Clinicopathological, Immunohistochemical, and Genetic Features of Primary Lung Adenocarcinoma Occurring in the Setting of Usual Interstitial Pneumonia Pattern

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.