Clinicopathological and prognostic features of surgically resected pathological stage I lung adenocarcinoma harboring epidermal growth factor receptor and K-ras mutation.
This study aimed to evaluate mutations of the epidermal growth factor receptor (EGFR) and K-ras genes and their clinicopathological and prognostic features in patients with resected pathological stage I adenocarcinoma.



We examined 224 patients with surgically resected lung adenocarcinoma and analyzed the prognostic and predictive value of these mutations in 162 patients with pathological stage I adenocarcinoma.



Mutations of the EGFR and K-ras genes were detected in 100 (44.6%) and 19 (8.5%) of all tumors, and in 81 (50.0%) and 17 (10.5%) of the pathological stage I tumors, respectively. EGFR mutations were significantly associated with female gender, smoking habit (never smoker), and low grade. By contrast, K-ras mutations were significantly associated with male gender, smoking habit (ever smoker), and the presence of mucinous components. No significant differences were observed in recurrence-free or overall survival between the EGFR-mutant, K-ras-mutant, and wild-type groups (five-year recurrence-free survival 77.8% vs. 87.8% vs. 79.5%; five-year overall survival 82.8% vs. 82.4% vs. 79.2%, respectively). Multivariate analysis showed that neither EGFR nor K-ras mutation was an independent prognostic factor.



The present study demonstrated that pathological stage I adenocarcinoma harboring EGFR and K-ras gene mutations have distinct clinicopathological features. The presence of these mutations alone were not prognostic factors in patients with resected pathological stage I adenocarcinoma.
Department of Thoracic Surgery, Sagamihara Kyodo Hospital, Sagamihara, Japan.
Kaoru
K
Kaseda
Department of Thoracic Surgery, Sagamihara Kyodo Hospital, Sagamihara, Japan.
Keisuke
K
Asakura
Department of Pathology, Sagamihara Kyodo Hospital, Sagamihara, Japan.
Akio
A
Kazama
Yuai Clinic, Yokohama, Japan.
Yukihiko
Y
Ozawa
D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D011379:Prognosis; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics*; D012727:Sex Characteristics; D012907:Smoking / Q000009:adverse effects
C117307:KRAS protein, human; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras)

Adenocarcinoma; 
K-ras
; epidermal growth factor receptor