Is there a need for positron emission tomography imaging to stage the N0 neck in T1-T2 squamous cell carcinoma of the oral cavity or oropharynx?
OBJECTIVE
We assess whether negative findings on computed tomography (CT), magnetic resonance imaging (MRI), and/or 18F-fluorodeoxyglucose positron emission tomography (18FDG-PET) may contribute to the decision-making process of elective neck dissection (eND) in patients with squamous cell carcinoma of the oral cavity or the oropharynx (oSCC) staged cT1-T2 cN0 cM0.


METHODS
We interpreted CT, MRI, and 18FDG-PET images separately, after combining the data of CT with those of 18FDG-PET and the data of MRI with those of 18FDG-PET. Each set of results was then compared with the histopathologic results of ipsilateral or bilateral eND in a prospective, blinded study.


RESULTS
The histopathologic examination of 594 lymph nodes revealed 4 metastases less than 4 mm in diameter and 3 micrometastases (less than 2 mm) in 6 of 17 patients. On CT, MRI, and 18FDG-PET, respectively, 5, 5, and 0 cases were true-malignant (true positives) and 4, 10, and 1 cases were false-malignant (false positives). The accuracy was not enhanced by fusing CT with 18FDG-PET or MRI with 18FDG-PET.


CONCLUSIONS
The detectability threshold of occult metastases appears to be below the spatial and contrast resolution of CT, MRI, and 18FDG-PET. The decision for eND in patients with cT1-T2 cN0 cM0 oSCC cannot be based upon cross-sectional imaging at the resolutions currently available.
Schroeder
Ursula
U
Department of Otolaryngology-Head and Neck Surgery, University of Cologne Medical Center, Cologne, Germany.
Dietlein
Markus
M
Wittekindt
Claus
C
Ortmann
Monika
M
Stuetzer
Hartmut
H
Vent
Julia
J
Jungehuelsing
Markus
M
Krug
Barbara
B
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000556:secondary; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D009333:Neck; D009367:Neoplasm Staging / Q000379:methods*; D009959:Oropharyngeal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*