Aims: No published series describes adenoid cystic carcinoma (ACC) in the Omani population. We characterised its demographic profile, clinicopathological features and patterns of failure at a national referral centre and benchmarked these against population-based data.
Methods: Retrospective cohort of 12 consecutive patients with histologically confirmed ACC of any primary site, diagnosed March 2015 to February 2025, with follow-up censored 27 June 2026. Proportions are reported with exact 95% binomial confidence intervals (CI); no inferential comparisons were made given the sample size.
Results: Median age at diagnosis was 39.5 years (range 14-56); 6/12 were diagnosed before age 40, including two adolescents (14 and 17 years) [1]. Ten of 12 were female (83%; 95% CI 52-98%), against 59.9% female and a mean age of 57.4 years in United States Surveillance, Epidemiology, and End Results (SEER) analyses [2,3]; a regional Emirati series was male-predominant [4]. Primary sites were major salivary glands in 7 (parotid 6, submandibular 1), minor salivary glands in 3 and non-salivary sites in 2. Ten presented with a painless mass; 10 had localised disease; 3 had clinical cranial-nerve involvement. Eleven underwent surgery and all 12 received radiotherapy; 7 of 9 resections with an evaluable margin were R1. Over a median follow-up of 47.5 months (range 14-119), 9/12 developed distant metastases (75%; 95% CI 43-95%), involving lung in 6 of 9, and 6/12 developed local recurrence. At censoring, 9 were alive with disease, 2 had no evidence of disease and 1 had died of ACC.
Conclusions: ACC in this first Omani series presented substantially younger and with stronger female predominance than population-based benchmarks, with high rates of margin positivity and distant metastasis but preserved medium-term survival. Findings are hypothesis-generating, given the small single-centre sample and possible referral bias, and support multi-institutional Gulf collaboration with prolonged follow-up.