title: Analysis of RAS mutation and PAX8/PPARγ rearrangements in follicular-derived thyroid neoplasms in a Korean population: frequency and ultrasound findings.
abstract: OBJECTIVE
  To investigate the frequency and ultrasonography (US) findings of RAS mutations and PAX8/PPARγ rearrangements between follicular thyroid adenomas (FTAs) and follicular thyroid carcinomas (FTCs) in a Korean population.
  
  
  METHODS
  RAS mutations and PAX8/PPARγ rearrangements in 56 FTAs and 35 FTCs were analyzed. We also analyzed the US findings of FTCs and FTAs.
  
  
  RESULTS
  16 nodules of 35 FTCs (45.7 %) and 19 nodules of 56 FTAs (33.9 %) harbored RAS mutations. Three FTCs and three FTAs showed two point mutations simultaneously. K-RAS codon 12-13 (n = 6, 31.6 %), N-RAS codon 61 (n = 5, 26.3 %), H-RAS codon 61 (n = 4, 21.1 %), K-RAS codon 61 (n = 3, 15.8 %), and N-RAS codon 12-13 (n = 1, 5.3 %) were found in FTCs, and N-RAS codon 61 (n = 10, 45 %), K-RAS codon 12-13 (n = 5, 22.7 %), H-RAS codon 61 (n = 5, 22.7 %), K-RAS codon 61 (n = 1, 4.5 %), and N-RAS codon 12-13 (n = 1, 4.5 %) were observed in FTAs. 4 of 56 (7.1 %) FTAs and 1 of 35 (2.9 %) FTCs represented PAX8/PPARγ rearrangements, respectively (P = 0.645). The absence of a hypoechoic rim (P = 0.021) and presence of calcifications (P = 0.049) were significantly associated with FTCs compared with FTAs.
  
  
  CONCLUSIONS
  RAS mutation frequency targeting the Korean population showed a 45.7 % in FTCs and 35.7 % in FTAs, and PAX8/PPARγ rearrangements were more frequently showed in FTAs. K-RAS codon 12-13 was the most common RAS mutation in FTCs, whereas N-RAS codon 61 was more frequent in FTAs. The presence of calcifications and absence of a hypoechoic rim showed more frequently in FTCs.
authors.affiliation: Department of Radiology, Soonchunhyang University Bucheon Hospital, 170 Jomaru-ro, Wonmi-gu, Bucheon, Gyeonggi-do, 420-767, Republic of Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Jeong
authors.forename: H S
authors.initials: HS
authors.lastname: Hong
authors.forename: J J
authors.initials: JJ
authors.lastname: Kwak
authors.forename: E H
authors.initials: EH
authors.lastname: Lee
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000175:diagnosis / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000235:genetics*; D002648:Child; D005260:Female; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D000072636:PAX8 Transcription Factor; D047495:PPAR gamma / Q000235:genetics*; D051761:Paired Box Transcription Factors / Q000235:genetics*; D011159:Population Surveillance; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000235:genetics*; D055815:Young Adult
chemical_list: D000072636:PAX8 Transcription Factor; C083325:PAX8 protein, human; D047495:PPAR gamma; D051761:Paired Box Transcription Factors