Prognostic Impact of Tumor Stage and Growth Pattern in Sinonasal Adenoid Cystic Carcinoma: A 15-Year Population-Based...

Sinonasal adenoid cystic carcinoma (AdCC) has a limited prognosis. This study assesses its incidence and prognostic factors in The Netherlands, focusing on histopathological features.

Adult patients diagnosed during 2008-2022 were retrieved through the Netherlands Cancer Registry and the Dutch Pathology Registry. Prognostic factors were assessed using survival analyses.

Ninety-nine patients were included. The yearly incidence fluctuated between 3 and 14 cases (RESR: 0.02-0.08 per 100 000 person-years). Five-year overall, relative, and progression-free survival were 51%, 55%, and 62%. Multivariable analysis showed solid growth and non-surgical treatment to be independently associated with poorer overall and relative survival after correction for age, tumor location, and T stage. Non-surgical treatment was mainly used for advanced disease and was mainly palliative when intent was recorded. No significant survival differences were found among the different T stages. Sex, perineural invasion, and (lympho)vascular invasion did not impact survival.

The presence of any solid growth can be used as a prognostic indicator. The absence of survival differences between T stages may indicate that sinonasal AdCC's behavior does not fully align with the standard TNM classification, with factors such as solid growth potentially being more prognostically relevant.