Clear cell sarcoma of tendons and aponeuroses, and osteoclast-rich tumour of the gastrointestinal tract with features resembling clear cell sarcoma of soft parts: a review and update

Malignant Gastrointestinal Neuroectodermal Tumor (GNET) Mimicking Small Bowel Lymphoma: A Case Report

A malignant gastrointestinal neuroectodermal tumor (GNET) is a rare entity, characterized as a malignant mesenchymal neoplasm occurring exclusively near the gastrointestinal tract, prone to frequent local recurrence and metastasis. Here, we report a case of a 49-year-old male presented with abdominal pain and weight loss. The patient had a remote history of thymic B-cell lymphoma. An abdominal computed tomography (CT) scan revealed a focal wall thickening of the terminal ileum with mesenteric lymphadenopathy, suggestive of lymphoma. A core needle biopsy of the mesenteric node was inconclusive. A right hemicolectomy was subsequently performed. Histologically, abundant multinucleated osteoclast-like giant cells are present. The tumor cells show diffuse strong positivity for S100 and SOX10. EWSR1-ATF1 gene fusion was identified by fluorescence in situ hybridization (FISH), consistent with a diagnosis of GNET. This case emphasizes a diagnostic challenge of a rare malignancy.

A Rare Case of Clear Cell Sarcoma of the Tongue: A Case Report

Clear cell sarcoma (CCS), previously known as soft tissue melanoma due to similarities with melanoma, is a rare and aggressive neoplasm. This tumor predominantly occurs in the lower limbs and rarely affects the tongue, as well as other head and neck locations. To our knowledge, only five cases have been reported in the English literature. CCS presents many similar morphological and immunohistochemical features to those of melanomas, sarcomatoid cell carcinoma, angiomatoid histiocytoma, and Ewing sarcoma, which makes the diagnosis difficult, especially in cases of uncommon locations. The treatment is based on oncological surgery and adjuvant radiation therapy as these tumors show low sensitivity to chemotherapy. This study aimed to report a case of an 88-year-old male patient who presented a large, rapidly growing nodular lesion on the right border of the mobile tongue diagnosed with CCS of the tongue.

The current management of clear cell sarcoma

Clear cell sarcoma (CCS) is a rare melanocytic soft tissue sarcoma with a high propensity for lymphatic metastasis and poor prognosis. It is characterized by the translocation of t (12;22), resulting in the rearrangement of the EWSR1 gene and overexpression of MET. Despite improvements in the diagnosis and treatment of soft tissue sarcomas, the management of CCSs remains challenging owing to their rarity, unique biological behaviour and limited understanding of their molecular pathogenesis. The standard treatment for localized CCSs is surgical excision with negative margins. However, there is an ongoing debate regarding the role of adjuvant chemotherapy, radiotherapy and lymphadenectomy in the management of this disease. CCSs are usually resistant to conventional chemotherapy. Targeted therapies, such as sunitinib and MET inhibitors, may provide promising results. Immunotherapy, particularly immune checkpoint inhibitors, is currently under investigation as a potential treatment option for CCSs. Further research is needed to better understand the biology of CCSs and develop effective therapeutic strategies. The purpose of this review is to provide a comprehensive overview of current knowledge and advances in the diagnosis and treatment of CCSs.

Functional genomics of human clear cell sarcoma: genomic, transcriptomic and chemical biology landscape for clear cell sarcoma

BACKGROUND

Systemic therapy for metastatic clear cell sarcoma (CCS) bearing EWSR1-CREB1/ATF1 fusions remains an unmet clinical need in children, adolescents, and young adults.

METHODS

To identify key signaling pathway vulnerabilities in CCS, a multi-pronged approach was taken: (i) genomic and transcriptomic landscape analysis, (ii) integrated chemical biology interrogations, (iii) development of CREB1/ATF1 inhibitors, and (iv) antibody-drug conjugate testing (ADC). The first approach encompassed DNA exome and RNA deep sequencing of the largest human CCS cohort yet reported consisting of 47 patient tumor samples and 8 cell lines.

RESULTS

Sequencing revealed recurrent mutations in cell cycle checkpoint, DNA double-strand break repair or DNA mismatch repair genes, with a correspondingly low to intermediate tumor mutational burden. DNA multi-copy gains with corresponding high RNA expression were observed in CCS tumor subsets. CCS cell lines responded to the HER3 ADC patritumab deruxtecan in a dose-dependent manner in vitro, with impaired long term cell viability.

CONCLUSION

These studies of the genomic, transcriptomic and chemical biology landscape represent a resource 'atlas' for the field of CCS investigation and drug development. CHK inhibitors are identified as having potential relevance, CREB1 inhibitors non-dependence of CCS on CREB1 activity was established, and the potential utility of HER3 ADC being used in CCS is found.

"E-MGNET": Extra-Enteric Malignant Gastrointestinal Neuroectodermal Tumor- A Clinicopathological and Molecular Genetic Study of 11 Cases

Malignant gastrointestinal neuroectodermal tumors (MGNET), also known as "gastrointestinal clear cell sarcoma-like tumor", are very rare, aggressive sarcomas characterized by enteric location, distinctive pathologic features, and EWSR1/FUS::ATF1/CREB1 fusions. Despite identical genetics, the clinicopathologic features of MGNET are otherwise quite different from clear cell sarcoma of soft parts (CCS). Only exceptional extra-enteric MGNET (E-MGNET) have been reported. We report a series of 11 E-MGNET, the largest to date. Cases diagnosed as MGNET and occurring in non-intestinal locations were retrieved. Clinical follow-up was obtained. The tumors occurred in 3 males and 8 females (14-70 years of age, median 33 years) and involved the soft tissues of the neck (3), shoulder (1), buttock (2), orbit (1), and tongue/parapharyngeal space (1), the urinary bladder (1) and the falciform ligament/liver (1). Tumors showed morphologic features of enteric MGNET (small, relatively uniform, round to ovoid cells with round, regular nuclei containing small nucleoli, growing in multinodular and vaguely lobular patterns, with solid, pseudoalveolar and pseudopapillary architecture). Immunohistochemical results were: S100 protein (11/11), SOX10 (11/11), synaptophysin (3/10), CD56 (7/9), CD117 (3/9), DOG1 (0/4), ALK (4/8), chromogranin A (0/10), HMB45 (0/11), Melan-A (0/11), tyrosinase (0/4), MiTF (0/11). NGS results were: EWSR1::ATF1 (7 cases), EWSR1::CREB1 (3 cases) and EWSR1::PBX1 (1 case). The EWSR1::PBX1-positive tumor was similar to other cases, including osteoclast-like giant cells, and negative for myoepithelial markers. Clinical follow-up (range: 10 to 70 months; median 34 months) showed 4 patients dead of disease (10.5, 12, 25 and 64 months after diagnosis), 1 patient alive with extensive metastases (43 months after diagnosis), 1 patient alive with persistent local disease (11 months after diagnosis), and 4 alive without disease (10, 47, 53 and 70 months after diagnosis). One case is too recent for follow-up. The clinicopathologic and molecular genetic features of rare E-MGNET are essentially identical to those occurring in intestinal locations. Otherwise-typical E-MGNET may harbor EWSR1::PBX1, a finding previously unreported in this tumor type. As in enteric locations, the behavior of E-MGNET is aggressive, with metastases and/or death from disease in at least 50% of patients. E-MGNET should be distinguished from CCS and other tumors with similar fusions. ALK expression appears to be a common feature of tumors harboring EWSR1/FUS::ATF1/CREB1 fusion but is unlikely to predict therapeutic response to ALK inhibition. Future advances in our understanding of these unusual tumors will hopefully lead to improved nomenclature.

Clear cell sarcoma: state-of-the art and perspectives

INTRODUCTION

Clear cell sarcoma (CCS) is an ultrarare soft tissue sarcoma (STS) with a poor prognosis due to its propensity to metastasize and its low chemosensitivity. The standard treatment of localized CCS consists of wide surgical excision with or without additive radiotherapy. However, unresectable CCS is generally treated with conventional systemic therapies available for treatment of STS despite the weak scientific evidence to support its use.

AREAS COVERED

In this review, we discuss the clinicopathologic characteristics of CSS, as well as the current treatment landscape and future therapeutic approaches.

EXPERT OPINION

The current treatment strategy of advanced CCSs, based on STSs regimens, shows a lack of effective options. Combination therapiesin particular, the association of immunotherapy and TKIs, represent a promising approach. Translational studies are needed in order to decipher the regulatory mechanisms involved in the oncogenesis of this ultrarare sarcoma and identify potential molecular targets.

Clear cell sarcoma of soft tissue with plasmacytoid morphology: A rare case report

RATIONALE

Clear cell sarcoma of soft tissue (CCSST) is a rare malignant tumor that occurs in the extremities of young adults. CCSST has been documented to have atypical histopathological features, such as epidermotropism or myxoid differentiation, which may set pitfalls in the differential diagnosis. We report a case of CCSST with plasmacytoid morphology which has never been described.

PATIENT CONCERNS

A 15-year-old male, presented with a 5-cm mass in his left inguinal area.

DIAGNOSIS

Positron emission tomography-computed tomography examination showed nodules in the left groin and the lung, the latter was considered metastasis. A core needle biopsy with the diagnosis of CCSST with plasmacytoid morphology was made according to histology, immunostaining, and molecular analysis.

INTERVENTIONS

The patient received chemotherapy of doxorubicin and ifosfamide.

OUTCOMES

The patient failed to respond to the standard chemotherapy and deceased twelve months after diagnosis.

LESSONS

This special case of CCSST with plasmacytoid features demonstrated a morphological variation never been documented and may easily lead to misdiagnosis. For such cases, molecular analysis is essential to provide solid evidence for accurate diagnosis.

Systemic treatment of malignant gastrointestinal neuroectodermal tumour after childhood neuroblastoma: chemotherapy in malignant gastrointestinal neuroectodermal tumour

Malignant gastrointestinal neuroectodermal tumour is an extremely rare neoplasm that arises in the wall of the small bowel, stomach or large bowel in young-aged and middle-aged adults. Histologically, it is generally characterized by monomorphic cells with clear cytoplasma, S-100 protein expression, and EWSR1 gene translocation. To the best of our knowledge, we describe for the first time, the case of a young woman with a diagnosis of metastatic gastrointestinal neuroectodermal tumour arising from ileum, who had a childhood adrenal neuroblastoma with liver, bone and lymph nodes metastasis, treated with four cycles of chemotherapy with the schedule CADO-CVP (CADO: cyclophosphamide 300 mg/m/day on days 1-5, vincristine 1,5 mg/m/day on days 1 and 5, and doxorubicin 60 mg/m/day on day 5; CVP: cisplatin 40 mg/m/day on days 1-5 and etoposide 100 mg/m/day on days 1-5) followed by right adrenal, kidney, lymph nodes and liver lesion resection, conditioning chemotherapy (melphalan-carmustine-teniposide), stem cells autologous transplantation and consecutively radiotherapy on the spine (T9 to L3) for a total of 30 Gy. For the second diagnosis of gastrointestinal neuroectodermal tumour with liver metastasis, she underwent ileal tumour resection and platinum-anthracycline based chemotherapy with initial shrinkage of liver metastasis. Unfortunately, despite the initial response and the following delivered therapies, she died for rapid progressive disease. Taking into account the late effects of past therapeutic modalities, a long-term surveillance of young child treated for neuroblastoma, is required to appreciate their overall risks of second malignancies.

Malignant Gastrointestinal Neuroectodermal Tumor: Clinicopathologic, Immunohistochemical, and Molecular Analysis of 19 Cases

A malignant gastrointestinal neuroectodermal tumor (GNET) is rare, and it is therefore yet to be completely understood. This study aimed to present the clinicopathologic features of GNET, including treatment information. We included 19 patients with GNET with a mean tumor size of 4.2 cm. The most common site of tumor origin was the small intestine (57.9%), followed by the stomach (15.8%), colon (10.5%), ileocecal junction (5.3%), lower esophagus (5.3%), and anal canal (5.3%). Microscopically, the tumors were composed of epithelioid cells with eosinophilic or clear cytoplasm arranged in nest, sheet-like, papillary, or pseudoalveolar patterns and/or spindle tumor cells with eosinophilic cytoplasm arranged in a fascicular pattern. Immunohistochemically, the tumor cells stained positively for S100 (19/19,100%), SOX10 (14/15, 93.3%), vimentin (17/17, 100%), synaptophysin (Syn) (7/17, 41.2%), CD56 (4/13, 30.8%), CD99 (1/5, 20%), and CD117 (1/15, 6.7%), and negatively for HMB45, Melan A, DOG1, CD34, AE1/AE3, CAM5.2, chromogranin A, smooth muscle actin, and desmin. In total, 14/15 (93.3%) cases showed split Ewing sarcoma breakpoint region 1 gene (EWSR1) signals consistent with a chromosomal translocation involving EWSR1. Within a mean follow-up of 29.7 months (range: 3 to 63 mo), 2/15 (13.3%) patients died of disease, 5 (33.3%) were alive with disease, and 8 (53.3%) had no evidence of disease. Two and 1 patients showed partial response to apatinib and anlotinib, respectively. In conclusion, GNET has distinctive morphologic, immunohistochemical, and molecular genetic features and should be distinguished from other gastrointestinal tract malignancies. Apatinib and anlotinib might be effective for the treatment of advanced GNET and could prolong patient survival.

Primary Intracranial Mesenchymal Tumor with EWSR1-CREM Gene Fusion: A Case Report and Literature Review

BACKGROUND

The prevalence of gene translocation in some mesenchymal tumors can be used as highly specific molecular diagnostic markers in clinic and pathology. EWSR1 is a partner gene in a large, diverse range of mesenchymal tumors.

CASE DESCRIPTION

This paper describes the case of a 31-year-old man who was diagnosed with a primary intracranial mesenchymal tumor with EWSR1-CREM gene fusion and eventually returned to a normal live with no signs of tumor recurrence or metastasis after treatment, including surgery therapy, radiotherapy, and 6 cycles of vincristine-doxorubicin-cyclophosphamide chemotherapy, even though the classification and grade of the tumor are still controversial.

CONCLUSIONS

This case is a novel entity of intracranial mesenchymal neoplasm with EWSR1-CREM gene fusion which was confirmed by histopathology, molecular pathology, and next-generation sequencing (NGS). The literature review shows only 5 cases of intracranial tumor harboring EWSR1-CREM gene fusion with similar features. With the further application of molecular pathology and NGS in clinical practice, there will be more intracranial mesenchymal tumor cases with EWSR1-CREM gene fusion found in the future, which may lead to further understanding of the diagnosis and clinical features of this neoplasm.

Primary Cutaneous Clear Cell Sarcoma, Clinical Outcome With Sentinel Lymph Nodes Status

OBJECTIVES

Primary cutaneous clear cell sarcoma (PCS) is a rare malignancy and difficult to differentiate from melanoma. We investigated factors influencing survival and recurrence.

METHODS

An institutional cancer registry and literature search were used for a retrospective study. Only clear cell sarcoma cases with a primary site of skin and subcutaneous tissue were included. Kaplan-Meier and Cox regression analyses were used to assess survival time and hazard ratios.

RESULTS

Three eligible cases were identified at our institution. In addition, the PubMed and Google Scholar reviews identified 1,878 items, with 23 patients with PCS. The median age was 25 years with 62% female. The tumors ranged in size from 0.4 to 4.5 cm. Cytogenetics showed t(12;22)(q13;q12) in all cases and a unique variant of t(2;22)(q32.3;q12) in one case. Surgery was the most common treatment, followed by chemotherapy/radiation. PCS recurred in 46% of patients with a median relapse-free survival time of 15 months. Only two known PCS-related mortalities were recorded, at 38 and 60 months following initial diagnosis. Smaller tumor size and negative sentinel lymph node biopsy (SLNB) status were significantly associated with a better disease-free survival.

CONCLUSIONS

Tumor size and SLNB status influence PCS survival and recurrence. More research is needed due to the rarity of this disease.

Clear Cell Sarcoma of the Foot in an 18-Year-Old Female

We report a case of an 18-year-old female without a relevant medical history who presented with an 8-month history of a left foot mass. It started as a small nodule that progressively increased in size over time. The mass then became ulcerative with foul-smelling discharge. There was no palpable left inguinal or other lymph nodes upon physical examination. Histological examination of the biopsy confirmed a diagnosis of clear cell sarcoma. Clear cell sarcoma is a rare soft tissue neoplasm. However, early diagnosis is crucial to prevent metastasis and worsened prognosis. Clear cell sarcoma has an extremely poor prognosis once metastasis occurs, and to the best of our knowledge, only fewer than 100 cases have been reported in the literature.

Soft tissue tumor diagnosis: A three prong approach utilizing pattern analysis, immunocytochemistry, and molecular diagnostics

Tissue diagnosis of a soft tissue neoplasm is of paramount importance for the development of an appropriate treatment plan. Biopsy technique including approach and biopsy method is important to the success of diagnosis and subsequent treatment. Histologic and cytologic diagnoses are difficult and complicated by the large number of soft tissue lesions described, distinctly different biopotential for morphologically similar lesions, often small biopsy specimen size, and the generally limited experience many pathologists have in the diagnosis of soft tissue neoplasms. While utilized less frequently than core-needle biopsies, fine-needle aspiration is a valuable initial approach for the classification of soft tissue neoplasms. The combination of pattern based morphologic analysis, immunohistochemistry, and molecular diagnostics represents a utilitarian and generally successful approach for the diagnosis of soft tissue lesions.

Prognostic analysis of surgically treated clear cell sarcoma: an analysis of a rare tumor from a single center

BACKGROUND

The objective of this retrospective study was to evaluate the prognostic value of various factors in clear cell sarcoma patients after radical surgery.

METHODS

Forty-two clear cell sarcoma patients from August 2006 to March 2018 were included in the study. Curves of disease-free survival and overall survival were calculated using the Kaplan-Meier method, and univariate and multivariate analyses of various prognostic factors were performed using a Cox proportional hazard regression model. Laboratory test of peripheral blood was recorded before surgery. The optimal cutoff value of systemic inflammatory markers was defined by receiver-operating curve analysis.

RESULTS

The 5-year DFS and 5-year OS rate were 22% and 46%, respectively. The median DFS and OS times were 12 and 41.5 months, respectively. In univariate analysis, there was a significant association between shorter DFS and tumor size larger than 5 cm (p = 0.0043), positive surgical margin (p = 0.0233), and the neutrophil-to-lymphocyte ratio (NLR) higher than 2.73 (p = 0.0009). Furthermore, we observed a significant association between shorter OS and tumor size larger than 5 cm (p = 0.0075), positive surgical margin (p = 0.0101), NLR higher than 2.73 (p = 0.0126), the platelet-to-lymphocyte ratio (PLR) higher than 103.89 (p = 0.0147) and the lymphocyte-to-monocyte ratio (LMR) lower than 4.2 (p = 0.0445). A multivariate analysis demonstrated that the surgical margin (p = 0.013) and NLR (p = 0.001) were significantly associated with DFS. Tumor size (p = 0.010) and NLR (p = 0.013) were independent prognostic factors for OS.

CONCLUSIONS

This study had the second largest sample around the world and preoperative NLR may be a useful prognostic factor in CCS patients after radical surgery.

Mesenchymal Tumors with EWSR1 Gene Rearrangements

Among the various genes that can be rearranged in soft tissue neoplasms associated with nonrandom chromosomal translocations, EWSR1 is the most frequent one to partner with other genes to generate recurrent fusion genes. This leads to a spectrum of clinically and pathologically diverse mesenchymal and nonmesenchymal neoplasms, variably manifesting as small round cell, spindle cell, clear cell or adipocytic tumors, or tumors with distinctive myxoid stroma. This review summarizes the growing list of mesenchymal neoplasms that are associated with EWSR1 gene rearrangements.

Primary malignant gastrointestinal neuroectodermal tumor occurring in the ileum with intra-abdominal granulomatous nodules: A case report and review of the literature

Malignant gastrointestinal neuroectodermal tumors (GNETs) are rare aggressive malignant neoplasms that exclusively occur within the wall of the gastrointestinal tract. The GNET was first described as an ‘osteoclast-rich tumor of the gastrointestinal tract with features resembling clear cell sarcoma (CCS) of soft parts’ in 2003. Although the GNET shares certain histological features with CCS, it is characterized by a lack of melanocytic differentiation and the presence of non-tumoral osteoclast-like giant cells (OLGCs). The present study reports a case of a GNET of the ileum with intra-abdominal granulomatous nodules, an uncommon accompanying finding, and summarizes the current literature. A 30-year-old woman presented with the symptoms of intestinal obstruction, and a mass was found within the ileum wall. Multiple grey-white nodules were found adhering to the omentum and serosa of the ileum. Histologically, the tumor was located in the muscularis propria and infiltrated the mucosa and the serosa. Tumor cells presented with oval or polygonal nuclei and prominent nucleoli, and were predominantly arranged in nested and pseudopapillary patterns, with the presence of cluster of differentiation (CD)68-positive, scattered OLGC. Immunohistochemically, it was determined that the tumor cells expressed Vimentin, CD56, S-100 and transcription factor SOX-10, while being negative for pan-cytokeratin, cytokeratin (CK)7, CK20, synaptophysin, chromogranin-A, CD117, anoctamin-1, CD34, human melanoma black-45, Melan-A, smooth muscle actin, CD3 and CD20 expression. Ewing sarcoma breakpoint region 1 gene rearrangement was identified by fluorescence in situ hybridization analysis. Ultrastructurally, no typical melanosomes were identified. In addition, the intra-abdominal grey-white nodules were microscopically identified as chronic granulomatous inflammation. The patient received four cycles of adjuvant chemotherapy following routine tumor resection. Due to its rarity and histological similarity with other neoplasms, unfamiliarity with the features of GNETs by surgical pathologists can easily lead to a misdiagnosis. Therefore, comprehensive assessments, including morphology and ancillary studies, are required for an accurate diagnosis of GNET.

Clear cell sarcoma-A review

Clear cell sarcoma (CCS) previously known as malignant melanoma (MM) of the soft tissue, although, similar in morphology to MM, contemporary histopathologic and cytogenetic techniques have made this diagnosis obsolete, as it is now possible to distinguish between CCS and MM. CCS is often diagnosed in young adults with median age of 25 years. Overall mortality is generally poor, and the 5-year survival is between 40 and 60%. Hence, early diagnosis and radical surgery are key in the treatment of this extremely rare malignancy of the soft tissue comprising only about 1% of all sarcomas. This article present an overview of this rare malignancy.

Primary clear cell sarcoma of the tongue and surgical reconstruction: About a rare case report

Clear cell sarcomas (SCC), also called "soft-tissue melanoma", are rare and aggressive tumors that preferentially affect the lower limbs (tendons and fasciae) and which have also been described in head and neck localizations. Their clinical and immunohistochemical mimicry with melanoma makes it difficult to diagnose sarcomas. SCC treatment is mainly focused on large-scale resection surgery with adjuvant radiotherapy because of their low chemo-sensitivity and extreme lymphophilia. In case of head and neck localization, these treatments may lead to function and aesthetic sequelae thus requiring the use of modern techniques of reconstructive surgery. The authors describe the diagnosis, treatment and follow-up of large lingual SCC case using a DIEP free flap reconstruction according to an original technique developed in the department. Given the characteristics of patients with SCC (a high proportion of women between 20 and 40 years old) and its inherent qualities (low morbidity of the donor site, volume delivered and excellent plasticity), the fascio-cutaneous free flap type "DIEP" "taken according to the design of the" Cathedral triptych seems to be a viable choice among the range of reconstruction solutions.

Detection of specific gene rearrangements by fluorescence in situ hybridization in 16 cases of clear cell sarcoma of soft tissue and 6 cases of clear cell sarcoma-like gastrointestinal tumor

Background

Clear cell sarcoma of soft tissue (CCSST) and clear cell sarcoma-like gastrointestinal tumor (CCSLGT) are malignant mesenchymal tumors that share some pathological features, but they also have several different characteristics. They are well known to express chimeric fusions of Ewing sarcoma breakpoint region 1 (EWSR1) and cAMP response element-binding protein (CREB) family members; namely, EWSR1-activating transcription factor 1 (ATF1) and EWSR1-CREB1. In addition, recent studies have suggested the presence of other fusions.

Methods

We used fluorescence in situ hybridization to detect specific rearrangements including EWSR1, ATF1, CREB1, and cAMP response element modulator (CREM) in 16 CCSST and 6 CCSLGT cases. We also used reverse transcription polymerase chain reaction (RT-PCR) to detect specific chimeric fusions of EWSR1-ATF1 and EWSR1-CREB1 using fresh tumor samples in available cases.

Results

A total of 15 of 16 CCSST cases (93.8%) had EWSR1 rearrangement, of which 11 (68.8%) also had ATF1 rearrangement, suggestive of the presence of EWSR1-ATF1 fusions. One CCSST case (6.3%) was found to have EWSR1 and CREM rearrangements, and 4 of 6 CCSLGT cases (66.7%) had EWSR1 rearrangement, of which 2 (33.3%) showed ATF1 rearrangement and the other 2 cases (33.3%) showed CREB1 rearrangement. These cases most likely had EWSR1-ATF1 and EWSR1-CREB1 fusions, respectively. RT-PCR was performed in 8 available cases, including 6 CCSSTs and 2 CCSLGTs. All CCSSTs showed EWSR1-ATF1 fusions. Among the 2 CCSLGT cases, one had EWSR1-ATF1 fusion and the other had EWSR1-CREB1 fusion.

Conclusions

Rearrangements of EWSR1 and ATF1 or EWSR1-ATF1 fusion were predominantly found in CCSST, whereas those of EWSR1 and CREB1 or EWSR1-CREB1 tended to be detected in CCSLGT. A novel CREM fusion was also detected in a few cases of CCSST and CCSLGT. The cases in which EWSR1 rearrangement was detected without definitive partner genes should be considered for the presence of CREM rearrangement.

Successful Surgical Treatment of a Recurrent Esophageal Malignant Gastrointestinal Neuroectodermal Tumor

Malignant gastrointestinal neuroectodermal tumor (GNET) is a very rare disease entity, especially in the esophagus. The diagnosis of GNET is based on histologic, immunohistochemical, and genetic findings. The choice of treatment is complete resection, and further treatment options can be considered. Herein, we describe a case of successful surgical treatment of a 23-year-old man with recurrent malignant esophageal GNET.

Neural and neurogenic tumours of the gastroenteropancreaticobiliary tract

Neural lesions occur uncommonly in the gastroenteropancreaticobiliary tract. However, due to the growing number of screening colonoscopy procedures, polypoid neural lesions of the colon are being recognised increasingly and range from benign tumours to high-grade malignant neoplasms. Morphological variability of neural tumours can be wide, although some entities share pathological features, and, as such, these lesions can be diagnostically challenging. We review the spectrum of pathology of neural tumours in the gastroenteropancreaticobiliary tract, with the goal of providing a practical approach for practising surgical pathologists.

Imprint cytology of clear cell sarcoma-like tumor of the gastrointestinal tract in the small intestine: A case report

Clear cell sarcoma-like tumor of the gastrointestinal tract (CCSLGT) is an extremely rare malignant neoplasm in the digestive tract. Its cytomorphologic features have never previously been reported. Here, we describe a case of CCSLGT, including its cytologic examination findings. A 47-year-old woman presented with a mass in the small intestine, which was resected and sent for imprint cytology. Imprint smears revealed tumor cells with light eosinophilic or clear cytoplasm in a necrotic background. Many of the tumor cells were arranged in a perivascular growth with a pseudopapillary formation, and there were some non-neoplastic osteoclast-like giant cells. Histological examination revealed solid nests and a pseudopapillary pattern of the tumor cells with clear or pale eosinophilic cytoplasm and large nuclei with small nucleoli. Immunohistochemistry showed positive for vimentin, S-100, and SOX-10, and negative for SMA, c-KIT, cytokeratin, HMB-45, and MelanA. The EWSR1 gene split signal was detected by reverse transcriptase fluorescence in situ hybridization, and EWSR1-CREB1 gene fusion was indicated by reverse transcriptase polymerase chain reaction analysis. From these findings, we diagnosed the tumor as CCSLGT. To best of our knowledge, this is the first description of the imprint cytology features of CCSLGT.

Malignant Gastrointestinal Neuroectodermal Tumor: a Unique Rare Neoplasm

Malignant gastrointestinal neuroectodermal tumor (GNET) is a rare malignant tumor. It is also referred to as clear cell sarcoma-like gastrointestinal tumor (CCSLGT). It is an aggressive tumor with a high rate of local recurrence, metastases, and early death from disease. Its pathogenesis is not known. It shows evidence of neural differentiation and lacks immunohistochemical and ultrastructural evidence of melanocytic differentiation. It needs to be distinguished from various mimickers owing to its aggressive course. Herein, we report a case of GNET in a 55-year-old female patient.

Multiple clear-cell sarcomas of small intestine with parotid gland metastasis: A case report

Clear-cell sarcoma is a rare, malignant soft tissue tumor that displays melanocytic differentiation with a distinct molecular profile. It is rarely localized in the gastrointestinal tract. Herein we reported a case of multiple synchronous clear-cell sarcomas of the gastrointestinal tract with parotid gland metastasis. A 51-year-old male patient presented with a growing painless mass under the right ear. A preoperative positron emission tomography/computed tomography showed multiple intestinal masses and a mass in the right parotid with increased glucose uptake, and he underwent operative treatment with resection of three tumors in the jejunum and ileum and then received a right parotidectomy. Postoperative pathological examination showed that cells in the intestinal tumor were consistent with clear-cell sarcoma of the gastrointestinal tract, and the malignant cells in the parotid gland were similar to the intestinal tumor. Immunohistochemical studies revealed positive expression of HMB-45, Melan-A, and S-100. EWSR1 gene fusion transcripts were undetectable by fluorescence in situ hybridization.

Cytohistological and immunohistochemical characteristics of spindle-shaped mesenchymal neoplasms occurring in the gastrointestinal tract

The purpose of the present review is to analyze the cytohistological and immunohistochemical characteristics of spindle-shaped mesenchymal gastrointestinal neoplams (MGNs), a group of unusual neoplastic conditions with different biological behavior. These tumors exhibit clinical pictures strictly related to the site of origin and dimensions, even if they appear generally with an intramural localization. This latter point may suggest an useful application of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), mainly followed by the cell-block procedure (CBP) in the differential diagnostic approach. First of all, we discuss the most common entity of MGNs represented by gastrointestinal stromal tumors (GISTs), analyzing the morphologic characteristics and stressing the strength of immunohistochemical algorithm for diagnostic purposes. Successively, we have reported the less common group of spindle-shaped MGNs comprehensive of those arising elsewhere the soft tissues, such as leiomyomas, leiomyosarcomas, schwannomas, inflammatory myofibroblastic tumor and intra-abdominal desmoid fibromatosis. Finally, very uncommon spindle-shaped MGNs, like clear cell, follicular dendritic cell, undifferentiated pleomorphic and radiation-induced sarcomas as well as spindle cell dedifferentiated liposarcomas, have been briefly mentioned.

Simultaneous Clear Cell Sarcomas of the Duodenum and Jejunum

Clear cell sarcoma (CCS) is an uncommon tumor that usually presents as an extremity mass but can rarely manifest as a gastrointestinal tumor with a diverse spectrum of symptoms, most commonly related to a mass effect or ulceration. Herein we report a case in which two separate tumors, one in the duodenum and the other in the jejunum, present concurrently. The subject presented with symptomatic anemia and underwent imaging and endoscopic studies that culminated in the discovery of the two lesions. He subsequently underwent operative treatment with resection of both tumors and made an unremarkable recovery. The resection specimen consisted of two separate clear cell sarcomas with negative margins. Under microscopic evaluation, they demonstrated nested growths of epithelioid cells with scattered spindled cells infiltrating the enteric wall. The neoplastic cells were positive for S100 with scattered expression of Melan A. Florescence in situ hybridization revealed a translocation at the EWRS1 locus. He was disease-free for 30 months following the procedure; then he developed a rapidly progressing metastatic disease with subsequent death 4 months later.

Diagnostically Challenging Epithelioid Soft Tissue Tumors

In this article, we focus on the histologic features, differential diagnosis, and potential pitfalls in the diagnosis of epithelioid sarcoma, alveolar soft part sarcoma, clear-cell sarcoma, ossifying fibromyxoid tumor, and malignant extrarenal rhabdoid tumor. Numerous other soft tissue tumors also may have epithelioid variants or epithelioid features. Examples include epithelioid angiosarcoma, epithelioid malignant peripheral nerve sheath tumor, epithelioid gastrointestinal stromal tumor, and perivascular epithelioid cell tumor, among others.

Gross examination and reporting of soft tissue tumours: evaluation of compliance with the UK Royal College of Pathologists soft tissue sarcoma dataset

Aims

Soft tissue tumours are a heterogeneous group of neoplasms that can arise at almost every anatomical site. As they often show similar clinical and radiological findings, histology is the definitive diagnostic method and it is crucial that the surgical pathology report contains accurate, useful information for management and prognostication. The soft tissue sarcoma minimum dataset produced by the Royal College of Pathologists in the UK outlines a structure for handling and reporting soft tissue tumours, including the core data required, and aiding pathologists in forming a consistent reporting approach.

Methods

We assessed the information in surgical pathology reports for soft tissue lesions at a tertiary soft tissue centre, in 1 year prior to the development of this dataset, and 1 year after its release, to audit the comparative adequacy of macroscopic and microscopic information provided, and to assess for differences in reporting since the advent of routine ancillary molecular diagnostic testing.

Results and conclusions

We found that while essential information was always included in reports, more specific details contributing to better quality reports such as more detailed macroscopic descriptions and a higher proportion of clinical summaries with radiological correlation were included in 2011 than 2006, despite increasing workload. Specimen handling, particularly of core biopsies, was also improved, reflecting the increasing need to conserve the maximum amount of patient material for molecular investigations.

[Gastro-intestinal neuroectodermal tumor (GNET): A case report of a small intestine tumor with hepatic metastases]

The gastro-intestinal neuroectodermal tumor (GNET) is a rare sarcoma of the digestive tract, which was recently recognised. The knowledge of the morphological, immunohistochemical and molecular diagnostic criteria is necessary to not mistake it for the metastasis of a melanoma or for another sarcoma of the digestive tract as the gastro-intestinal clear cells sarcoma or the malignant peripheral nervous system tumor (MPNST). We report the case of a 41-year-old patient with a GNET of the small intestine with hepatic metastasis. The histological examination showed a diffuse proliferation of epithelioid cells, which only express PS100. The presence EWSR1-ATF1 gene fusions with any melanocytic differentiation leads to the diagnosis of GNET.

The New Kids on the Block: Recently Characterized Soft Tissue Tumors

Soft tissue pathology is a rapidly changing subspecialty. New entities are described relatively often, and new molecular findings for soft tissue tumors are reported in the literature almost every month. This article summarizes the major features and diagnostic approach to several recently characterized entities: superficial CD34-positive fibroblastic tumor, fibrosarcoma-like lipomatous neoplasm, angiofibroma of soft tissue, low-grade sinonasal sarcoma with neural and myogenic features, malignant gastrointestinal neuroectodermal tumor, hemosiderotic fibrolipomatous tumor, and epithelioid inflammatory myofibroblastic sarcoma. Additionally, the article also provides a summary table of recent molecular findings in soft tissue tumors.

An unusual association of malignant gastrointestinal neuroectodermal tumor (clear cell sarcoma-like) and Ewing sarcoma

Very recently a new designation of "Malignant Neuroectodermal Gastrointestinal Tumor" has been proposed for an aggressive form of neuroectodermal tumor with features similar to that of Clear Cell Sarcoma of Soft Tissue, however without a melanocytic differentiation. Also known as "clear cell sarcoma-like tumors of the gastrointestinal tract", these tumors show some features strongly suggesting an origin from a gastrointestinal neuroectodermal precursor cell unable to differentiate along the melanocytic lineage. They occur mainly in young and middle-aged adults, and have a poor prognosis with a high rate of liver and lymphnode metastases. Histologically they are composed of epithelioid or oval-to spindle cells with a sheet-like or nested pattern of growth, strongly positive for neural markers (S-100, SOX10, and vimentin) and negative for the melanocytic ones. EWSR1 gene rearrangements including EWSR1-ATF1 or EWSR1-CREB1 GENE fusions are typically assessed in these tumors. Here we report a case of malignant neuroectodermal gastrointestinal tumor which immunophenotypically unusually expressed FLI-1, occurring in a 29-year-old man with a previous medical history of Ewing sarcoma. We finally suggest that this case might be a further evidence of a link between these two entities.

Malignant gastrointestinal neuroectodermal tumor: A case report and review of the literature

Malignant gastrointestinal neuroectodermal tumor (GNET) is a rare soft tissue sarcoma, previously referred to as clear cell sarcoma-like gastrointestinal tumor (CCSLGT) and also commonly reported in the literature as clear cell sarcoma of the gastrointestinal tract (CCS-GI). The current study reports a case of GNET arising in the stomach of a 17-year-old male, who presented with symptoms of fatigue, anemia and low temperature. Examination with positron emission tomography-computed tomography revealed a soft tissue mass in the gastric antrum. Subsequently, radical distal gastric resection was performed, and the mass measured 6.0×4.0×3.5 cm³. Histopathological analysis revealed that the tumor cells were arranged in nests and focally formed fascicular, pseudopapillary, pseudoalveolar and rosette-like growth patterns. Osteoclast-like giant cells were also observed. Immunohistochemically, the tumor cells were positive for S-100 protein, vimentin and BCL-2, and negative for HMB45, Melan-A, CD117, CD34 and CD99. Additionally, the osteoclast-like giant cells were positive for CD68. Fluorescence in situ hybridization demonstrated EWSR1 gene rearrangement. After 10 months of follow-up, no evidence of recurrence or metastasis was observed. As GNET is currently classified differently and under various names in the literature, the information provided by this case study and review is predicted to be useful towards the accurate diagnosis, treatment and prognosis of this rare tumor type.

Clear Cell Sarcoma–Like Tumor of the Gastrointestinal Tract

Clear cell sarcoma is a rare tumor classically associated with tendons and aponeuroses of lower extremities of young adults and has a distinctive histopathologic and molecular profile. It has been rarely described in other locations other than soft tissues, including the gastrointestinal tract. Herein we report a case of clear cell sarcoma of gastrointestinal tract arising in the ileum, which is rich in osteoclast-like giant cells with a review of the literature.

Malignant melanoma of soft parts with osteoclast-rich giant cells: A rare tumour of the jejunum

Malignant melanoma of soft parts (MMSP), first described by Franz M. Enzinger, is a rare tumour of unknown cell origin. We describe a case of a 45-year-old male who presented with a one-year history of abdominal pain, weakness, and anaemia. Computerised tomography enteroclysis showed a mass in the jejunum that was suggestive of a gastrointestinal stromal tumour. An ulceroinfiltrative lesion measuring 6.5 x 4 x 2cm was identified. Microscopy revealed typical features of MMSP with numerous osteoclasts-like giant cells. The diverse histomorphology and immunohistochemical characteristics of this case involving a rare tumour at a rare site is presented.

Clear cell sarcoma-like tumor of the gastrointestinal tract, presenting as a second malignancy after childhood hepatoblastoma

Clear cell sarcoma-like tumor of the gastrointestinal tract (CCSLGT) is a rare malignant neoplasm arising within the wall of the small bowel, stomach, or large bowel, predominantly in children and young adults. It is an aggressive tumor with a high rate of local recurrence, metastases, and early death from disease. Histologically, it is composed of relatively monomorphic ovoid or round cells with clear to eosinophilic cytoplasm, arranged in sheets and sometimes papillary or alveolar architectures, often with CD68-positive osteoclast-like giant cells in variable numbers, and is associated with EWSR1-CREB1 gene fusions. Its pathogenesis is unknown, and histologically it can be easily confused with a variety of intra-abdominal neoplasms. We describe a case of CCSLGT with molecular characterization, presenting as an acutely obstructing small bowel mass in a 33-year-old male, which occurred as a second malignant neoplasm 20 years after treatment with surgery, radiotherapy, and cisplatin and doxorubicin chemotherapy for childhood hepatoblastoma. This gives further insight into the clinical setting of this highly aggressive neoplasm and highlights the use of radiation therapy as a possible etiologic factor.

Clear cell sarcoma of tendons and aponeuroses of the parapharyngeal space: an unusual localization of a rare tumor (a case report and review of the literature)

The clear cell sarcoma of tendons and aponeuroses (CCSTA) is a rare soft tissue sarcoma in the head and neck region and parapharyngeal space. Over 95% of CCSTAs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of CCSTA of the head and neck region involving the parapharyngeal space in a 48-year-old men and review of the literature on CCSTA.

Selected topics in the pathology of epithelioid soft tissue tumors

Epithelioid morphology, mimicking carcinoma, is a key or defining feature of several soft tissue tumors and may be seen in a wide variety of other tumors. This review will focus on those tumors defined at least in part by their epithelioid morphology, in particular epithelioid sarcoma, epithelioid malignant peripheral nerve sheath tumor, and sclerosing epithelioid fibrosarcoma. The role of loss of the SMARCB1 tumor-suppressor gene in the pathogenesis of these epithelioid soft tissue tumors will be discussed, as will their differential diagnosis with non-mesenchymal tumors, in particular carcinoma and melanoma.

Non-antiepileptic drugs for trigeminal neuralgia

BACKGROUND

Trigeminal neuralgia was defined by the International Association for the Study of Pain as a sudden, usually unilateral, severe, brief, stabbing recurrent pain in the distribution of one or more branches of the fifth cranial nerve. Standard treatment is with anti-epileptic drugs. Non-antiepileptic drugs have been used in the management of trigeminal neuralgia since the 1970s. This is an update of a review first published in 2006 and previously updated in 2011.

OBJECTIVES

To systematically review the efficacy and tolerability of non-antiepileptic drugs for trigeminal neuralgia.

SEARCH METHODS

On 20 May 2013, for this updated review, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL (2013, Issue 4), MEDLINE (January 1966 to May 2013), EMBASE (January 1980 to May 2013), LILACS (January 1982 to May 2013) and the Chinese Biomedical Retrieval System (1978 to May 2013). We searched clinical trials registries for ongoing trials.

SELECTION CRITERIA

We included double-blind, randomised controlled trials in which the active drug was used either alone or in combination with other non-antiepileptic drugs for at least two weeks.

DATA COLLECTION AND ANALYSIS

Two authors decided which trials fitted the inclusion criteria and independently graded risk of bias. We assessed the quality of the evidence according to the GRADE criteria for this update.

MAIN RESULTS

In this 2013 update, we updated the searches, but identified only two new ongoing studies. The review includes four trials involving 139 participants. The primary outcome measure in each was pain relief. Three trials compared one of the oral non-antiepileptic drugs tizanidine, tocainide or pimozide with carbamazepine. The quality of evidence for all outcomes for which data were available was low. In a trial of tizanidine involving 12 participants (one dropped out due to unrelated disease), one of five participants treated with tizanidine and four of six treated with carbamazepine improved (risk ratio (RR) 0.30, 95% confidence interval (CI) 0.05 to 1.89). Few side effects were noted with tizanidine. For pimozide, there was evidence of greater efficacy than carbamazepine at six weeks. Up to 83% of participants reported adverse effects but these did not lead to withdrawal; the report did not provide comparable data for carbamazepine. Limited data meant that we could not assess the effects of tocainide; however, data from non-randomised studies (not included in this review) indicate that serious haematological adverse events can occur. A trial involving 47 participants compared 0.5% proparacaine hydrochloride eyedrops with placebo but did not show any significant benefits, again according to low-quality evidence. The report did not mention adverse events. The proparacaine trial was at low risk of bias; the other trials were at unclear risk of bias overall.

AUTHORS' CONCLUSIONS

There is low-quality evidence that the effect of tizanidine is not significantly different than that of carbamazepine in treating trigeminal neuralgia. Pimozide is more effective than carbamazepine, although the evidence is of low quality and the data did not allow comparison of adverse event rates. There is also low-quality evidence that 0.5% proparacaine hydrochloride eye drops have no benefit over placebo. Limitations in the data for tocainide prevent any conclusions being drawn. There is insufficient evidence from randomised controlled trials to show significant benefit from non-antiepileptic drugs in trigeminal neuralgia. More research is needed.