Sinonasal seromucinous hamartoma: a single institution case series combined with a narrative review of the literature.

ABSTRACT

PURPOSE: This study aimed to investigate the clinical and histopathological characteristics of sinonasal seromucinous hamartomas (SHs). METHODS: Eight patients with sinonasal SH and treated at a tertiary hospital between November 2005 and September 2023 were included. Additionally, a systematic review of published articles was conducted, analyzing 48 cases of SH described in the literature. RESULTS: Among the eight patients treated at our institution, tumors originated from the posterior nasal cavity in four patients and middle turbinate and middle meatus were the primary origin in two patients each. Coexistence of inflammatory nasal polyps (NPs) was observed in four cases. Histopathologically, four patients exhibited focal respiratory epithelial adenomatoid hamartoma (REAH) features, and low-grade dysplasia was found in one patient. A combined analysis with previous literature revealed that 46.3% of all cases originated in the anterior nasal cavity. The proportions of cases accompanied by NPs and those with focal REAH features were 20.5% and 39.1%, respectively. Additionally, the frequencies of cases exhibiting dysplastic features (5.4%) and recurrence (2.1%) were low. Remarkably, tumors originating from the anterior region tended to have a higher frequency of dysplasia than those originating from the posterior region, although this difference was not statistically significant (p = 0.0996). CONCLUSION: Patients with sinonasal SH showed favorable treatment outcomes following surgical resection. Focal REAH features and accompanying NPs were frequently observed. A substantial proportion of cases originate in the anterior nasal cavity, and these tumors may exhibit a high tendency for dysplasia.