Adenoid Cystic Carcinoma (AdCC): A Clinical Survey of a Large Patient Cohort

SIMPLE SUMMARY: Adenoid cystic carcinoma (AdCC) is a rare heterogenous disease, often difficult to diagnose and prognosticate and, therefore, also challenging to treat optimally. To gain more knowledge with regard to clinical parameters, we conducted a retrospective study on a large cohort of AdCC of the head and neck. The strongest favourable prognostic factors were disclosed to be early disease stage (stage I and II) vs. late disease (stage III and IV) and major salivary gland subsite as compared to other subsites, with the best prognosis in the parotid gland, irrespective of the stage of the disease. Contrary to some studies, we did not find a significant correlation between survival regarding the perineural invasion and radical surgery. However, similar to others, we confirmed that other common prognostic factors, such as smoking, age, and gender, did not correlate to survival and should not be used for prognostication of AdCC of the head and neck. ABSTRACT: Adenoid cystic carcinoma (AdCC), a rare heterogenous disease, presents diagnostic, prognostic, and therapeutic challenges. To obtain more knowledge, we conducted a retrospective study on a cohort of 155 patients diagnosed in 2000–2022 with AdCC of the head and neck in Stockholm and investigated several clinical parameters in correlation to treatment and prognosis in the 142/155 patients treated with curative intent. The strongest favourable prognostic factors were early disease stage (stage I and II) as compared to late disease (stage III and IV) and major salivary gland subsite as compared to other subsites, with the best prognosis in the parotid gland, irrespective of the stage of the disease. Notably, in contrast to some studies, a significant correlation to survival was not found for perineural invasion or radical surgery. However, similar to others, we confirmed that other common prognostic factors, e.g., smoking, age, and gender, did not correlate to survival and should not be used for prognostication of AdCC of the head and neck. To conclude, in AdCC early disease stage, major salivary gland subsite and multimodal treatment were the strongest favourable prognostic factors, while this was not the case for age, gender and smoking nor perineural invasion and radical surgery.