OBJECTIVE: MR imaging was prospectively correlated with pathologic findings to study whether MR imaging can differentiate viable from nonviable tumor tissue in the irradiated carcinoma of the tongue. SUBJECTS AND METHODS: MR examinations were performed after radiation therapy in 21 patients with carcinoma of the tongue. All patients underwent either a total glossectomy or hemiglossectomy after radiation therapy. Specimens were examined microscopically. Radiation changes were histologically graded into four groups (I, minimal cellular changes; II, presence of cellular changes and partial destruction of the tumor; III, only nonviable tumor cells; IV, no tumor cells). MR examinations included T2-weighted imaging, unenhanced T1-weighted imaging, dynamic contrast-enhanced imaging, and contrast-enhanced T1-weighted imaging. RESULTS: On unenhanced T1-weighted images, the lesion was hypointense, except for two patients with histologic grade III. On T2-weighted images, the lesion appeared hyperintense in 12 of 14 patients with viable tumor cells (grades I and II); however, the lesion was hypointense in four, and isointense in two of seven patients with nonviable tumor cells (grades III or IV). Contrast-enhanced T1-weighted images showed that the degree of contrast enhancement of the lesion was equal to or lower than that of a normal salivary gland in 18 of 21 patients. For the time of maximal enhancement of the lesion on dynamic imaging, there was no substantial difference between viable (grades I and II) and nonviable (grades III and IV) tumor tissue. CONCLUSION: The present study shows that T2-weighted imaging is feasible for differentiating viable from nonviable tumor tissue in irradiated carcinoma of the tongue.
OBJECTIVE: MR imaging was prospectively correlated with pathologic findings to study whether MR imaging can differentiate viable from nonviable tumor tissue in the irradiated carcinoma of the tongue. SUBJECTS AND METHODS: MR examinations were performed after radiation therapy in 21 patients with carcinoma of the tongue. All patients underwent either a total glossectomy or hemiglossectomy after radiation therapy. Specimens were examined microscopically. Radiation changes were histologically graded into four groups (I, minimal cellular changes; II, presence of cellular changes and partial destruction of the tumor; III, only nonviable tumor cells; IV, no tumor cells). MR examinations included T2-weighted imaging, unenhanced T1-weighted imaging, dynamic contrast-enhanced imaging, and contrast-enhanced T1-weighted imaging. RESULTS: On unenhanced T1-weighted images, the lesion was hypointense, except for two patients with histologic grade III. On T2-weighted images, the lesion appeared hyperintense in 12 of 14 patients with viable tumor cells (grades I and II); however, the lesion was hypointense in four, and isointense in two of seven patients with nonviable tumor cells (grades III or IV). Contrast-enhanced T1-weighted images showed that the degree of contrast enhancement of the lesion was equal to or lower than that of a normal salivary gland in 18 of 21 patients. For the time of maximal enhancement of the lesion on dynamic imaging, there was no substantial difference between viable (grades I and II) and nonviable (grades III and IV) tumor tissue. CONCLUSION: The present study shows that T2-weighted imaging is feasible for differentiating viable from nonviable tumor tissue in irradiated carcinoma of the tongue.
Authors: Redina Ljumanovic; Johannes A Langendijk; Otto S Hoekstra; Dirk L Knol; C René Leemans; Jonas A Castelijns Journal: Eur Radiol Date: 2008-05-20 Impact factor: 5.315