Biphasic axillary synovial sarcoma diagnosed by preoperative fine‐needle aspiration cytology

Abstract

Synovial sarcoma (SS) is a soft-tissue sarcoma which usually occurs in lower extremities. Less than 20 cases of SS located in shoulder or axillary region have been reported, and these studies describe histopathological features. We report a case of axillary SS diagnosed by fine-needle aspiration cytology, immunocytochemistry, and molecular techniques performed on cytology smears. A 48-year-old woman presented with a palpable and well-defined axillary mass which measured 4 cm. On-site smears showed high cellularity with spindle cells, and a mesenchymal tumor was suspected. Definitive cytological analysis showed cells with ovoid- or comma-shaped nuclei arranged in loose sheets and fascicles, associated with naked nuclei and isolated cells. Mitotic count was 2 mitoses/HPF. Immunocytochemical studies showed vimentin and focal CK AE1-AE3 positivity. A PCR was performed and the specific translocation t(X;18) was detected. The lesion was excised and the diagnosis of biphasic SS was confirmed. The identification of SS on cytology specimens is difficult and differential diagnosis is broad. Complementary studies are necessary and they can be performed on FNA smears or cell blocks.

Cytological findings of monophasic synovial sarcoma presenting as a lung mass: report of a case and review of the literature

“…[1][2][3][4] There are a few case reports of synovial sarcoma diagnosed based on FNA biopsy. [5][6][7][8][9][10][11][12][13][14][15][16] The cases described involved widespread locations such as heart, thyroid, kidney, prostate, large vessels, parapharyngeal space, axilla, and lower extremity.…”

From fine‐needle aspiration cytology to fluorescent in‐situ hybridization in an unusual case of pharyngeal synovial sarcoma

“…FNA cytology is considered a reliable tool in the preoperative diagnosis of mesenchymal lesions, with reported positive and negative predictive values ranging from 85% to 100% to 94% to 100%, respectively …”

“…13 FNA cytology is considered a reliable tool in the preoperative diagnosis of mesenchymal lesions, with reported positive and negative predictive values ranging from 85% to 100% to 94% to 100%, respectively. 14,15 Nonetheless, the cytological diagnosis of SS is challenging, due to the bland features of the neoplastic cells. 9 A modified version of the algorithmic approach to parapharyngeal spindle cell tumors proposed by the authors is reported in Figure 3.…”

Inguinal lymph node metastasis in a case of recurrent biphasic synovial sarcoma-A cytologic diagnosis

“…Presence of myxoid stroma and heterogeneous lesions helps in distinguishing SS from myoepithelial carcinomas. [ 6 ] 'Cigar-shaped' and 'buckled' nuclei help in differentiating from leiomyosarcoma and malignant peripheral nerve sheath tumor, respectively. [ 6 ] SSs express vimentin, cytokeratin, EMA and Bcl-2 while they are negative for SMA and S-100.…”

“…[ 6 ] 'Cigar-shaped' and 'buckled' nuclei help in differentiating from leiomyosarcoma and malignant peripheral nerve sheath tumor, respectively. [ 6 ] SSs express vimentin, cytokeratin, EMA and Bcl-2 while they are negative for SMA and S-100. [ 6 ] As is shown by this case, USG can be beneficial in evaluation, aspiration and biopsies of suspicious lymph nodes.…”