Fine needle aspiration of salivary gland carcinomas with high-grade transformation: A multi-institutional study of 22 cases and review of the literature.
BACKGROUND
High-grade transformation (HGT) is a rare process whereby conventional low- to intermediate-grade salivary gland carcinomas (SGC) transform into high-grade, poorly or undifferentiated malignancies with focal or complete loss of their conventional histomorphologic features. Because tumors with HGT are associated with a worse prognosis than their conventional counterparts, preoperative recognition of HGT may be of benefit for optimal patient management. Using a multi-institutional approach, we describe the largest fine needle aspiration (FNA) cohort of salivary gland carcinomas with HGT.


METHODS
The archives of 9 large academic medical centers were searched, and 22 cases of SGC with HGT were identified by surgical excision accompanied by preoperative FNA. Clinical and cytomorphologic features were retrospectively reviewed.


RESULTS
The male-to-female ratio was 14:8, and the mean patient age was 60.2 years. The average tumor size was 3.6 cm, and 19 cases were from the parotid gland. Acinic cell carcinoma with HGT was the most common tumor subtype, comprising 12 cases with HGT, followed by adenoid cystic carcinoma, secretory carcinoma, and other subtypes. Eighteen cases were classified as malignant; however, a specific diagnosis of HGT was not made. Sixteen cases contained a high-grade cytologic component, and 7 cases had a mixture of both conventional and high-grade components retrospectively.


CONCLUSIONS
SGC with HGT should be considered in the differential diagnosis of a salivary gland aspirate exhibiting high-grade cytomorphologic features. The presence of distinct tumor populations, conventional and high-grade, should prompt consideration of HGT, especially when the conventional component is acinic cell carcinoma or adenoid cystic carcinoma.
['Nakaguro|Masato|M|0000-0001-6987-3043', 'Faquin|William C|WC|0000-0002-9043-7171', 'Baloch|Zubair W|ZW|', 'Cantley|Richard L|RL|', 'Compton|Margaret L|ML|', 'Ely|Kim A|KA|', 'Holmes|Brittany J|BJ|', 'Hu|Rong|R|', 'Kerr|Darcy A|DA|0000-0002-3228-2044', 'Montone|Kathleen T|KT|', 'Nishino|Michiya|M|0000-0003-4692-4981', 'Pantanowitz|Liron|L|0000-0001-8182-5503', 'Rossi|Esther Diana|ED|0000-0003-3819-4229', 'Sadow|Peter M|PM|0000-0003-1036-6367']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D044963:Biopsy, Fine-Needle D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D060787:Neoplasm Grading D012189:Retrospective Studies D012468:Salivary Gland Neoplasms
fine needle aspiration salivary gland salivary gland carcinoma high-grade transformation acinic cell carcinoma adenoid cystic carcinoma secretory carcinoma salivary cytology