evidence for epithelial-mesenchymal transition in the progression of cutaneous squamous cell carcinoma (a scoping systematic review)

Cutaneous squamous cell carcinoma (cSCC) is a disease with globally rising incidence and poor prognosis for patients with advanced or metastatic disease. Epithelial-mesenchymal transition (EMT) is a driver of metastasis in many carcinomas, and cSCC is no exception. We aimed to provide a systematic overview of the clinical and experimental evidence for EMT in cSCC, with critical appraisal of type and quality of the methodology used. We then used this information as rationale for potential drug targets against advanced and metastatic cSCC. All primary literature encompassing clinical and cell-based or xenograft experimental studies reporting on the role of EMT markers or related signalling pathways in the progression of cSCC were considered. A screen of 3443 search results yielded 86 eligible studies comprising 44 experimental studies, 22 clinical studies, and 20 studies integrating both. From the clinical studies a timeline illustrating the alteration of EMT markers and related signalling was evident based on clinical progression of the disease. The experimental studies reveal connections of EMT with a multitude of factors such as genetic disorders, cancer-associated fibroblasts, and matrix remodelling via matrix metalloproteinases and urokinase plasminogen activator. Additionally, EMT was found to be closely tied to environmental factors as well as to stemness in cSCC via NFκB and β-catenin. We conclude that the canonical EGFR, canonical TGF-βR, PI3K/AKT and NFκB signalling are the four signalling pillars that induce EMT in cSCC and could be valuable therapeutic targets. Despite the complexity, EMT markers and pathways are desirable biomarkers and drug targets for the treatment of advanced or metastatic cSCC.

Interplay between tumor microenvironment and partial EMT as the driver of tumor progression

Epithelial-to-mesenchymal transition (EMT), an evolutionary conserved phenomenon, has been extensively studied to address the unresolved variable treatment response across therapeutic regimes in cancer subtypes. EMT has long been envisaged to regulate tumor invasion, migration, and therapeutic resistance during tumorigenesis. However, recently it has been highlighted that EMT involves an intermediate partial EMT (pEMT) phenotype, defined by incomplete loss of epithelial markers and incomplete gain of mesenchymal markers. It has been further emphasized that pEMT transition involves a spectrum of intermediate hybrid states on either side of pEMT spectrum. Emerging evidence underlines bi-directional crosstalk between tumor cells and surrounding microenvironment in acquisition of pEMT phenotype. Although much work is still ongoing to gain mechanistic insights into regulation of pEMT phenotype, it is evident that pEMT plays a critical role in tumor aggressiveness, invasion, migration, and metastasis along with therapeutic resistance. In this review, we focus on important role of tumor-intrinsic factors and tumor microenvironment in driving pEMT and emphasize that engineered controlled microenvironments are instrumental to provide mechanistic insights into pEMT biology. We also discuss the significance of pEMT in regulating hallmarks of tumor progression i.e. cell cycle regulation, collective migration, and therapeutic resistance. Although constantly evolving, current progress and momentum in the pEMT field holds promise to unravel new therapeutic targets to halt tumor progression at early stages as well as tackle the complex therapeutic resistance observed across many cancer types.

•

Partial EMT phenotype drives key hallmarks of tumor progression

•

Role of tumor microenvironment in pEMT phenotype via cellular signaling pathways

•

Engineering 3D in vitro models to study pEMT phenotype

•

Opportunities and challenges in understanding pEMT phenotype

Trichoblastic carcinosarcoma in a 34-year-old woman with histopathologic and molecular analysis, including re-demonstration of a CDKN2A p.(R58*) mutation

Trichoblastic carcinosarcomas are rare, adnexal-type cutaneous carcinosarcomas that are thought to be related histogenetically to trichoblastomas, yet in which both the epithelial and stromal components show features of malignancy. Ten cases have been described in the literature thus far, with a predilection for the head and neck of older males. We present a case of cutaneous carcinosarcoma in sun-damaged skin of a 34-year-old woman showing features of a trichoblastic carcinosarcoma, with histopathologic analysis along with targeted next-generation sequencing of 50 cancer-associated genes. Two pathogenic variants in TP53 were identified, p.(R158C), p.(R273P), along with a likely pathogenic variant CDKN2A, p.(R58*). In particular, it is noted that the CDKN2A p.(R58*) missense mutation has been described in two previous cases of cutaneous carcinosarcomas, including a case of trichoblastic carcinosarcoma.

Cutaneous adnexal carcinosarcoma: Immunohistochemical and molecular evidence of epithelial mesenchymal transition

Cutaneous carcinosarcomas are rare biphenotypic tumors that simultaneously show epithelial and mesenchymal differentiation. The most common carcinomatous components in skin carcinosarcomas are basal cell carcinoma and squamous cell carcinoma; adnexal carcinomas are rarely encountered. We report a case of an adnexal carcinoma with ductal and squamous differentiation and spindle cell component, which is interpreted as carcinosarcoma. Loss of immunohistochemical expression of E-cadherin and β-catenin detected in the sarcomatous component suggested epithelial mesenchymal transition (EMT). RNA sequencing analysis identified several gene mutations and alterations such as translocations and upregulations/downregulations, either shared by the two components of the tumor or differentially present in the carcinoma or the sarcoma parts. Thus, mutations in genes, such as TP53, were found in both components of the tumor while mutations in PDGFRA and RB1 (a pathogenic missense mutation) were exclusively present in the sarcomatous areas, further supporting EMT. EMT is a dynamic process by which tumors acquire mesenchymal phenotype while simultaneously losing epithelial properties. Although the pathways involved in EMT have been extensively studied, this phenomenon still needs to be investigated in cutaneous tumors of adnexal origin for a better understanding of their pathogenesis. These molecular changes may represent promising targets for personalized therapies.

Trichoblastic carcinosarcoma with panfollicular differentiation (panfollicular carcinosarcoma) and CTNNB1 (beta-catenin) mutation

We present a case of trichoblastic carcinosarcoma with panfollicular differentiation. An 80-year-old man presented with a lesion on the left ear, which had been present for several months. Histopathology revealed a well-demarcated neoplasm in the dermis composed of intimately intermingled malignant epithelial and mesenchymal cells. The epithelial component showed multilineage follicular differentiation toward all of the elements of a normal hair follicle. Molecular analysis revealed identical molecular aberrations in both epithelial and mesenchymal components including CTNNB1 and SUFU mutations. To the best of our knowledge, this is the first report of panfollicular carcinosarcoma and of the presence of a CTNNB1 mutation in trichoblastic carcinosarcoma.

A genomic survey of sarcomas on sun-exposed skin reveals distinctive candidate drivers and potentially targetable mutations

Sarcomas on photodamaged skin vary in prognosis and management, but can display overlapping microscopic and immunophenotypic features. Improved understanding of molecular alterations in these tumors may provide diagnostic and therapeutic insights. We characterized 111 cutaneous sarcomatoid malignancies and their counterparts, including primary cutaneous angiosarcoma (n = 7), atypical fibroxanthoma (AFX) (n = 21), pleomorphic dermal sarcoma (PDS) (n = 17), extracutaneous undifferentiated pleomorphic sarcoma (n = 8), cutaneous leiomyosarcoma (LMS) (n = 5), extracutaneous LMS (n = 9), sarcomatoid squamous cell carcinoma (spindle cell squamous cell carcinoma) (S-SCC) (n = 24), and conventional cutaneous squamous cell carcinoma (SCC) (n = 20), by next-generation sequencing (NGS) using the StrataNGS panel for copy number variations, mutations, and/or fusions in more than 60 cancer-related genes. TP53 mutations were highly recurrent in most groups. Angiosarcoma displayed previously reported MYC amplifications, as well as CCND1 gains. RB1 mutations were relatively restricted to cutaneous LMS. As previously reported, PIK3CA mutations occurred in AFX, whereas RAS activation was more frequent in PDS. CDKN2A mutations were recurrent in AFX and S-SCC, whereas PDS displayed frequent CDKN2A deletion. S-SCC displayed mutational similarity to conventional SCC. BRCA1/2 mutations were specific to tumors with disease progression. In a subset, we detected potential driver events novel to these tumor types: activating mutations in IDH2 (PDS), MAP2K1 (angiosarcoma, PDS), and JAK1 (S-SCC) and copy gains in FGFR1 (angiosarcoma, S-SCC), KIT (AFX), MET (PDS), and PDGFRA (PDS). Our findings confirm and expand the spectrum of known genomic aberrations, including potential targetable drivers, in cutaneous sarcomatoid malignancies. In addition, certain events are relatively specific to particular tumors within this differential diagnosis and hence might be diagnostically informative.

Primary cutaneous carcinosarcoma: clinical, histological, and immunohistochemical analysis of eight cases

BACKGROUND

Cutaneous carcinosarcoma is a rare biphasic tumor comprising malignant epithelial and heterologous mesenchymal elements. Data on the clinical and histopathologic characteristics of this tumor are scarce. The objective of this study was to describe the clinicopathologic and immunohistochemical features of cutaneous carcinosarcoma.

METHODS

A descriptive retrospective study was conducted in a tertiary care hospital from Spain. We reviewed the records of eight patients with cutaneous carcinosarcoma who were diagnosed from 2009 to 2019.

RESULTS

The mean patient age at diagnosis was 72.13 years (range 44-91 years), and there was a male predilection (6 cases). The most common site of cutaneous carcinosarcoma was the head and neck (5 cases). Carcinosarcomas demonstrated variable histopathological and immunohistochemical features. Follow-up was available for 7-8 patients. There were two cases of local recurrence and one case of metastasis. Two patients died from the tumor during the entire follow-up.

CONCLUSIONS

Although the number of cases in this study was limited, our results provide valuable insight into the clinical, histopathologic, and immunohistochemical characteristics of primary cutaneous carcinosarcoma.

Syringocystadenocarcinoma papilliferum associated with atypical stroma: A hitherto undocumented variant of sarcomatoid carcinoma

Carcinosarcomas are biphasic tumors composed of admixed malignant epithelial and mesenchymal components. Numerous terms have been used to name such neoplasms; therefore, terminological confusion is frequent. Most examples of carcinosarcomas are encountered in non-cutaneous sites, with approximately 100 cases of cutaneous carcinosarcomas reported so far in the English literature. Although different theories have been suggested to explain the occurrence of these peculiar neoplasms, histogenetic mechanisms should be better hypothesized depending on each individual case. Even though prognosis tends to be related to the specific components of the lesion, especially the epithelial one, it seems that cases of cutaneous localization usually have a better outcome. We report an exceedingly rare case of syringocystadenocarcinoma papilliferum which showed an atypical stroma with sarcomatoid appearance, and highlight that the terminology used for this spectrum of lesions is disorganized and confusing.

EMT Transition States during Tumor Progression and Metastasis

Epithelial-mesenchymal transition (EMT) is a process in which epithelial cells acquire mesenchymal features. In cancer, EMT is associated with tumor initiation, invasion, metastasis, and resistance to therapy. Recently, it has been demonstrated that EMT is not a binary process, but occurs through distinct cellular states. Here, we review the recent studies that demonstrate the existence of these different EMT states in cancer and the mechanisms regulating their functions. We discuss the different functional characteristics, such as proliferation, propagation, plasticity, invasion, and metastasis associated with the distinct EMT states. We summarize the role of the transcriptional and epigenetic landscapes, gene regulatory network and their surrounding niche in controlling the transition through the different EMT states.

Giant Pendulous Carcinosarcoma - Squamous Cell Carcinoma-Type - of the Leg - A Case Report and Review of the Literature

Cutaneous carcinosarcoma (CCS) is a rare non-melanoma skin cancer with a biphasic growth pattern. A tumour is composed of epithelial and mesenchymal cells that show clonality. In most cases, CCS develops in the head-and-neck region on the chronic sun-exposed skin of males. Here, we describe an 80-year-old female patient who developed a giant, pendulous CCS on the leg. A tumour was surgically removed. We found no evidence of metastatic spread.

Cutaneous Metaplastic Carcinoma: Report of a Case With Sebaceous Differentiation

In this study, a case of a 56-year-old woman with cutaneous metaplastic carcinoma in the neck is reported. It harbored basal cell carcinoma, squamous cell carcinoma, and sebaceous carcinoma, as well as osteosarcoma (with fibroblastic, osteoblastic, aneurysmal bone cyst-like, and chondroblastic patterns). To our knowledge, the literature does not mention sebaceous carcinoma in cutaneous metaplastic carcinoma. Epidemiology and intact mismatch repair proteins of this case support sporadic pathogenesis for this neoplasm. The patient has been followed up for 3 years after surgery with free margins, and no local recurrence or distant metastases have been observed.

Carcinosarcomas and Related Cancers: Tumors Caught in the Act of Epithelial-Mesenchymal Transition

In this review, we outline the biology and management of patients with carcinosarcomas and related malignancies, which are often included under the broader concept of sarcomatoid carcinomas. Carcinosarcomas are unusual tumors that are commonly gynecologic in origin, where they are referred to as malignant mixed Müllerian tumors, but may appear in any anatomic site. Although a variety of hypotheses have been presented as to the biphasic nature of these tumors, carcinosarcomas seem to represent the best example in human cancers of the concept of epithelial-mesenchymal transition (EMT), in which the two parts of the tumor are genomically related to one another, as opposed to the mesenchymal component that represents a second neoplasm or (benign) reactive process. In general, patients with carcinosarcomas fare worse than patients with carcinomas of the same anatomic site. Treatment paradigms for carcinosarcomas generally follow those of carcinomas of the same organ site, except where clinical trials provide more specific options. Agents that block or reverse EMT are worth examination in patients with carcinosarcoma and arguably may be even more effective in carcinomas, given evidence of dependence on EMT to generate successful metastases. Information about EMT may also inform other phase transitions in cancer, such as those between prostate or lung carcinoma and more aggressive tumors with neuroendocrine differentiation.

Lung Sarcomatoid Carcinoma Metastasis to Skin: A Case Report and Review of the Literature

Sarcomatoid carcinoma is a biphasic neoplasm composed of highly complex, intimately admixed malignant epithelial and mesenchymal elements. We herein report a rare case of cutaneous metastasis of pulmonary sarcomatoid carcinoma that contains liposarcomatous, rhabdosarcomatous and chondrosarcomatous heterologous differentiation, and review relevant literatures to lead to a better understanding of this rare but highly aggressive tumor.

Cutaneous Collision Tumor Associated With Porocarcinomatous and Angiosarcomatous Components: A Potential Diagnostic Pitfall

Sarcomatoid eccrine porocarcinoma (SEP) is a very rare malignancy including epithelial and mesenchymal components exhibiting pleomorphic cells, nuclear hyperchromasia, and high mitotic activity in both elements. To date, only 6 cases of this uncommon neoplasm have been reported, corresponding to women over 70 years of age with ulcerated skin lesions. The authors describe the first sarcomatoid eccrine porocarcinoma in a 75-year-old male patient with a right hallux lesion, presenting a collision tumor with a mixed population of epithelial cells and a spindle cell angiosarcomatous mesenchymal component each expressing distinct and nonoverlapping morphologic and immunohistochemical features of epithelial and mesenchymal differentiation.

Trichoblastic carcinosarcoma: an authentic cutaneous carcinosarcoma

We describe a trichoblastic carcinosarcoma on the forehead of a 65-year-old man. This is the fifth case of trichoblastic carcinosarcoma in the literature and the first to be reported from the USA. It was successfully treated with direct excision. Trichoblastic carcinosarcoma should be distinguished from epidermal carcinosarcoma. We believe trichoblastic carcinosarcoma is an authentic carcinosarcoma derived from multiple progenitor cells whereas epidermal carcinosarcomas are derived from a single progenitor cell that undergoes epithelial to mesenchymal transition, and are better considered as sarcomatoid carcinomas.

Identification of Factors Affecting the Success of Next-Generation Sequencing Testing in Solid Tumors

OBJECTIVES

Clinical laboratories are rapidly implementing next-generation sequencing (NGS) tests for mutation analysis, but there are few guidelines regarding sample quality for successful results.

METHODS

We aimed to establish tissue quality parameters for successful NGS in solid tumors and to improve NGS performance.

RESULTS

Analysis of 614 clinical cases tested in 2013 using a 50-gene hotspot mutation panel identified the major cause for unsuccessful NGS analysis was DNA less than 10 ng (91%, 67/74) associated with extremely small and low cellularity samples. High success rates were associated with resection procedures (333/342, 97%) and biopsied tumor larger than 10 mm(2) (77/77, 100%). NGS can be successfully performed on bone specimens processed with formic acid-based decalcification procedures (8/11, 73%). Tumor type and paraffin block age did not affect success. We demonstrated that NGS can be carried out on samples with less than 10 ng DNA. Analysis of 408 cases tested in 2014 using an optimized workflow showed improved NGS success rates from 88% to 95% (387/408) with pronounced improvement among tiny (<10 mm(2)) samples (from 76% to 94%) as well as cytology samples (from 58% to 87%).

CONCLUSIONS

Identifying preanalytical tissue factors allows us to improve NGS performance and to successfully test tumors obtained from minimally invasive procedures.

Wide expression of ZEB1 in sarcomatous component of spindle cell carcinoma of the esophagus

The pathogenesis of sarcomatous component in spindle cell carcinoma (SpCC) of the esophagus is unclear. To investigate the involvement of epithelial-mesenchymal transition (EMT) in sarcomatous differentiation, we performed immunohistochemistry for Slug, Twist, ZEB1, and ZEB2, transcription factors associated with EMT and E-cadherin, in 14 cases of SpCC of the esophagus. In order to verify the neoplastic nature of sarcomatous components, TP53 mutation status and protein expression were examined in each case. Nuclear ZEB1 expression was extensive in the sarcomatous component, greater than invasive front of carcinoma components (P < 0.0001). Membranous E-cadherin expression was mostly lost in sarcomatous cells in all cases (P < 0.0001). The p53 expression pattern was almost concordant between the two areas in all cases. TP53 mutation analysis revealed that seven cases harbored identical mutations in both components. One case had mutations only in the sarcomatous component. It is noteworthy that none of them harbored mutation in exon 5, unlike conventional esophageal squamous cell carcinoma. These findings show that ZEB1 are widely expressed in the sarcomatous area of SpCC of the esophagus, suggesting the involvement of EMT. The avoidance of exon 5 in terms of TP53 mutation may also be a feature of the tumor.

Cutaneous basal cell carcinosarcomas: evidence of clonality and recurrent chromosomal losses

Cutaneous carcinosarcomas are heterogeneous group of tumors composed of malignant epithelial and mesenchymal components. Although mutation analyses have identified clonal changes between these morphologically disparate components in some subtypes of cutaneous carcinosarcoma, few cases have been analyzed thus far. To our knowledge, copy number variations (CNVs) and copy-neutral loss of heterozygosity (CN-LOH) have not been investigated in cutaneous carcinosarcomas. We analyzed 4 carcinosarcomas with basal cell carcinoma and osteosarcomatous components for CNVs/CN-LOH by comparative genomic hybridization/single-nucleotide polymorphism array, TP53 hot spot mutations by polymerase chain reaction and Sanger sequencing, and TP53 genomic rearrangements by fluorescence in situ hybridization. All tumors displayed multiple CNV/CN-LOH events (median, 7.5 per tumor). Three of 4 tumors displayed similar CNV/CN-LOH patterns between the epithelial and mesenchymal components within each tumor, supporting a common clonal origin. Recurrent changes included allelic loss at 9p21 (CDKN2A), 9q (PTCH1), and 17p (TP53). Allelic losses of chromosome 16 including CDH1 (E-cadherin) were present in 2 tumors and were restricted to the sarcomatous component. TP53 mutation analysis revealed an R248L mutation in both epithelial and mesenchymal components of 1 tumor. No TP53 rearrangements were identified. Our findings indicate that basal cell carcinosarcomas harbor CNV/CN-LOH changes similar to conventional basal cell carcinoma, with additional changes including recurrent 9p21 losses and a relatively high burden of copy number changes. In addition, most cutaneous carcinosarcomas show evidence of clonality between epithelial and mesenchymal components.