A reproducible and simple grading system for classical chondrosarcomas. Analysis of 35 chondrosarcomas and 16 enchondromas with emphasis on recurrence rate and radiological and clinical data

Abstract

In the past, six histological grading systems for classical chondrosarcoma have been published. Due to the inhomogeneity and complexity of these classifications, the comparison of clinical data, survival rates and local failures has to be considered critically. In 1996, the author published a grading system that was simple to use and easily reproduced. This system was based on a few nuclear features. The main intention of the current study was to verify whether the histological grade, which was defined by the author's classification, correlates with the recurrence rate. In a retrospective study, clinical data, X-rays and histological material from 35 patients with classical chondrosarcoma and 16 patients with enchondroma were analysed. Statistical analysis was done using the chi-squared test and the Fisher exact test. Local recurrence occurred in 25.7% of all patients. The difference in recurrence rate among grades 1-3 was statistically significant ( P=0.002). The frequency of grades 1-3 varied up to 54%, when published grading systems were compared. No significant difference between the histological grade and features such as double nuclei and mitosis were observed. The frequency of cellularity, double nuclei and mitoses was similar between enchondromas and low-grade chondrosarcomas. Of chondrosarcoma patients, 90.6% of total patients and 87.5% of those with grade-1 lesions reported pain, whereas only 43.8% of the enchondroma patients did. Even in patients with grade-1 chondrosarcomas, radiological findings were much more aggressive in comparison with enchondromas. The histological grade, defined on the basis of the author's simple and reproducible grading system, indicates the risk of local recurrence, especially in cases that are inadequately treated. Grade-3 chondrosarcomas and lesions located in regions where the removal of the tumour would be difficult have to be given special attention.

Differentiating high-grade from low-grade chondrosarcoma with MR imaging

“…The role of plain radiography is limited in this context [13,14]. So far, most studies have been concerned with making a radiological distinction between low-grade chondrosarcoma and enchondroma [1][2][3][4][5]. To the best of our knowledge, however, only a few reports have described high-grade chondrosarcomas (HGCS) on MR imaging, and the differentiation between low-grade chondrosarcoma (LGCS) and HGCS has not been sufficiently described and discussed [15][16][17].…”

“…There were several MR imaging features of chondrosarcoma that could be helpful in distinguishing HGCS from LGCS. Among them, soft Introduction A chondrosarcoma is the second most common primary malignant bone tumour, characterised by the production of cartilage [1][2][3][4][5]. Based on the presence of cellular atypia, mitotic figures and cellularity, chondrosarcomas are classified into three histological grades [1,2,6,7].…”

“…Among them, soft Introduction A chondrosarcoma is the second most common primary malignant bone tumour, characterised by the production of cartilage [1][2][3][4][5]. Based on the presence of cellular atypia, mitotic figures and cellularity, chondrosarcomas are classified into three histological grades [1,2,6,7]. It is known that risk of local recurrence, metastatic spread and mortality increases with the presence of high-grade tumours [8][9][10][11][12].…”

Chondrogene Tumoren des Skeletts

“…Der lobuläre Tumoraufbau geht mehr und mehr verloren [24]. Basierend auf diesen Befunden können Chondrosarkome in 3 Malignitätsgrade eingeteilt werden [25]. Dies hat prognostische Bedeutung, da Grad-1-Chondrosarkome praktisch nur zu Rezidiven neigen, wäh-rend Grad-2-(bis 20%) und Grad-3-Sarkome (bis 50%) zunehmend Metastasen entwickeln [8].…”

Molecular Imaging of Cartilage

“…High-grade tumors do not have septations and show diffuse, heterogeneous enhancement. Low-grade lesions show a lobulated pattern with enhanced septations after intravenous injection of contrast medium but cannot be easily differentiated from benign chondroma (14). Even if size, radiologic aspect, and location are known, biopsy is mandatory (15,16).…”