Background:
Fluorodeoxyglucose (FDG) positron emission tomography (PET) is a commonly used investigation to diagnose and stage malignancy. A systematic review and meta-analysis was conducted to assess the prevalence of incidental FDG avidity in the oropharynx and malignancy risk.
Methods:
A comprehensive literature search of PubMed, Embase and Cochrane for studies on incidental FDG avidity in the oropharynx was conducted. Studies including patients undergoing PET-CT for head and neck cancer were excluded. Meta-analysis was performed using random effects model.
Results:
The initial search yielded 1362 results and ultimately five studies were included for analysis. To assess prevalence three studies were analysed and included data comprised of 25,173 FDG PET/CT scans of which 693 contained incidental avidity in the oropharynx. A high degree of heterogeneity was observed for prevalence data (I2 of 99.82%), as well as for data on malignancy risk (I2 of 95.8%). The pooled prevalence of incidental uptake in the oropharynx was 5% (range 1-10%) and the pooled prevalence of malignancy in incidental FDG avidity was 6% (range 1-23%).
Conclusions:
Incidental uptake in the oropharynx on PET scan is common. There is a lack of high-quality data to inform the management of these patients.