Fig. 2

Osteosarcoma of the proximal right tibia in a 16-year-old boy. a Axial ADC map shows low signal intensity of the tumor confirming restricted diffusion (*). b Axial DCE-MR image (left) with corresponding time intensity curve (TIC) (right) shows peripheral enhancement of the tumor (short arrows on the left) which correlates with a type III curve (pink and orange arrows on the TIC). The blue curve in the TIC shows the typical morphology of any peripheral artery (long arrow on the left). c Axial fat-suppressed T2-weighted MR image shows hyperintensity of the bone marrow (arrows) surrounding the tumor (T), in keeping with edema. d Axial DCE-MR image (left) and corresponding TIC (right) show progressive enhancement of the bone marrow (arrows) which correlates with a type II curve (orange and pink curves), indicating edema. The blue curve in the TIC shows the typical morphology of the peripheral artery. e Axial fat-suppressed T2-weighted MR image after 2 cycles of chemotherapy shows an area of predominantly low signal intensity within the tumor (arrow) that may represent fibrosis and/or calcification. f Axial DCE-MR image (left) with corresponding TIC (right) shows progressive enhancement of the peripheral area of the tumor (short arrows) with a type II curve (red, green and pink curves), indicating overall good treatment response and presence of granulation tissue. Note the lack of enhancement of the central part of the tumor (long arrow) due to necrosis that correlates with a type I curve (orange curve) indicating non-viable tumor or necrosis. The blue curve correlates with the typical morphology of a peripheral artery