Cytomorphologic features that distinguish schwannoma from other low-grade spindle cell lesions.

摘要: BACKGROUND Fine-needle aspiration biopsy of spindled mesenchymal lesions, including schwannomas, are challenging because overlapping cytomorphological features. The objective the current study was to identify key diagnostic cytological criteria for diagnosis schwannoma and distinguish it from its common mimics. METHODS A total 58 schwannomas were evaluated compared with 98 benign low-grade spindle cell 17 gastrointestinal stromal tumors 20 fibromatosis cases. Biopsy confirmation available all authors semiquantitatively cellularity, quality stroma (fibrous fibrillar), presence single cells bipolar cytoplasmic processes, marked nuclear pleomorphism (in absence other features malignancy). Nuclear included fishhook-type nuclei, intranuclear inclusions, chromatin pattern, nucleoli. RESULTS Schwannomas demonstrated cohesive tissue fragments fibrillary occasionally fibrous stroma. inclusions processes emerged as statistically significant differences between nonschwannoma groups. When 5 present (high numbers clusters, few no cells, stroma, nuclei pointed tips, anisonucleosis) sensitivity, specificity, positive predictive value, negative value 22%, 97%, 81%, 68%, respectively. CONCLUSIONS Cohesive fibrillary/fibrous pleomorphism, strongly suggestive assist in excluding potential mimics. Cancer (Cancer Cytopathol) 2015. © 2015 American Society. 2015;123:171–179. 2014