J Cui1, X Xia2, N Tian3, S Sun4, X Sui1, C Gao1, X Liu5. 1. Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China. 2. Department of Radiology, Qilu Hospital of Shandong University, Qingdao, Shandong, China. 3. Department of Endocrinology and Metabolism, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China. 4. Department of Precision Medicine Center of Oncology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China. 5. Department of Gastrointestinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China. Electronic address: mariotg@163.com.
Abstract
AIM: To test the hypothesis that computed tomography (CT) and magnetic resonance imaging (MRI) could help distinguish between giant cell tumours with prominent aneurysmal bone cysts (GABCs) and primary aneurysmal bone cysts (PABCs) of the extremities. MATERIALS AND METHODS: CT and MRI features of 13 patients with GABCs and 13 patients with PABCs in the extremities were analysed retrospectively. The ages and sex of the patients were also recorded. Independent-samples t-tests were used for continuous variables and Fisher's exact tests were used for categorical variables to compare the differences between the two groups. Diagnostic accuracy, sensitivity, and interobserver agreement were calculated. RESULTS: The average age of patients with GABCs (38.2±15.8 years) was higher than that of patients with PABCs (19.3±12.7 years; p=0.003). The transverse/longitudinal diameter ratio was different between GABCs (0.8±0.3) and PABCs (0.6±0.2; p=0.007). Subchondral bone involvement (92.3% versus 30.8%, p=0.004) and deep lobulation (38.5% versus 0%, p=0.039) were more likely to be noted in patients with GABCs. Surrounding blood vessels were identified in six cases of PABCs (6/13), but not in GABCs (p=0.015). The following characteristics were suggestive of GABCs, older patient age, higher transverse/longitudinal diameter ratio, subchondral bone involvement, and deep lobulation indicated a sensitivity of 84.6%, 76.9%, 75%, and 100%, and a specificity of 84.6%, 69.2%, 90%, and 61.9%, respectively. Conversely, surrounding blood vessels were suggestive of PABCs, with a sensitivity of 46.2% and specificity of 100%. The concordance between the two readers was moderate to nearly perfect. CONCLUSION: Age, subchondral bone involvement, lobulation, transverse/longitudinal diameter ratio, and surrounding blood vessels can be used to distinguish GABCs from PABCs.
AIM: To test the hypothesis that computed tomography (CT) and magnetic resonance imaging (MRI) could help distinguish between giant cell tumours with prominent aneurysmal bone cysts (GABCs) and primary aneurysmal bone cysts (PABCs) of the extremities. MATERIALS AND METHODS: CT and MRI features of 13 patients with GABCs and 13 patients with PABCs in the extremities were analysed retrospectively. The ages and sex of the patients were also recorded. Independent-samples t-tests were used for continuous variables and Fisher's exact tests were used for categorical variables to compare the differences between the two groups. Diagnostic accuracy, sensitivity, and interobserver agreement were calculated. RESULTS: The average age of patients with GABCs (38.2±15.8 years) was higher than that of patients with PABCs (19.3±12.7 years; p=0.003). The transverse/longitudinal diameter ratio was different between GABCs (0.8±0.3) and PABCs (0.6±0.2; p=0.007). Subchondral bone involvement (92.3% versus 30.8%, p=0.004) and deep lobulation (38.5% versus 0%, p=0.039) were more likely to be noted in patients with GABCs. Surrounding blood vessels were identified in six cases of PABCs (6/13), but not in GABCs (p=0.015). The following characteristics were suggestive of GABCs, older patient age, higher transverse/longitudinal diameter ratio, subchondral bone involvement, and deep lobulation indicated a sensitivity of 84.6%, 76.9%, 75%, and 100%, and a specificity of 84.6%, 69.2%, 90%, and 61.9%, respectively. Conversely, surrounding blood vessels were suggestive of PABCs, with a sensitivity of 46.2% and specificity of 100%. The concordance between the two readers was moderate to nearly perfect. CONCLUSION: Age, subchondral bone involvement, lobulation, transverse/longitudinal diameter ratio, and surrounding blood vessels can be used to distinguish GABCs from PABCs.