Fine-needle aspiration of epithelioid sarcoma: cytology findings in nine cases

Fine needle aspiration biopsy of epithelioid-mesenchymal neoplasm with PTCH1-GLI1 fusion: A case report

Mesenchymal tumors harboring GLI1 gene fusions are a rare new entity that typically occur in the head and neck region of young to middle aged adults, with a particular predilection for the tongue. We report herein a case of epithelioid mesenchymal tumor with PTCH1-GLI1 gene fusion of the right submental region in an 82-year-old male never smoker. Ultrasound-guided fine needle aspiration (FNA) with concomitant core needle biopsy was performed. Cytology smears revealed a hypercellular, monotonous aspirate comprised of epithelioid to plasmacytoid cells with round regular nuclei and moderate amounts of cytoplasm. There were admixed granulomata. The patient underwent surgical resection with limited neck dissection and subsequent pathologic examination with performed next generation sequencing confirmed the presence of epithelioid mesenchymal tumor with PTCH1-GLI1 gene fusion. To our knowledge, this is the first reported example of a mesenchymal tumor harboring GLI1 gene fusion initially evaluated by FNA.

Cytomorphologic Spectrum of SMARCB1-Deficient Soft Tissue Neoplasms

OBJECTIVES

The SWI/SNF complex core subunit SMARCB1 is inactivated in a variety of neoplasms that share characteristic "rhabdoid" cytomorphology. The aim of this study was to evaluate SMARCB1-deficient soft tissue neoplasms on cytology to identify diagnostic clues.

METHODS

Eleven SMARCB1-deficient tumors, including six epithelioid sarcomas, three malignant rhabdoid tumors, one epithelioid malignant peripheral nerve sheath tumor (MPNST), and one poorly differentiated chordoma with fine-needle aspiration (FNA), serous effusion, or touch prep (TP) from two institutions, were included. Targeted next-generation sequencing (NGS) was performed in two cases.

RESULTS

Evaluation of FNA (n = 4), effusion (n = 4), and TP (n = 3) in nine adult and two pediatric patients demonstrated cellular samples (n = 11), epithelioid cells with rhabdoid morphology (n = 9), eccentrically located nuclei with prominent nucleoli (n = 7), and cytoplasmic bodies (n = 4); two patients were diagnosed on FNA with cell block. Immunohistochemistry (IHC) demonstrated SMARCB1 loss in all cases and keratin and/or EMA expression in all but the epithelioid MPNST; NGS identified SMARCB1 inactivation in both cases.

CONCLUSIONS

SMARCB1-deficient soft tissue neoplasms comprise a variety of tumors with epithelioid morphology and frequent expression of keratin and/or EMA. Recognition of characteristic rhabdoid morphology on cytology can prompt IHC and/or NGS testing for SMARCB1 deficiency and help establish the diagnosis.

Epithelioid sarcoma of the hand: a wolf in sheep's clothing

Epithelioid sarcoma (ES) of the hand is a rare, aggressive cutaneous malignancy with high rates of recurrence, metastases and mortality. With an incidence rate of 0.4 cases/y per one million population, which compromise for approximately 1-1.4% of all soft tissue sarcoma, ES accounts for 10% of soft tissues sarcomas of the hand and foot. Its aggressiveness and propensity to spread and metastases without being noticed, makes it unique and potentially lethal. Missed or delayed diagnosis are often encountered as this tumor can mimic variety of different entities and due to the infrequent nature of this lesion, treatment options are still controversial. The authors provide systemic review of the current literature on epidemiology, etiology, pathogenesis, management and outcomes of this disease as well as a case presentation and a proposed treatment algorithm. The choice of treatment option depends on disease characteristics, staging at presentation, regional lymph node involvement, comorbidities and performance status of the patient. Emphasis on a multidisciplinary coordinated care is crucial as early diagnosis and treatment can decrease morbidity and mortality rates.

Cytopathology of classic type epithelioid sarcoma: a series of 20 cases and review of the literature

INTRODUCTION

As a rare soft tissue malignancy, epithelioid sarcoma (EpS) is infrequently subjected to cytopathologic analysis. With the exception of a few series, the cytology literature regarding EpS is largely limited to single case reports. Our purpose was to evaluate our experience with EpS, and review the literature regarding its cytopathology.

MATERIALS AND METHODS

A search was made of our cytopathology and surgical pathology databases for cases diagnosed as EpS. Fine-needle aspiration biopsy smears and imprint smears were performed and examined using standard technique. Effusion samples were processed using liquid-based slides.

RESULTS

Twenty cases of EpS were retrieved from 10 patients (M:F 1:1; mean age = 36 years). One patient had 5, 1 patient had 3, and 3 patients had 2 separate specimens. All patients had prior or subsequent tissue confirmation of EpS; all were of the classic/distal type. Seven were new patient cases, 7 were locally recurrent, and 6 were metastases. Sites included lower extremity (8 cases), upper extremity (4), trunk (4), serous effusion (2), scalp (1), and mediastinum (1). Specific cytologic diagnosis were EpS (13 cases), sarcoma not otherwise specified (5), and malignant neoplasm (2). All cases where cell-block SMARCB-1 staining was used were specifically recognized as EpS. Cytomorphology was composed primarily of epithelioid/plasmacytoid cells having eccentrically positioned nuclei, moderate cytoplasm, and variable nuclear pleomorphism.

CONCLUSION

The cytopathology of EpS is somewhat variable, morphologically non-specific, and mimics that of other neoplasms with epithelioid features. Ancillary immunostaining is necessary for a specific diagnosis in newly encountered patients.

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.

FNA of epithelioid sarcoma: Curie Institute experience and critical review of the literature

BACKGROUND

Epithelioid sarcoma (ES) is a rare mesenchymal tumor that is divided into 2 types: classic and proximal. To the authors' knowledge, ES has been poorly studied in cytology, with fewer than 50 cases reported to date. The objective of the current study was to analyze the cytological and immunohistochemical information regarding 5 cases of ES.

METHODS

Five cases of ES were analyzed: 4 of proximal type and 1 of classic type. The cases were taken from 4 female patients and 1 male patient. The patients ranged in age from 10 to 75 years.

RESULTS

All smears obtained from the proximal type of ES were found to be hypercellular with a necrotic and inflammatory background. Smears from classic-type ES were hypocellular with a hemorrhagic background. Large, dispersed epithelioid cells and loosely cohesive groups of cells were most frequently noted in all cases. All cases of proximal-type ES demonstrated rhabdoid cells and marked nuclear atypia, but in only one case were rhabdoid cells found to be dominant. ES diagnoses were confirmed by immunohistochemistry in histological material. In 4 cases, epithelial marker expression was noted, whereas CD34 was found to be positive in only the classic type of ES. In 2 cases, total loss of SMARCB1/INI1 nuclear expression was observed. In the 2 SMARCB1/INI1-positive cases, loss of SMARCA2/BRM expression was observed in one case and partial loss was observed in the other case.

CONCLUSIONS

The proximal type of ES differs from the classic type by the presence of rhabdoid cells and marked nuclear atypia. A specific immunohistochemical profile demonstrating loss of SMARCB1/INI1 or other proteins from the SWI/SNF complex also may be indicative of this diagnosis.

Applications of Ancillary Testing in the Cytologic Diagnosis of Soft Tissue Neoplasms

Soft tissue neoplasms are diagnostically challenging, although many advances in ancillary testing now enable accurate classification of fine-needle aspiration biopsies by detection of characteristic immunophenotypes (including protein correlates of molecular alterations) and molecular features. Although there are many useful diagnostic immunohistochemical markers and molecular assays, their diagnostic utility relies on correlation with clinical and morphologic features, judicious application, and appropriate interpretation because no single test is perfectly sensitive or specific. This review discusses applications of ancillary testing for commonly encountered soft tissue neoplasms in cytopathologic practice in the context of a pattern-based approach.

Soft Tissue Tumor Immunohistochemistry Update: Illustrative Examples of Diagnostic Pearls to Avoid Pitfalls

CONTEXT

- Current 2013 World Health Organization classification of tumors of soft tissue arranges these tumors into 12 groups according to their histogenesis. Tumor behavior is classified as benign, intermediate (locally aggressive), intermediate (rarely metastasizing), and malignant. In our practice, a general approach to reaching a definitive diagnosis of soft tissue tumors is to first evaluate clinicoradiologic, histomorphologic, and cytomorphologic features of the tumor to generate some pertinent differential diagnoses. These include the potential line of histogenesis and whether the tumor is benign or malignant, and low or high grade. Although molecular/genetic testing is increasingly finding its applications in characterizing soft tissue tumors, currently immunohistochemistry still not only plays an indispensable role in defining tumor histogenesis, but also serves as a surrogate for underlining molecular/genetic alterations. Objective- To provide an overview focusing on the current concepts in the classification and diagnosis of soft tissue tumors, incorporating immunohistochemistry. This article uses examples to discuss how to use the traditional and new immunohistochemical markers for the diagnosis of soft tissue tumors. Practical diagnostic pearls, summary tables, and figures are used to show how to avoid diagnostic pitfalls.

DATA SOURCES

- Data were obtained from pertinent peer-reviewed English-language literature and the authors' first-hand experience as bone and soft tissue pathologists.

CONCLUSIONS

- -The ultimate goal for a pathologist is to render a specific diagnosis that provides diagnostic, prognostic, and therapeutic information to guide patient care. Immunohistochemistry is integral to the diagnosis and management of soft tissue tumors.

Fine Needle Aspiration Cytology for Soft Tissue Tumours of the Hand

The purpose of this study was to evaluate the usefulness of fine needle aspiration cytology for the preoperative diagnosis of soft tissue tumours of the hand. Fine needle aspiration cytology was performed on 93 soft tissue tumours of the hand which were classified as malignant, benign or unclassified based on cytological findings. We also attempted to make specific diagnosis by cytology. The cytological diagnosis was then compared with the postoperative histopathological diagnosis. The cytological differentiation between benign and malignant tumours showed neither false-positive nor false-negative results. Of the 47 lesions with sufficient material for cytology and that were postoperatively diagnosed histologically, 35 (including one recurrent lesion) were correctly diagnosed by fine needle aspiration cytology. No complications were encountered. Fine needle aspiration cytology has a high degree of diagnostic accuracy and safety for soft tissue tumours of the hand.

Fine-needle aspiration cytology of recurrent epithelioid sarcoma of the foot: Role of immonocytochemistry in definitive diagnosis

Fine-needle aspirations (FNA) have played a crucial role in the diagnosis and follow-up of malignancies including sarcomas. However, relatively low specificity in the classification of sarcoma is the main limitation of FNA. Epithelioid sarcoma is a rare tumor of soft tissues. Very few individual case reports describing cytological features of epithelioid sarcoma have been documented in the literature. Here, we describe cytological features of epithelioid sarcoma with immunocytohistological correlation.

Fine needle aspiration cytology of epithelioid sarcoma

In this case report, we have described the fine needle aspiration cytology (FNAC) of epithelioid sarcoma (ES) in a 40-year-old female patient who presented with multiple nodular swellings over right forearm and single right axillary lymph node. The FNAC smear showed predominantly dispersed as well as three-dimensional clusters of malignant cells admixed with basement membrane like material. The individual cells were moderately pleomorphic with round to oval nuclei and moderate to abundant amount of cytoplasm. The neoplastic cells have well-defined cytoplasmic borders and intercellular spaces. The excision biopsy of the swelling of the forearm showed ES. The cytology features of ES are characteristic and a preoperative diagnosis is helpful for proper management of the case.

Fine needle aspiration biopsy of epithelioid hemangioendothelioma of the oral cavity: Report of one case and review of literature

Epithelioid hemangioendothelioma (EHE) is an uncommon vascular tumor with biological behavior intermediate between hemangioma and angiosarcoma. It rarely occurs in the oral cavity. We report a case of an 81-yr-old woman with a 2-mo history of a 2 x 2 cm2 submucosal buccal mass. Fine needle aspiration (FNA) smears were paucicellular and showed mainly single atypical large epithelioid cells in a bloody background. The atypical cells had abundant dense cytoplasm, some with fine vacuoles. Occasionally, cells with large cytoplasmic lumina were seen. Cytology preparations from fresh tissue received for frozen section revealed numerous neoplastic cells with large intracytoplasmic lumina, some of which contained red blood cells. In addition, cells with distinct intranuclear inclusions were present. Histologic sections and immunohistochemical stains confirmed the diagnosis of EHE. Although the histologic features of EHE are well recognized, reports of FNA cytology findings are sparsely existent in the literature as several case reports. The characteristic cytological features of EHE are reviewed in this report. We believe that the diagnosis of this rare tumor can be suggested when an adequate FNA specimen is obtained.

Cytological features of epithelioid mesenchymal neoplasms: A study of 21 cases

Epithelioid mesenchymal neoplasms (EMNs) are rare tumors that share cytological, histological, and immunohistochemical features with epithelial tumors. It is important to distinguish EMNs from epithelial tumors in cytology specimens due to their different clinical management and prognosis. The cytomorphological features of histologically confirmed EMN were reviewed. Twenty-one cytological specimens of EMN were evaluated and characterized by polygonal cells with moderate to abundant dense cytoplasm, prominent nucleoli, and pleomorphism. Additional findings included the presence of a distinct population of spindle cells, hemosiderin-containing cells, multinucleated cells, and granuloma-like structures in selected cases. Cytokeratin immunoreactivity was seen in two cases and was negative in one case. This study shows that the cytological features of EMNs and epithelial tumors overlap; nonetheless, some features are more helpful in suggesting EMN. A panel of immunocytochemical studies must include specific mesenchymal markers to avoid a misdiagnosis of carcinoma in cases of cytokeratin-positive EMN.

Cytologic findings of malignant vascular neoplasms: a study of twenty-four cases

Cytologic characterization of malignant vascular neoplasms (MVN) is difficult due to the wide range of differential diagnoses and sampling errors. The objective of this study was to identify criteria helpful in the cytologic diagnosis of MVN. The clinical presentation and cytomorphologic features of 22 angiosarcomas and two hemangioendotheliomas were analyzed. The criteria evaluated included cellularity, cellular arrangement, cell shape and size, pleomorphism, cytoplasmic borders, nuclear shape and number, chromatin pattern, nucleoli, background, and presence of angioformative structures. A previous history of MVN was noted in 18 of 24 patients. Specimens with epithelioid morphology were more cellular and pleomorphic and contained multinucleated cells. Specimens with spindle morphology were usually less cellular and less pleomorphic. Angioformative structures were identified in 11 of 24 cases. Awareness of features suggestive of MVN is necessary to raise the possibility of vascular origin, which can be confirmed with appropriate immunocytochemical studies.