MR imaging of squamous cell carcinoma of the floor of the mouth. Appearance of the sublingual and submandibular glands.
OBJECTIVE
To determine the diagnostic value of MR imaging for tumors of the floor of the mouth and the effects of the tumors on the sublingual and submandibular glands.


METHODS
Thirty-seven patients with proven squamous cell carcinoma of the floor of the mouth underwent MR imaging, including unenhanced T1-weighted, T2-weighted, dynamic, and contrast-enhanced T1-weighted images. The appearance of the tumor and the sublingual and submandibular glands was assessed qualitatively and quantitatively.


RESULTS
All tumors demonstrated replacement of the normal signal intensity in the adjacent sublingual gland. Twenty-one patients (57%) had abnormal signal intensity of the submandibular gland without tumor invasion, presumably secondary to submandibular duct obstruction by the tumor. Unenhanced T1-weighted images provided high contrast between tumor and sublingual gland. Tumors limited within the gland were well detected on unenhanced T1-weighted images. Large tumors extending beyond the gland were well delineated on dynamic images, but no better than on T2-weighted images.


CONCLUSIONS
At MR imaging for tumor of the floor of the mouth, one must carefully evaluate the appearance of the sublingual and submandibular glands. Contrast-enhanced studies are unnecessary when the tumor is limited within the sublingual gland on precontrast MR images.
Murakami
R
R
Department of Radiology, Kumamoto University School of Medicine, Japan.
Baba
Y
Y
Nishimura
R
R
Baba
T
T
Nakaura
T
T
Ishikawa
T
T
Takahashi
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009060:Mouth Floor; D009062:Mouth Neoplasms / Q000175:diagnosis*; D013361:Sublingual Gland / Q000473:pathology*; D013363:Submandibular Gland / Q000473:pathology*
D003287:Contrast Media; D019786:Gadolinium DTPA