Aims and objectives
Since its introduction in clinical practice,
MRI played a fundamental role in the diagnosis of Head and Neck cancer.
DWI is an MR technique that studies molecular diffusion,
inparticularthe Brownian motion of water protons in biologic tissue.
Neoplastic structures are more densely cellulated and have a larger number of cellular membranes; due to that,
theypresent a greater impediment to molecular diffusion and lower Apparent Diffusion Coefficient (ADC) values than normal structures; therefore,
DWI improves the detection of cancer especially in head and neck[1].
Oropharynxcanrepresent a...
Methods and materials
We retrospectively evaluated 17 patients that underwent neck MRI at our institution.
Nine patients had biopsy-proven T2-T4 Oropharyngeal SCC that affected a tonsil or the base of the tongue.
Eight patients with LH that underwent MRI for other indications were enrolled as negative controls.
MR imaging was performed on 1.5T MR scanner with the manufacturer’s phased-array head and neck coil.
DWI was performed using a spin-echo echo-planar imaging (EPI) sequence with the following parameters: Field of View (FOV) of 230x230 mm,
section thickness of 4...
Results
The accuracy of our model in discriminating SCC from Lymphatic Hyperplasia was 94,1% with an AUC of 0,89 (Fig.
3).
The confusion matrix (Fig.
4) showed that none of the LH were recognized as SCC,
while 2 of the SCC were recognized as LH.
Conclusion
In western countries 90% of Oropharyngeal Cancers are SCC,usuallyHPV positive [4]: these malignancies tend tocause early lymphatic involvement when compared with HPV negative malignancies.
Sometimes lymphatic metastases are the only sign of malignancy, a well-recognized clinical scenario of “unknown primary tumour” that can account up to 7% of head and neck cancers [5].
Most of these tumors presumably originate from the Oropharynx[6].
Palatine tonsil and tongue base are therefore critical spots for the radiologist in detecting SCC in MRI: morphological changes,
as unilateral tonsillar enlargement,...
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