Resumen de High‑grade transformation of head and neck adenoid cystic carcinoma demonstrates distinctive clinicopathological features and an unfavorable prognosis: a matched case‑control study of the largest series in China
Ting yao Ma, Jun Wu, Shi zhi He, Xue-Lian Wang, Guo liang Yang, Shu jing Zhang, Jin Zhou, Yi ming Ding, Li feng Li, Hong fei Liu, Lan lan Xuan, Xiao hong Chen
Purpose Amidst the rarity of High-grade transformation (HGT) in adenoid cystic carcinoma (ACC), this study ofers unprecedented insights into its aggressive nature and clinical implications.
Methods A 1:1 match comparison between 23 HGT patients and non-HGT counterparts was extracted from 412 ACC cases, focusing on dissecting distinctive clinicopathological features and prognostic outcomes.
Results The predominant sites of HGT were the sinonasal and lacrimal glands (30.4% each). Notably, the solid subtype was the most prevalent pattern within HGT, accounting for 69.6% of cases. Compared to non-HGT, the HGT cohort exhibited signifcantly higher rates of lymph node metastasis (39.1% vs. 8.7%; P<0.05), perineural invasion (60.9% vs. 26.1%; P<0.05), and increased Ki-67 proliferation index (35.0% vs. 10.0%; P<0.05). Moreover, HGT regions typically showed reduced or absent p63 expression, along with high-grade pathomorphology. HGT was associated with increased recurrence (55.0%) and distant metastasis (78.3%), leading to an average survival of 35.9 months and a 3-years mortality rate of 35.0%. Overall and progression-free survival rates were signifcantly decreased in the HGT group.
Conclusion This study represents the largest single-center cohort of HGT cases to our knowledge, highlighting its frequent occurrence in the sinonasal and lacrimal glands and association with poorer outcomes. The fndings support classifying HGT in ACC as Grade 4, refecting its severity.
