Epithelioid sarcoma in FNAB smears

Abstract

FNAB smears of eleven epithelioid sarcomas were reviewed and analysed. Ten cases had a very similar cytomorphologic picture composed predominantly of dissociated epithelioid-like cells with eccentrically placed nuclei. These tumors were clearly malignant but difficult to differentiate morphologically from melanoma, epithelioid leiomiosarcoma, and Schwannoma or adenocarcinoma. One case was composed of spindle cells and was reminiscent of a fibrohistiocytic tumor. Immunocytochemical reactions to vimentin and cytokeratin were performed in six cases on the Papanicolaou stained smears. The reactions to both antigens were positive in all six cases. Ultrastructural characteristics of eight of the tumors are also described. It seems that epithelioid sarcoma has a rather distinct cytomorphologic picture. Taking into consideration clinical data and using also immunocytochemistry, a definitive diagnosis of epithelioid sarcoma can probably be given from FNAB smears.

Fine Needle Aspiration Cytology of Primary Epithelioid Sarcoma

“…14 Pohar-Marinsek et al identified a pale, juxtanuclear region in the tumor cells of this type of sarcoma that corresponded to the presence of intermediate filaments. 3 Electron microscopically, rich intermediate filaments, ribosomes and rough endoplasmic reticula have been observed in the abundant cytoplasm …”

“…3,15 In addition, features of an epithelial nature, such as surface extensions (microvilli or filopodia) and desmosomelike intercellular junctions, have been observed under an electron microscope. 3,15 The differential diagnoses of epithelioid sarcoma using FNA cytology include granulomatous processes, squamous cell carcinoma, adenocarcinoma, undifferentiated carcinoma, amelanotic melanoma, clear cell sarcoma, rhabdomyosarcoma, malignant rhabdoid tumor, epithelioid hemangioendothelioma, epithelioid leiomyosarcoma, epithelioid malignant peripheral nerve sheath tumors, sclerosing epithelioid fibrosarcoma, alveolar soft part sarcoma and synovial sarcoma. [3][4][5][6]10,13 To differentiate these lesions from epithelioid sarcoma cytologically, consideration of the clinical information and radiologic findings is important, and immunohistochemical studies should be performed when necessary.…”

“…2 There have been a small number of reports on the fine needle aspiration (FNA) cytology of this tumor, particularly of primary lesions, but the cytologic features have not been fully elucidated to date. [3][4][5][6] We present the cytologic findings following FNA in 2 cases of primary epithelioid sarcoma; 1 of them was difficult to differentiate from extraskeletal osteosarcoma by FNA cytology due to the presence of osteoidlike matrix on smears.…”

Cytoarchitectural Findings in the Diagnosis of Primary Soft Tissue Tumors

“…43 Aspirates from epithelioid hemangioendothelioma not containing intracytoplasmic vacuoles may totally overlap with those of epithelioid sarcoma ( Figure 26). 59,112,127 This sarcoma, seen in children, teenagers and young adults, is often confused histologically with a benign lesion due to its scarce cellular atypia. It habitually occurs in distal parts of the upper limbs (wrist, hand), 43 although rare proximal forms have also been reported recently.…”

“…It habitually occurs in distal parts of the upper limbs (wrist, hand), 43 although rare proximal forms have also been reported recently. 103 Diagnosis requires close clinical correlation and immunocytochemical analysis since cells express cytokeratin and vimentin 43,127 but are not reactive for CD31, CD34, FVIII, S-100, CEA or HMB-45. 43 The possibility of this sarcoma should be borne in mind when examining aspirate from the distal parts of extremities in children or young adults.…”