title: Pattern of primary tumors and tumor-like lesions of bone in children: retrospective survey of biopsy results.
abstract: BACKGROUND
  Although primary bone tumors are relatively uncommon, they constitute the most important tumors in patients less than 20 years. We aimed to determine the frequencies of primary bone tumors and tumor-like lesions of bone and the anatomical sites of their occurrence.
  
  
  METHODS
  A retrospective review of histopathology reports of all bone specimens received in a private pathology laboratory in Istanbul between 2009 and 2015.
  
  
  RESULTS
  A total of 57 patients (aged 5 to 18 years) with a mean of 13.12 years were studied. Thirty five patients (61.4%) were males and 22 (38.6%) were females. Fifty five (94.4%) of the tumors were benign. Osteochondroma was the commonest tumor accounting for 31 cases (54.3%) followed by osteoid osteoma, 9 cases (15.7%). Chondrosarcoma observed in two patients and Ewing sarcoma in one patient as malignant tumors. Of the 57 bone tumors 13 (22.8%) occurred in the upper extremities, while 44 (77.2%) were in the lower extremities. Proximal humerus was the most commonly involved site in upper extremity tumors, with osteochondromas representing the most frequent type of tumor (4 patients; 7%). In the lower extremities again osteochondromas were the most common type of tumor (8 cases, 14%), with the femur being the most common site of involvement (18 patients, 31.5%). Of the patients with tumor-like lesions; four patients had fibrous dysplasia, 4 patients had non-ossified fibromas, 4 patients had simple bone cysts and 3 had aneurismal bone cyst.
  
  
  CONCLUSIONS
  This study showed that primary bone tumors were mainly benign, settled predominantly in the lower extremities mostly in the femur with a male preponderance. Osteochondroma was the most common benign bone tumor. We didn't observed osteosarcoma, which is the most frequent malignant bone tumor.
authors.affiliation: Department of Pediatrics, Bozok University Medical Faculty Yozgat, Turkey.
authors.forename: Esra Akyüz
authors.initials: EA
authors.lastname: Özkan
authors.affiliation: Department of Pathology, Haydarpasa Numune Training and Research Hospital Istanbul.
authors.forename: Ceren Canbey
authors.initials: CC
authors.lastname: Göret
authors.affiliation: Department of Internal Medicine, Bozok University Medical Faculty Yozgat, Turkey.
authors.forename: Zeynep Tuğba
authors.initials: ZT
authors.lastname: Özdemir
authors.affiliation: Department of Pathology, Iskenderun State Hospital Hatay, Turkey.
authors.forename: Serdar
authors.initials: S
authors.lastname: Yanık
authors.affiliation: Department of Pathology, Atatürk University Medical Faculty Erzurum, Turkey.
authors.forename: Meryem
authors.initials: M
authors.lastname: Doğan
authors.affiliation: Department of Pathology, Tekirdağ State Hospital Tekirdağ, Turkey.
authors.forename: Aylin
authors.initials: A
authors.lastname: Gönültaş
authors.affiliation: Department of Family Medicine, Iskenderun State Hospital Hatay, Turkey.
authors.forename: Ayşe Neslin
authors.initials: AN
authors.lastname: Akkoca
mesh_terms: D000293:Adolescent; D001706:Biopsy; D001859:Bone Neoplasms / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D002813:Chondrosarcoma / Q000473:pathology*; D005260:Female; D006801:Humans; D006811:Humerus / Q000473:pathology; D008297:Male; D015831:Osteochondroma / Q000473:pathology*; D012189:Retrospective Studies; D012512:Sarcoma, Ewing / Q000473:pathology*; D011795:Surveys and Questionnaires; D014421:Turkey
keywords: Benign; bone tumors; malignant; pediatric