title: Concordance between PIK3CA mutations in endoscopic biopsy and surgically resected specimens of esophageal squamous cell carcinoma.
abstract: PIK3CA mutations are expected to be potential therapeutic targets for esophageal squamous cell carcinoma (ESCC). We aimed to clarify the concordance between PIK3CA mutations detected in endoscopic biopsy specimens and corresponding surgically resected specimens.
  
  
  
  We examined five hotspot mutations in the PIK3CA gene (E542K, E545K, E546K, H1047R, and H1047L) in formalin-fixed and paraffin-embedded tissue sections of paired endoscopic biopsy and surgically resected specimens from 181 patients undergoing curative resection for ESCC between 2000 and 2011 using a Luminex technology-based multiplex gene mutation detection kit.
  
  
  
  Mutation analyses were successfully performed for both endoscopic biopsy and surgically resected specimens in all the cases. A PIK3CA mutation was detected in either type of specimen in 13 cases (7.2%, 95% confidence interval: 3.9-12.0). The overall concordance rate, positive predictive value, and negative predictive value were 98.3% (178/181), 90.9% (10/11), and 98.8% (168/170), respectively. Among patients with a PIK3CA mutation detected in both types of specimens, the concordance between PIK3CA mutation genotypes was 100%. There were three cases with a discordant mutation status between the types of specimens (PIK3CA mutation in surgically resected specimen and wild-type in biopsy specimen in two cases, and the opposite pattern in one case), suggesting possible intratumoral heterogeneity in the PIK3CA mutation status.
  
  
  
  The PIK3CA mutation status was highly concordant between endoscopic biopsy and surgically resected specimens from the same patient, suggesting that endoscopic biopsy specimens can be clinically used to detect PIK3CA mutations in patients with ESCC.
authors.affiliation: Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan.|Division of Pathology, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Chiba, Japan.|Department of Medical Oncology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Hatogai
authors.affiliation: Division of Pathology, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Chiba, Japan. sfujii@east.ncc.go.jp.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fujii
authors.affiliation: Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kojima
authors.affiliation: Department of Esophageal Surgery, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Daiko
authors.affiliation: Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Doi
authors.affiliation: Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan.|Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ohtsu
authors.affiliation: Division of Pathology, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Chiba, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ochiai
authors.affiliation: Department of Medical Oncology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Takiguchi
authors.affiliation: Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan. tyoshino@east.ncc.go.jp.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yoshino
mesh_terms: D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000556:secondary / Q000601:surgery; D058534:Class I Phosphatidylinositol 3-Kinases / Q000235:genetics*; D004252:DNA Mutational Analysis; D004724:Endoscopy; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D016629:Esophagectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics; D015996:Survival Rate
chemical_list: D058534:Class I Phosphatidylinositol 3-Kinases; D018719:Erb-b2 Receptor Tyrosine Kinases; C484760:PIK3CA protein, human
keywords: Concordance; Endoscopic biopsy; Esophageal squamous cell carcinoma; PIK3CA gene