Lauren A Roller1, Ivan Chebib2, Miriam A Bredella3, Connie Y Chang4. 1. Department of Radiology, Massachusetts General Hospital, Boston, MA, USA. 2. Department of Pathology, Massachusetts General Hospital, Boston, MA, USA. 3. Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA. 4. Division of Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, MA, 02114, USA. cychang@mgh.harvard.edu.
Abstract
OBJECTIVE: To evaluate clinical and radiological features of pathology-proven extraskeletal osteosarcomas. METHODS: This retrospective study was IRB-approved and HIPAA-compliant. Our pathology database was queried for cases of extraskeletal osteosarcoma. Tumor location, size, imaging appearance, presence of metastases, and clinical outcome were documented. RESULTS: Nineteen patients met inclusion criteria (age 59 ± 15 (range 28-85) years; 15 male, 4 female). Tumors occurred in the lower extremities (12 out of 19, 63%), pelvis/gluteal region (3 out of 19, 16%), upper extremity (2 out of 19, 5%), thorax (1 out of 19, 5%), and neck (1 out of 19, 5%). Two out of 19 (11%) patients had undergone radiation to the tumor site previously. According to pathology, 16 out of 19 tumors were high-grade (84%). Tumors presented as soft-tissue masses measuring 9.5 ± 6.8 (2-29) cm. Tumor mineralization was present in 5 out of 19 cases (26%) and local invasion was found in 1 out of 19 cases (6%). On MRI, tumors typically appeared hyperintense on T2-weighted sequences with enhancement in 15 out of 15 (100%) contrast-enhanced studies, and with central necrosis in 10 out of 19 (53%) cases. Low-grade tumors were smaller (<4 cm; 3 out of 3, 100%) and lacked central necrosis (3 out of 3, 100%). 8 out of 19 patients (42%) had metastases, most commonly to the lung (7 out of 19, 37%) and bone (2 out of 19,11%). Two out of 8 patients (25%) with metastases and 8 out of 11 (73%) without metastases achieved recurrence-free survival (mean follow-up 3.8 ± 4.0 [0.2-14.2]) years. No metastases or deaths occurred in patients with low-grade histology. CONCLUSIONS: Extraskeletal osteosarcomas are rare, typically high-grade malignancies that commonly metastasize to lung and bones. Low-grade tumors and those without metastases have a good prognosis. MRI appearance is nonspecific, with T2 hyperintense signal and heterogeneous enhancement. Unlike conventional osteosarcoma, mineralization is rare.
OBJECTIVE: To evaluate clinical and radiological features of pathology-proven extraskeletal osteosarcomas. METHODS: This retrospective study was IRB-approved and HIPAA-compliant. Our pathology database was queried for cases of extraskeletal osteosarcoma. Tumor location, size, imaging appearance, presence of metastases, and clinical outcome were documented. RESULTS: Nineteen patients met inclusion criteria (age 59 ± 15 (range 28-85) years; 15 male, 4 female). Tumors occurred in the lower extremities (12 out of 19, 63%), pelvis/gluteal region (3 out of 19, 16%), upper extremity (2 out of 19, 5%), thorax (1 out of 19, 5%), and neck (1 out of 19, 5%). Two out of 19 (11%) patients had undergone radiation to the tumor site previously. According to pathology, 16 out of 19 tumors were high-grade (84%). Tumors presented as soft-tissue masses measuring 9.5 ± 6.8 (2-29) cm. Tumor mineralization was present in 5 out of 19 cases (26%) and local invasion was found in 1 out of 19 cases (6%). On MRI, tumors typically appeared hyperintense on T2-weighted sequences with enhancement in 15 out of 15 (100%) contrast-enhanced studies, and with central necrosis in 10 out of 19 (53%) cases. Low-grade tumors were smaller (<4 cm; 3 out of 3, 100%) and lacked central necrosis (3 out of 3, 100%). 8 out of 19 patients (42%) had metastases, most commonly to the lung (7 out of 19, 37%) and bone (2 out of 19,11%). Two out of 8 patients (25%) with metastases and 8 out of 11 (73%) without metastases achieved recurrence-free survival (mean follow-up 3.8 ± 4.0 [0.2-14.2]) years. No metastases or deaths occurred in patients with low-grade histology. CONCLUSIONS: Extraskeletal osteosarcomas are rare, typically high-grade malignancies that commonly metastasize to lung and bones. Low-grade tumors and those without metastases have a good prognosis. MRI appearance is nonspecific, with T2 hyperintense signal and heterogeneous enhancement. Unlike conventional osteosarcoma, mineralization is rare.
Authors: A Longhi; S S Bielack; R Grimer; J Whelan; R Windhager; A Leithner; A Gronchi; D Biau; P Jutte; A H Krieg; F M Klenke; G Grignani; D M Donati; R Capanna; J Casanova; C Gerrand; G Bisogno; S Hecker-Nolting; M De Lisa; L D'Ambrosio; M Willegger; G Scoccianti; S Ferrari Journal: Eur J Cancer Date: 2017-02-03 Impact factor: 9.162