title: Clinicopathological, Immunohistochemical, and Genetic Features of Primary Lung Adenocarcinoma Occurring in the Setting of Usual Interstitial Pneumonia Pattern.
abstract: An association between usual interstitial pneumonia (UIP) and carcinogenesis has been well established. However, few detailed analyses have investigated the clinicopathological, immunohistochemical, and genetic features of patients with primary lung adenocarcinoma (ADC) with UIP (UIP-ADC).
  
  
  
  We identified 44 patients with ADC in the setting of UIP (the UIP-ADC group) (1.9%) from 2309 patients with primary ADC and compared clinicopathological, immunohistochemical, and genetic features between the UIP-ADC group and patients with ADC without UIP (the non-UIP-ADC group).
  
  
  
  Clinicopathological features of UIP-ADC included an older age at occurrence; male predominance; smoking history; predilection for the lower lobe; large tumor size; high incidence of lymph vessel invasion, pleural invasion, and lymph node metastasis; and poor survival rate. However, the cause of death of patients with UIP-ADC was largely influenced by respiratory complications. Histologically, patients in the UIP-ADC group could be stratified according to invasive mucinous-predominant subtype. Genetically, patients in the UIP-ADC group had lower EGFR and higher KRAS mutation rates compared with patients in the non-UIP-ADC group.
  
  
  
  UIP-ADC was associated with a poor prognosis owing to the high frequency of perioperative complications rather than the malignancy of the tumor itself. There was a high prevalence of the invasive mucinous-predominant subtype in cases of UIP-ADC. UIP-ADC also had a low prevalence of EGFR mutations and a high prevalence of KRAS mutations. These findings suggest that UIP-ADC should be distinct from non-UIP-ADC.
authors: Department of Pathology and Clinical Laboratories, National Cancer Centre Hospital, Tokyo, Japan; Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan; Division of Thoracic Surgery, Keio University School of Medicine, Tokyo, Japan.
authors: Kyohei
authors: K
authors: Masai
authors: Clinical Laboratory Division, Kansai Medical University Hirakata Hospital, Osaka, Japan. Electronic address: tsutakoj@hirakata.kmu.ac.jp.
authors: Koji
authors: K
authors: Tsuta
authors: Department of Pathology and Clinical Laboratories, National Cancer Centre Hospital, Tokyo, Japan.
authors: Noriko
authors: N
authors: Motoi
authors: Department of Pathology and Clinical Laboratories, National Cancer Centre Hospital, Tokyo, Japan.
authors: Kouya
authors: K
authors: Shiraishi
authors: Department of Pathology and Clinical Laboratories, National Cancer Centre Hospital, Tokyo, Japan.
authors: Koh
authors: K
authors: Furuta
authors: Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan.
authors: Shigeki
authors: S
authors: Suzuki
authors: Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan.
authors: Keisuke
authors: K
authors: Asakura
authors: Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan.
authors: Kazuo
authors: K
authors: Nakagawa
authors: Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan.
authors: Hiroyuki
authors: H
authors: Sakurai
authors: Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan.
authors: Shun-Ichi
authors: SI
authors: Watanabe
authors: Department of Pathology and Clinical Laboratories, National Cancer Centre Hospital, Tokyo, Japan.
authors: Nobuyoshi
authors: N
authors: Hiraoka
authors: Division of Thoracic Surgery, Keio University School of Medicine, Tokyo, Japan.
authors: Hisao
authors: H
authors: Asamura
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D017563:Lung Diseases, Interstitial / Q000235:genetics* / Q000473:pathology; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
keywords: Adenocarcinoma; EGFR; IPF; KRAS; Pulmonary fibrosis; UIP