title: Occult trauma mimicking metastases on bone scans in pediatric oncology patients.
abstract: BACKGROUND
  Tracer-avid osseous lesions are usually considered to represent metastases in pediatric oncology patients. However, sites of minor, clinically occult, skeletal trauma may be mistaken for osseous metastases.
  
  
  OBJECTIVE
  The objective of this study was to review our experience with skeletal scintigraphy in pediatric oncology patients to determine specificity for metastatic disease. Materials and methods. We reviewed 164 bone scans performed on 96 consecutive patients (ages 5 months to 23 years) at presentation with malignancy or during chemotherapy. Tumors included osteosarcoma (13), Ewing sarcoma (11), lymphoma (19), neuroblastoma (12), brain tumors (16), rhabdomyosarcoma (10), renal tumors (5), and miscellaneous neoplasms (10). Scintigraphic abnormalities were considered metastatic based on radiographic findings, subsequent tumor progression, or multiplicity of lesions. Lesions were considered benign when spontaneous resolution occurred without change in therapy or radiographs demonstrated a traumatic or other benign lesion.
  
  
  RESULTS
  Of the 96 patients, 51 had normal studies or showed only the primary lesion. Of the 45 patients with abnormal scintigraphy, 16 (35 %) had metastases and 29 (65 %) had one or more focal benign lesions. These lesions included abnormalities due to stress/trauma (25), benign neoplasm (2), infection (3), disuse (6), surgery (10) and artifacts (4).
  
  
  CONCLUSIONS
  The majority of scintigraphic abnormalities have nonmalignant etiologies, most commonly stress reaction and trauma. In patients without known extraosseous metastases, one or two skeletal lesions should not be assumed to represent metastatic disease.
authors.affiliation: University of Texas Southwestern Medical Center and Children's Medical Center of Dallas, 1935 Motor Street, Dallas, Texas, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Lowry
authors.forename: M C
authors.initials: MC
authors.lastname: Carstens
mesh_terms: D000293:Adolescent; D000328:Adult; D016477:Artifacts; D001847:Bone Diseases / Q000000981:diagnostic imaging / Q000382:microbiology; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000293:injuries / Q000601:surgery; D001932:Brain Neoplasms / Q000000981:diagnostic imaging; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D018450:Disease Progression; D050723:Fractures, Bone / Q000000981:diagnostic imaging*; D015775:Fractures, Stress / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging; D008223:Lymphoma / Q000000981:diagnostic imaging; D009447:Neuroblastoma / Q000000981:diagnostic imaging / Q000556:secondary; D010019:Osteomyelitis / Q000000981:diagnostic imaging / Q000382:microbiology; D012516:Osteosarcoma / Q000000981:diagnostic imaging / Q000556:secondary; D011859:Radiography; D011877:Radionuclide Imaging; D012075:Remission, Spontaneous; D012208:Rhabdomyosarcoma / Q000000981:diagnostic imaging / Q000556:secondary; D012512:Sarcoma, Ewing / Q000000981:diagnostic imaging / Q000556:secondary