Chondrosarcoma: A Clinical Review

Abstract

Chondrosarcomas are a diverse group of malignant cartilaginous matrix-producing neoplasms. Conventional chondrosarcomas are a continuum of disease based on the biologic activity of the tumor. The tumors range from the relatively biologically benign low-grade tumors or intermediate atypical cartilaginous tumors (ACTs), to malignant, aggressive high-grade tumors. The clinical presentation, radiographic and pathologic findings, treatments and outcomes vary significantly based on the histologic grade of the tumor. Chondrosarcomas present a diagnostic dilemma, particularly in the differentiation between high- and intermediate-grade tumors and that of low-grade tumors from benign enchondromas. A multidisciplinary team at a tertiary sarcoma centre allows for optimal care of these patients.

Keywords: chondrosarcoma; review; sarcoma.

Figure 1

Radiograph (A) of the left proximal humerus demonstrates subtle lucency with internal stippled calcified foci (yellow arrow), in keeping with chondroid matrix. Subtle endosteal scalloping is present (white arrows) without cortical breakthrough or periosteal reaction. Sagittal (B) and axial (C) T2-weighted images with fat saturation of the same patient demonstrating a lobulated T2 hyperintense mass. A few stippled areas of low signal intensity represent chondroid matrix (white arrow). The lesion measures greater than 5 cm in length. Axial images demonstrate endosteal scalloping at the anterolateral border. No periostitis or cortical breakthrough. Imaging features are in keeping with an atypical cartilaginous tumor, which was confirmed on pathology after surgical curettage.

Figure 2

AP (A) and lateral (B) radiographs demonstrate an aggressive, heterogenous lytic lesion in the left proximal humerus with a wide zone of transition (white arrows). The lesion measures greater than 5 cm in length. Chondroid matrix is demonstrated. Periosteal reaction is present at the lateral aspect. There is a large area of cortical breakthrough at the anterior cortex, in addition to numerous areas of endosteal scalloping. Computed tomography (C) further demonstrates the cortical disruption and chondroid matrix formation (white arrow).

Figure 3

Axial (A) and coronal (B) T2-weighted, fat-saturated MR images of the same patient in Figure 2 confirm present of a chondroid lesion (yellow circle) with aggressive features, including cortical breakthrough (white arrow) and numerous areas of endosteal scalloping (yellow arrow). There is a significant amount of extra-osseous chondroid tumor. Perilesional edema (red arrow) is seen extending into the adjacent soft tissues.

Figure 4

Microscopic images showing cartilaginous matrix-producing tumor (*) with permeation into the bone (1(A) H&E ×100; arrow) and entrapping the pre-existing lamellar bone (1(B) H&E ×200).

Figure 5

Microscopic images. Chondrosarcoma grading is based on the cellularity, cellular and nuclear pleomorphism/atypia and mitotic activity (H&E ×200). Grade 1/ACT is characterized by mild cellular atypia with small chondrocytes and nuclei. Grade 2 tumors are marked by increasing cellular atypia, increased nuclear size and binucleated cells. Grade 3 tumors are marked cellular atypia with nuclear enlargement and polymorphism.