Sinonasal Intestinal-Type Adenocarcinoma in the Netherlands: A Nationwide Study (2008-2022)

BACKGROUND: Intestinal-type adenocarcinoma (ITAC) is a rare sinonasal malignancy with poor survival. By creating a clinical and epidemiological overview of the Dutch ITAC population between 2008 and 2022, this study aims to identify areas for improvement in ITAC management.

METHODS: A systematic query within the Netherlands Cancer Registry (NCR) was performed to assemble the nationwide ITAC cohort. Incidence calculations were performed alongside overall survival (OS) and relative survival (RS) estimations.

RESULTS: 171 patients were included. Yearly incidence was low (0.04-0.12 per 100 000 person-years) and showed a non-significant, slight upward tendency. The population was predominantly male (92.5%), diagnosed at advanced stages (55% ≥ cT3) and sparsely presented with regional (4.7%) and/or distant metastases (5.9%). The 5-year OS (47.8%, 95% CI: 39.4%-55.6%) and RS (55.5%, 95% CI: 45.8%-64.6%) rates were poor. The addition of radiotherapy to surgery yielded better OS and RS compared to surgery alone.

CONCLUSION: ITAC incidence shows a minimal upward tendency in the Netherlands, and survival chances remain poor. Ongoing vigilance in high-risk industries and the further implementation of adjuvant radiotherapy may lead to improved outcomes in the future. Biology-driven research is warranted to additionally tailor treatment strategies.