Difficulty in Cytological Diagnosis of Clear Cell Sarcoma - A Clinicopathological Correlation.

The rarity of Clear Cell Sarcoma (CCS) and its overlapping morphology with other soft tissue tumours brings diagnosis under suspicion. Several series have described histopathologic features however, only few series have described cytological features. This series represents cytohistopathological correlation with emphasis on diagnostic difficulties and the role of ancillary studies. This series concerns six patients who presented at our hospital between 2002-2012. FNAC smears showed epithelioid to spindle cells, scattered or in focal clusters or pseudoacinar pattern. Most cells (n=5) had round to oval eccentrically placed nuclei. Multinucleated tumour giant cells and binucleated cells were (n=2) present. The cell clusters (n=2) demonstrated three dimensional clustering and pseudoacinar structures. Necrosis (n=1) was noted. The histopathological pattern showed variable sized nests of uniform plump to spindle cells with clear to pale cytoplasm separated by fine to coarse fibrous septae. Cells were epithelioid (n=2), with nuclear pleomorphism (n=2), prominent nucleoli (n=3), cytoplasmic vacuoles (n=1) and multinucleated giant cells (n=1). The mitotic rate varied from 3 to 11/HPF. Tumour necrosis and bone involvement were seen (n=2). A microcystic growth pattern (n=1) was seen in the locally recurrent tumour. Melanin and Masson-Fontana were negative. All cases were positive for HMB-45 antibodies. Accurate pathologic recognition could aid in the institution of prompt surgery and could delay or avoid recurrences. [ABSTRACT FROM AUTHOR]