title: Solid tumors in Turkish children: a multicenter study.
abstract: BACKGROUND
  This paper presents a detailed incidence study on childhood solid tumors comprising a histopathology-based documentation of benign and malignant lesions.
  
  
  METHODS
  The Ankara Pediatric Pathology Working Group collected databases of pediatric solid tumors from six pediatric reference centers in order to analyze the incidence, distribution and some epidemiologic characteristics of the tumors and to establish a multicenter database for further studies. A five-year retrospective archive search was carried out. Excluding epithelial tumors of the skin, leukemia, lymphoreticular system neoplasias, metastatic tumors, and hamartomas, 1362 solid tumors in 1358 patients were classified according to age, sex, localization, histopathology and clinical behavior.
  
  
  RESULTS
  The male/female ratio was 0.9; 14.8% (201) of the patients belonged to 0-1 year age group, 20.7% (281) to 2-4 years, 25.9% (352) to 5-10 years, 22.2% (301) to 11-14 years, and 16.4% (223) to 15-18 years. Among all tumors, 708 (52.0%) were malignant, 645 (47.4%) benign tumors, 2 (0.1%) borderline tumors, and 2 (0.1%) unknown behavioral tumors. Malignant tumors were found in 50.2% (357) of female patients and in 54.0% (349) of male patients. A balanced distribution between benign and malignant entities among children under 18 years was observed. Comparison between the age groups revealed malignant cases outnumbered benign cases under 4 years of age while benign tumor numbers increased after 10 years of age. The most common entities in the malignant group were of sympathetic nervous system origin, while soft tissue tumors far outnumbered the others in the benign group.
  
  
  CONCLUSIONS
  We conclude that the cancer patterns of children in the Ankara region mostly resemble with those of the western population. This study provides useful information on the diagnosis of solid tumors in children and highlights variations in cancer incidence in different age groups.
authors: Pathology Department, Ankara Child Diseases Hematology Oncology Research and Training Hospital, Ankara, Turkey. ayperkacar@yahoo.com
authors: Ayper
authors: A
authors: Kacar
authors: Irem
authors: I
authors: Paker
authors: Zuhal
authors: Z
authors: Akcoren
authors: Safak
authors: S
authors: Gucer
authors: Gulsev
authors: G
authors: Kale
authors: Diclehan
authors: D
authors: Orhan
authors: Beril
authors: B
authors: Talim
authors: Aylar
authors: A
authors: Poyraz
authors: Omer
authors: O
authors: Uluoglu
authors: Aylin Okcu
authors: AO
authors: Heper
authors: Sema
authors: S
authors: Apaydin
authors: Nilufer
authors: N
authors: Arda
authors: Esin
authors: E
authors: Boduroglu
authors: Aynur
authors: A
authors: Albayrak
authors: Murat
authors: M
authors: Alper
authors: Ata Turker
authors: AT
authors: Arikok
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009369:Neoplasms / Q000453:epidemiology*; D012189:Retrospective Studies; D014421:Turkey