Apparent diffusion coefficient values of mediastinal masses in children.

Abstract Objective Compare apparent diffusion coefficient (ADC) values between benign and malignant mass lesions in a cohort of children referred for imaging of a mediastinal mass. Material and methods Prospective study including 24 consecutive children (11 boys, 13 girls aged 5months to 16years). All underwent echo planar diffusion weighted MR imaging of the mediastinum with b -factors of 0 and 600s/mm 2 . Apparent diffusion coefficient (ADC) values were calculated and correlated with the surgical finding or biopsy. Results The mean ADC value of malignant mediastinal tumors was 0.91 (S.D., 0.17) ×10 −3 mm 2 /s and of benign lesions 1.8 (S.D., 0.33) ×10 −3 mm 2 /s. There was significant different in the ADC value between malignant tumors and benign mediastinal tumors ( P −3 mm 2 /s as a threshold value for differentiating malignant from benign mediastinal masses has an accuracy of 93%, sensitivity of 92%, specificity of 94%, positive predictive value of 94%, negative predictive value of 92% and area under the curve of 0.962. Conclusion Apparent diffusion coefficient value is a promising non-invasive parameter for assessment of mediastinal mass in children.