Ancillary studies on cell blocks from fine needle aspiration specimens of salivary gland lesions: A multi-institutional study

• Type of Material: Article
• Authors: Seena Tabibi, Johns Hopkins University; Matthew Gabrielson, Johns Hopkins University; Carla Saoud, Johns Hopkins University; Katelynn Davis, Johns Hopkins University; Sintawat Wangsiricharoen, Johns Hopkins University; Ryan Lu, Johns Hopkins University; Isabella Tondi Resta, University of Pennsylvania; Kartik Viswanathan, Emory University; William C Faquin, Massachusetts General Hospital; Zubair Baloch, University of Pennsylvania; Zahra Maleki, Johns Hopkins University
• Language: English
• Date: 2022-01-29
• Publisher: WILEY
• Publication Version: Final Published Version
• Copyright Statement: © 2022 The Authors. Diagnostic Cytopathology published by Wiley Periodicals LLC.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1002/dc.24939
• Title of Journal or Parent Work: DIAGNOSTIC CYTOPATHOLOGY
• Volume: 50
• Issue: 5
• Start Page: 235
• End Page: 252
• Keywords: histochemistry stains; salivary gland; in situ hybridization; Milan System for Reporting Cytology; CYTOLOGY; UTILITY; Medical Laboratory Technology; immunohistochemistry; fine-needle aspiration; cell block; Science & Technology; Life Sciences & Biomedicine; ancillary studies; Pathology
• Research Categories: Health Sciences, Medicine and Surgery; Health Sciences, Pathology

Abstract

Background: Ancillary studies are commonly performed on cell blocks prepared from fine-needle aspiration (FNA) specimens. There are limited studies in application of ancillary studies on cell blocks from salivary gland (SG) FNAs. This multi-institutional study evaluates the role of ancillary studies performed on cell blocks in the diagnosis of SG lesions, and their impact on clinical management. Method: The electronic pathology archives of three large academic institutions were searched for SG FNAs with ancillary studies performed on cell blocks. The patient demographics, FNA site, cytologic diagnosis, ancillary studies, and surgical follow-up were recorded. If needed, the cytologic diagnoses were reclassified as per the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC). Results: 117 SG FNA cases were identified including 3, 10, 11, 6, 23, 4, and 60 cases in MSRSGC categories I, II, III, IVa, IVb, V, VI, respectively with surgical follow-up available ranging from 27% to 100% within each category. Ancillary studies including histochemistry, immunocytochemistry (IHC), and in situ hybridization (ISH) were beneficial in 60%–100% of cases in each category. Risk of malignancy was 100% in both the suspicious for malignancy (V) and malignant (VI) categories. Ancillary studies improved diagnosis in 60% of non-neoplastic cases (II, 6/10), 100% of benign neoplasm cases (IVa, 6/6), and 98.3% of malignant cases (VI, 59/60). Conclusion: Judicious and case-based ancillary studies performed on SG FNA cell blocks with sufficient material can improve the diagnostic yield by further characterization of the atypical/neoplastic cells, particularly in MSRSGC categories IVa-VI.