Is preoperative cytologic diagnosis of epithelioid sarcoma possible?

Soft Tissue Fine-Needle Aspiration: Current and Future Impact on Patient Care

Soft tissue neoplasms pose many diagnostic challenges on fine-needle aspiration (FNA), owing largely to their rarity, large number of entities, and histologic diversity. Advances in ancillary testing now allow detection of the characteristic immunophenotypes and molecular alterations for many neoplasms and include reliable surrogate immunohistochemical markers for underlying molecular events that are highly efficient in small biopsies. A morphology-based framework is recommended to guide appropriate differentials and judicious selection of ancillary tests for small biopsies. The accurate diagnosis of soft tissue tumors is crucial for patient management and prognostication, with many potential implications in this era of precision medicine.

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.

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.

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.

Proximal-type epithelioid sarcoma of the maxilla with metastasis to the scalp: Cytologic findings of an unusual malignant tumor

Epithelioid sarcoma of proximal type (ESPT), a subtype of epithelioid sarcoma, is an uncommon malignant neoplasm of the soft tissue with histo- and cytologic features similar to epithelioid sarcoma, classic type and to the more commonly encountered extra-renal malignant rhabdoid tumor (EMRT). Unlike classic epithelioid sarcoma, ESPT usually involves pelvic, perineal, and genital regions and has an aggressive clinical course. Like EMRT, ESPT can have aberrations of the INI1 gene on chromosome 22q, which results in the loss of INI1 protein expression. We describe here the cytological findings of an ESPT metastatic to the scalp in a 14-year-old boy. Cytological preparations showed a discohesive population of pleomorphic ovoid to polygonal cells with large irregular nuclei and prominent nucleoli. Isolated cells with rhabdoid features were noted. These cells had abundant cytoplasm and occasional intracytoplasmic hyaline inclusions. In the light of the patient's clinical history of a known primary ESPT of the maxilla, the cytologic features were distinct enough to render a diagnosis of a metastatic lesion to the skull.