Researcher evaluated the ability of different (18F) fluoro-deoxy-d-glucose (FDG)-positron emission tomography (PET)-based and magnetic resonance (MR)-based parameters to identify prevertebral space (PVS) infiltration by hypopharyngeal carcinoma.

FDG-PET/CT and FDG-PET/MR imaging have become Essential tools in the staging and post-therapeutic surveillance of advanced HNSCC.17 They provide not only information on the local tumor extent, but also allow for whole body imaging to rule out nodal disease, distant metastases,and second primaries. Before surgical treatment can be contemplated, resectability-defining factors need to be addressedby preoperative radiological assessment.10 In advancedhypopharyngeal carcinomas, fixation of the tumor to thePVS renders a surgical resection with adequate margins andfunctional outcome impossible. 

Imagingmodalities

Few studies have addressed imagingmodalities and their ability to predict a possible involvementof the PVS in advanced laryngeal or hypopharyngeal carcinomas. Righi et al. compared contrast-enhanced CT with openneck exploration in determining PVS involvement inadvanced laryngeal and hypopharyngeal carcinomas andfound an overall accuracy in predicting prevertebral muscleinvasion of 55% with concomitant low sensitivity and specificity (50% and 61%, respectively).

Researcher  evaluated the ability of different (18F) fluoro-deoxy-d-glucose (FDG)-positron emission tomography (PET)-based and magnetic resonance (MR)-based parameters to identify prevertebral space (PVS) infiltration by hypopharyngeal carcinoma. A retrospective study on 59 patients with advanced hypopharyngeal squamous cell carcinoma undergoing cross-sectional imaging and triple endoscopy for staging. Obliteration of retropharyngeal fat plane on T1-weighted MR images was found more often (P < .001) in tumors fixated to the PVS.

Complete fat plane obliteration best-predicted tumor fixation to PVS (accuracy 99%; CI: 97%-100%; P < .001). With similar accuracy, PET-based models predicted PVS fixation (combination of standardized uptake value [SUVmax ] of the primary tumor and presence of focal FDG-uptake in prevertebral muscles [accuracy 98%; CI 94%-100%; P < .001]; metabolic tumor volume [MTV] [accuracy 98%; CI 95%-100%; P < .001]).

Both the MR-based parameter of complete fat plane obliteration and PET-based models SUVmax in combination with the presence of focal FDG-uptake of prevertebral muscles; increased MTV) predict PVS involvement independently with high accuracy. Not only MR imaging but also FDG-PET imaging allows to predict PVS involvement, which represents a critical factor For therapeutic decisions in patients with advanced hypopharyngeal carcinomas. Both the MR-based parameter complete fat plane obliteration and PET-based models.

SUVmax in combination with the presence of focal FDG-uptake of prevertebral muscles; increased MTV alone) predict PVS involvement independently with high accuracy.