title: Oncologic manifestations of neurofibromatosis type 1 in Korea.
abstract: OBJECTIVE
  The aim of this study was to investigate the incidence and spectrum of malignant tumors in Korean neurofibromatosis type 1 (NF1) patients.
  
  
  METHODS
  We retrospectively reviewed 125 patients who were diagnosed with NF1 at a single institution from 1995 to 2010. The incidence, location, histologic type, and radiologic findings of malignant tumors as well as development of multiple primary tumors were analyzed.
  
  
  RESULTS
  Eighteen malignant tumors occurred in 16 patients (12.8%) among 125 Korean NF1 patients; 9 carcinomas, 8 sarcomas and 1 central nervous system (CNS) tumor. Five tumors were of nervous system origin and 13 were non-nervous system tumors. The locations of the tumors were as follow: 1 CNS, 2 lung, 3 breast, 3 stomach, 3 small bowel, 1 colon, 1 liver, 1 uterus, 1 neck, and 2 in extremities. Three malignant peripheral nerve sheath tumors (MPNSTs) occurred at the neck and extremity, and one in the liver. All three gastrointestinal stromal tumors (GISTs) had multiple tumors in the jejunum, and one MPNST and one pheochromocytoma were accompanied in two GISTs. Multiple primary tumors, benign or malignant were reported in 4 patients (25.0%), synchronously or metachronously.
  
  
  CONCLUSIONS
  Korean NF1 patients had a high risk of developing malignant tumors. The common malignant tumors in Koreans such as breast, lung and stomach cancers developed frequently in addition to the NF1-related tumors such as MPNST or GIST.
authors.affiliation: Department of Surgery, Dankook University College of Medicine, Cheonan, Korea.
authors.forename: Eui Tae
authors.initials: ET
authors.lastname: Kim
authors.forename: Hwan
authors.initials: H
authors.lastname: Namgung
authors.forename: Hyun Deok
authors.initials: HD
authors.lastname: Shin
authors.forename: Soon Il
authors.initials: SI
authors.lastname: Lee
authors.forename: Jee Eun
authors.initials: JE
authors.lastname: Kwon
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Chang
authors.forename: Dong Guk
authors.initials: DG
authors.lastname: Park