title: Associations between mutations and histologic patterns of mucin in lung adenocarcinoma: invasive mucinous pattern and extracellular mucin are associated with KRAS mutation.
abstract: Multiple reports indicate that epidermal growth factor receptor (EGFR) mutations are associated with lepidic-pattern lung adenocarcinoma and that KRAS mutations are associated with invasive mucinous adenocarcinoma. We sought to investigate the association between EGFR and KRAS mutations and specific morphologic characteristics, such as predominant histologic subtype and mucinous features. Clinical data for 864 patients with resected lung adenocarcinoma that underwent molecular testing for EGFR and KRAS mutations were collected. Histologic subtyping was performed according to the IASLC/ATS/ERS lung adenocarcinoma classification, with attention given to signet-ring cell feature and extracellular mucin. EGFR mutations were detected using a polymerase chain reaction-based sizing assay, KRAS mutations were detected using Sanger sequencing, and ALK expression was detected using immunohistochemistry. Invasive mucinous adenocarcinoma was associated with KRAS mutation (P<0.001). Among invasive mucinous adenocarcinomas with KRAS mutation, a pure mucinous pattern was more common than a mixed mucinous/nonmucinous pattern (P=0.002). Invasive mucinous adenocarcinoma was associated with KRAS transition mutations (G→A) but not transversion mutations (G→T or G→C) compared with nonmucinous tumors (P=0.009). The lepidic-predominant group was associated with EGFR mutation compared with nonlepidic-predominant tumors (P=0.011). Extracellular mucin was associated with KRAS mutation (P<0.001), whereas signet-ring cell feature was not associated with EGFR or KRAS mutation (P=0.517). ALK expression was associated with signet-ring cell feature (P=0.001) but not with extracellular mucin (P=0.089). Our study shows that histologic patterns of mucin in lung adenocarcinoma-including invasive mucinous adenocarcinoma and extracellular mucin-are associated with KRAS mutation.
authors.affiliation: *Department of Surgery, Division of Thoracic Service §Department of Medicine, Thoracic Oncology Service, Division of Solid Tumor Oncology Departments of †Pathology ∥Epidemiology and Biostatistics ¶Center for Cell Engineering, Memorial Sloan-Kettering Cancer Center, New York, NY ‡Faculty of Medicine, Department of Diagnostic Pathology, Kagawa University, Kagawa, Japan.
authors.forename: Kyuichi
authors.initials: K
authors.lastname: Kadota
authors.forename: Yi-Chen
authors.initials: YC
authors.lastname: Yeh
authors.forename: Sandra P
authors.initials: SP
authors.lastname: D'Angelo
authors.forename: Andre L
authors.initials: AL
authors.lastname: Moreira
authors.forename: Deborah
authors.initials: D
authors.lastname: Kuk
authors.forename: Camelia S
authors.initials: CS
authors.lastname: Sima
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Riely
authors.forename: Maria E
authors.initials: ME
authors.lastname: Arcila
authors.forename: Mark G
authors.initials: MG
authors.lastname: Kris
authors.forename: Valerie W
authors.initials: VW
authors.lastname: Rusch
authors.forename: Prasad S
authors.initials: PS
authors.lastname: Adusumilli
authors.forename: William D
authors.initials: WD
authors.lastname: Travis
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D000077192:Adenocarcinoma of Lung; D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004252:DNA Mutational Analysis; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism*; D009154:Mutation; D046888:Tissue Array Analysis; D055815:Young Adult; D018631:ras Proteins / Q000235:genetics*
chemical_list: D009077:Mucins; D066246:ErbB Receptors; D018631:ras Proteins