case_images: PMC8313319_01
case_images: Chondrosarcoma in a 75-year-old woman. A plain radiograph showing a poorly specific finding in the sacrum (A). Computed tomography showing destruction of the bone in the left posterior ilium (arrow) ((B), top). The anterior cortex of the S1 vertebra was scalloped (arrow) ((B), bottom). Magnetic resonance imaging shows a lobulated lesion with homogenous low signal intensity on a T1-weighted image ((C), top) and high signal intensity on a T2-weighted image. The septal structure of each lobulated lesion had slightly low signal intensity on T2-weighted imaging ((C), bottom). The tumor is protuberant with a dumbbell shape in the enlarged S1 anterior foramen (arrows) (C). Plain postoperative X-ray radiograph, showing fixation of the L5-S-ilium (D).
case_images: CRIOR2021-5510075.001.jpg
case_images: PMC8313319_01_CRIOR2021-5510075.001.jpg
case_images: fig1
case_images: A plain radiograph of the sacrum showed a slight abnormality of irregular cortex of the first sacral (S1) vertebra to the ala (Figure 1(A)). The destruction was less obvious in the anterior cortex of the S1 vertebra, and the cortex was scalloped with remodeling, which is characteristic of benign bone lesions (Figure 1(B)). Furthermore, the tumor extended along the S1 nerve root to the anterior sacrum, with the shape of a dumbbell in the enlarged S1 anterior foramen (Figure 1(C)). The defect at the left sacroiliac joint was filled with a low-porosity beta-tricalcium phosphate (TCP) block, which has strong compression resistance (OSferion60; Olympus Terumo Biomaterials, Tokyo, Japan) (Figure 1(D)).
case_images: Grade I chondrosarcoma, moderately cellular and containing hyperchromatic, plump nuclei of uniform size (a). Infiltration through the marrow cavity with a "permeation pattern" is seen (b).
case_images: CRIOR2021-5510075.002.jpg
case_images: PMC8313319_01_CRIOR2021-5510075.002.jpg
case_images: fig2
case_images: The final histopathological diagnosis of the resected material was conventional chondrosarcoma, grade I (Figure 2).
case_images: As of 10 months after the surgery, computed tomography shows no recurrence of the tumor and no dislocation of the implants including the beta-tricalcium phosphate (yellow arrows): (A) sagittal; (B) coronal; (C) axial.
case_images: CRIOR2021-5510075.003.jpg
case_images: PMC8313319_01_CRIOR2021-5510075.003.jpg
case_images: fig3
case_images: No recurrence of the tumor was seen 10 months after the surgery (Figure 3).