title: Preoperative easily misdiagnosed telangiectatic osteosarcoma: clinical-radiologic-pathologic correlations.
abstract: OBJECTIVE
  To describe the clinical, imaging, and pathologic characteristics and diagnostic methods of telangiectatic osteosarcoma (TOS) for improving the diagnostic level.
  
  
  METHODS
  The authors retrospectively reviewed patient demographics, serum alkaline phosphatase (AKP) levels, preoperative biopsy pathologic reports, pathologic materials, imaging findings, and treatment outcomes from 26 patients with TOS. Patient images from radiography (26 cases) and magnetic resonance (MR) imaging (22 cases) were evaluated by 3 authors in consensus for intrinsic characteristics. There were 15 male and 11 female patients in the study, with an age of 9-32 years (mean age 15.9 years).
  
  
  RESULTS
  Eighteen of 26 patients died of lung metastases within 5 years of follow-up. The distal femur was affected more commonly (14 cases, 53.8%). Regarding serum AKP, normal (8 cases) or mildly elevated (18 cases) levels were found before preoperative chemotherapy. Radiographs showed geographic bone lysis without sclerotic margin (26 cases), cortical destruction (26 cases), periosteal new bone formation (24 cases), soft-tissue mass (23 cases), and matrix mineralization (4 cases). The aggressive radiographic features of TOS simulated the appearance of conventional high-grade intramedullary osteosarcoma, though different from aneurysmal bone cyst. MR images demonstrated multiple big (16 cases) or small (6 cases) cystic spaces, fluid-fluid levels (14 cases), soft-tissue mass (22 cases), and thick peripheral and septal enhancement (22 cases). Nine of 26 cases were misdiagnosed as aneurysmal bone cysts by preoperative core-needle biopsy, owing to the absence of viable high-grade sarcomatous cells in the small tissue samples.
  
  
  CONCLUSIONS
  The aggressive growth pattern with occasional matrix mineralization, and multiple big or small fluid-filled cavities with thick peripheral, septal, and nodular tissue surrounding the fluid-filled cavities are characteristic imaging features of TOS, and these features are helpful in making the correct preoperative diagnosis of TOS.
authors: Department of Radiology, First Affiliated Hospital of Sun Yat-sen University, 510080 Guangzhou, China.
authors: Zhen-Hua
authors: ZH
authors: Gao
authors: Department of Orthopedics, First Affiliated Hospital of Sun Yat-sen University, 510080 Guangzhou, China.
authors: Jun-Qiang
authors: JQ
authors: Yin
authors: Department of Pathology, First Affiliated Hospital of Sun Yat-sen University, 510080 Guangzhou, China.
authors: Da-Wei
authors: DW
authors: Liu
authors: Department of Radiology, First Affiliated Hospital of Sun Yat-sen University, 510080 Guangzhou, China.
authors: Quan-Fei
authors: QF
authors: Meng
authors: Department of Radiology, First Affiliated Hospital of Sun Yat-sen University, 510080 Guangzhou, China.
authors: Jia-Ping
authors: JP
authors: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000473:pathology; D002648:Child; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D012516:Osteosarcoma / Q000175:diagnosis* / Q000473:pathology; D012189:Retrospective Studies