title: Imaging Characteristics in ALK Fusion-Positive Lung Adenocarcinomas by Using HRCT.
abstract: OBJECTIVE
  We aimed to identify high-resolution computed tomography (HRCT) features useful to distinguish the anaplastic lymphoma kinase gene (ALK) fusion-positive and negative lung adenocarcinomas.
  
  
  METHODS
  We included 236 surgically resected adenocarcinoma lesions, which included 27 consecutive ALK fusion-positive (AP) lesions, 115 epidermal growth factor receptor mutation-positive lesions, and 94 double-negative lesions. HRCT parameters including size, air bronchograms, pleural indentation, spiculation, and tumor disappearance rate (TDR) were compared. In addition, prevalence of small lesions (≤20 mm) and solid lesions (TDR ≤20%) were compared.
  
  
  RESULTS
  AP lesions were significantly smaller and had lower TDR (%) than ALK fusion-negative (AN) lesions (tumor diameter: 20.7 mm ± 14.1 mm vs. 27.4 mm ± 13.8 mm, respectively, p <0.01; TDR: 22.8% ± 24.8% vs. 44.8% ± 33.2%, respectively, p <0.01). All AP lesions >20 mm (n = 7, 25.9%) showed a solid pattern. Among all small lesions, AP lesions had lower TDR and more frequent spiculation than AN lesions (p <0.01). Among solid lesions, AP lesions were smaller than AN lesions (p = 0.01).
  
  
  CONCLUSIONS
  AP lung lesions were significantly smaller and had a lower TDR than AN lesions. Spiculation was more frequent in small lesions. Non-solid >20 mm lesions may be ALK fusion-negative.
authors.affiliation: Department of Thoracic Surgical Oncology, Thoracic Center, The Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Nakada
authors.forename: Sakae
authors.initials: S
authors.lastname: Okumura
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kuroda
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Uehara
authors.forename: Mingyon
authors.initials: M
authors.lastname: Mun
authors.forename: Kengo
authors.initials: K
authors.lastname: Takeuchi
authors.forename: Ken
authors.initials: K
authors.lastname: Nakagawa
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077548:Anaplastic Lymphoma Kinase; D014408:Biomarkers, Tumor / Q000235:genetics*; D066246:ErbB Receptors / Q000235:genetics; D005260:Female; D050939:Gene Fusion; D020022:Genetic Predisposition to Disease; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D009154:Mutation; D010641:Phenotype; D011237:Predictive Value of Tests; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D012189:Retrospective Studies; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; C512478:EGFR protein, human; D066246:ErbB Receptors; D020794:Receptor Protein-Tyrosine Kinases