To assess the feasibility of apparent diffusion coefficient (ADC) generated from diffusion weighted magnetic resonance imaging as a non invasive technique to differentiate tumor recurrence from radionecrosis in patients with laryngeal carcinoma.
Materials and methods
Twenty one patients suspected of tumor recurrence underwent MRI including diffusion weighted imaging (DWI) (b 0 and 1000). ADC maps were generated and ADC values were measured at the lesion sites and the normal laryngeal tissues, and were compared with the histopathological results.
Results
The mean ADC of tumor recurrence {1.04 ± 0.34 × 10−3 mm2/s (SD)} was significantly lower (p < 0.0001) than the mean ADC of the normal laryngeal tissues in the same patient (1.48 ± 0.099 × 10−3 mm2/s) while the mean ADC of radionecrosis (1.79 ± 0.41 × 10−3 mm2/s) was significantly higher (p < 0.04) than the mean ADC of the normal laryngeal tissues (1.49 ± 0.095 × 10−3 mm2). The mean ADC of tumor recurrence is significantly lower (p < 0.0001) than the mean ADC of radionecrosis with 1.16 × 10−3 mm2/s is the best cut value for differentiating tumor recurrence from radionecrosis.
Conclusion
ADC can differentiate tumor recurrence from radionecrosis in laryngeal carcinoma.
KEYWORDS
DWI
ADC
Laryngeal carcinoma
Radionecrosis
Tumor recurrence
Cited by (0)
Available online 28 July 2011
Peer review under responsibility of Egyptian Society of Radiology and Nuclear Medicine.