Sinonasal small cell neuroendocrine carcinoma (SNEC) is an extremely rare and aggressive neoplasm that can arise in the sinonasal region. These tumors are associated with high morbidity and mortality, are difficult to diagnose, and are hard to treat. We describe 2 cases of this poorly understood malignancy and review imaging, pathology, and treatment decisions. A 41-year-old male and a 64-year-old female presented to a tertiary center in 2019 after developing nasal obstruction and were found to have sinonasal masses on imaging. Both biopsies showed strong expression of pancytokeratin with dot-like reactivity and expression of neuroendocrine markers chromogranin and synaptophysin. The findings were diagnostic of SNEC. Staging positron emission tomography/computed tomography and brain MRI were performed, and patients were discussed at a multidisciplinary tumor board. Neither had distant metastatic disease at presentation. One patient had no intracranial or orbital disease and underwent a subtotal endoscopic resection with adjuvant chemoradiation. The other patient demonstrated middle cranial fossa, dural, and orbital involvement as well as cranial nerve V palsy. This patient was treated with induction chemotherapy, followed by concurrent chemoradiation. Both patients are presently alive at 4 months follow-up, but one with persistent local disease and the other distant metastasis. Sinonasal small cell neuroendocrine carcinoma is a rare and poorly understood malignancy with an aggressive clinical course. Continued careful review of pathology and study of molecular features are needed for improved understanding of SNEC, and particularly for head and neck SNEC, to establish a staging system and better formulate treatment protocols.

The current study aims to provide stronger evidence to aid in our understanding of the role of cumulative occupational exposure to (softwood-dominated) mixed wood dust in aetiology of nasal cancer. We included broad exposure occurred in a range of wood-processing occupation across varied industries in four Nordic countries. A population-based case-control study was conducted on all male cases with nasal adenocarcinoma (393 cases), other types of nasal cancer (2,446) and nasopharyngeal cancer (1,747) diagnosed in Finland, Sweden, Norway and Iceland between 1961 and 2005. For each case, five male controls, who were alive at the time of diagnosis of the case (index date), were randomly selected, matched by birth-year and country. Cumulative exposures (CE)s to wood dust and formaldehyde before the index date were quantified based on a job-exposure matrix linked to occupational titles derived from population censuses. Hazard ratios (HRs) for the CE of wood dust were estimated by conditional logistic regression, adjusted for CE to formaldehyde and 95% confidence intervals (CIs) were calculated. There was an increasing risk of nasal adenocarcinoma related to wood dust exposure. The HR in the highest CE category of wood dust (≥ 28.82 mg/m3 -years) was 16.5 (95% CI 5.05-54.1). Neither nonadenocarcinoma of the nose nor nasopharyngeal cancer could be linked to wood dust exposure. CE to softwood-dominated mixed wood dusts is strongly linked with elevated risk in nasal adenocarcinoma but not with other types of nasal or nasopharyngeal cancer.