Concordance between Radiological Features and Histopathological Diagnosis of Cartilaginous Lesions of Bone among Patients at a Tertiary Care Centre, Trivandrum, Kerala

Abstract

Introduction: Cartilaginous tumours comprise a large, heterogeneous group of mesenchymal neoplasms. They pose a challenge in terms of accurate diagnosis and management. Histopathological findings have direct implications for treatment outcomes. Aim: To determine the concordance between the radiological features and the histopathological diagnosis of cartilaginous lesions of bone. Materials and Methods: This was a retrospective study conducted in the Department of Pathology, Regional Cancer Centre, Trivandrum, Kerala, India, among 109 patients with histopathologically proven benign and malignant cartilaginous tumours, received in the laboratory between January 2012 and December 2021 for a duration of 10 years, were analysed. The study was conducted between September 2019 and January 2022. The demographic data for the study, including age, tumour site, clinical findings, and radiological diagnosis, were obtained from medical records. The cases were histopathologically graded based on the World Health Organization 2020 classification of tumours of soft tissue and bone. The concordance between histopathological diagnosis and radiological features was assessed. The Chi-square test was used to find the association between two categorical variables, and the Independent sample t-test was used to find the difference between two groups with respect to mean and standard deviation. Results: There were a total of 109 cases of cartilaginous tumours, out of which 82 cases (75.22%) were diagnosed as malignant and 27 cases (24.77%) were diagnosed as benign. Among benign neoplasms, chondroblastoma and osteochondroma were the most common, with 10 cases (37.03%) each. Among malignant chondroid tumours, 73 (89.02%) were diagnosed as conventional chondrosarcoma. There were five cases (6.09%) of secondary chondrosarcomas (malignant transformation of a benign cartilaginous lesion). Among the secondary chondrosarcomas, three cases (60%) were malignant transformation in osteochondroma, 1 (20%) in enchondroma, and 1 (20%) in synovial chondromatosis. Among the 91 cases for which radiology was available, 86 (94.50%) had a concordance between radiological and histopathological diagnosis. Five cases (5.49%) had a discordant radiological diagnosis. Conclusion: For histologically benign tumours, the radiological findings in the study were identical and concordant. For histologically malignant tumours, there were discrepancies with radiological findings in this study when the lesion had an associated cyst, absence of cortical destruction, or absence of a clear cartilaginous component and extra cortical expansion. For histologically suspicious cases in the study, the final diagnosis was made based upon radiological findings, with a particular interest in cortical destruction.