Basement membrane material (hyaline globules) in synovial sarcoma. A case report with description of a potential diagnostic pitfall

• Published in: Acta cytologica Vol. 42; no. 3; p. 791
• Main Authors: Dharan, M, Nachtigal, D, Rosen, G, Honigman, J, Luboshitzky, R
• Format: Journal Article
• Language: English
• Published: Switzerland 01.05.1998
• Subjects: Adult; Basement Membrane - chemistry; Basement Membrane - pathology; Biomarkers, Tumor - analysis; Biopsy, Needle; Carcinoma, Medullary - diagnosis; Collagen - analysis; Diagnosis, Differential; Female; Head and Neck Neoplasms - chemistry; Head and Neck Neoplasms - diagnosis; Head and Neck Neoplasms - pathology; Head and Neck Neoplasms - radiotherapy; Humans; Laminin - analysis; Neoplasm Proteins - analysis; Neoplasm Recurrence, Local; Sarcoma, Synovial - chemistry; Sarcoma, Synovial - diagnosis; Sarcoma, Synovial - pathology; Sarcoma, Synovial - radiotherapy; Thyroid Neoplasms - diagnosis
• ISSN: 0001-5547
• DOI: 10.1159/000331849

Synovial sarcoma (SS), a malignant mesenchymal tumor, has a biphasic growth pattern characteristically. Histologically and cytologically the tumor can pose diagnostic difficulty when the epithelial component is predominant. A 22-year-old female presented with a rapidly enlarging mass on the lower left side of the neck. Fine needle aspiration of the tumor yielded abundant, discohesive round-oval cells mingled with amorphous hyaline material, raising a suspicion of medullary carcinoma of the thyroid. In addition, air-dried, Giemsa-stained smears demonstrated rosettelike structures with central magenta globular material, mimicking adenoid cystic carcinoma. However, histologic examination of the excised tumor, including immunohistochemical and ultrastructural studies, proved it to be a typical SS with copious basement membrane accumulations. The cytologic appearance of SS can be confusing. However, a false diagnosis may be avoided if adequate needle sampling is ensured and clinical correlation considered.