Author of

• 12701

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  P3.12 - Poster Session 3 - NSCLC Early Stage (ID 206)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Medical Oncology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/30/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

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    P3.12-006 - Clinical Significance of Ki67 Expression in Curatively Resected Non-small Cell Lung Cancer (ID 1521)

    09:30 - 09:30  |  Author(s): J. Lee
    • Abstract

    Background
    Ki67 and p53 were suggested to be associated poor survival in stage I-III patients. The aim of this study was to explore the association of Ki67 and p53 expression with prognosis in curatively resected non-small cell lung cancer (NSCLC) patients.

    Methods
    We retrospectively identified patients with stage I-III NSCLC who underwent curative surgery in Gachon University Gil Medical Center from January 2007 to December 2012. Ki67 and p53 expression levels were evaluated by immunohistochemistry. Clinicopathologic features and disease free survival (DFS) were retrospectively estimated.

    Results
    One hundred and eighteen consecutive patients with Ki67 or p53 results were identified. Median Ki-67 labeling index was 30%. P53 expression was positive in 88 (25%) patients. Higher Ki67 expression (>30%) was significantly frequent in male(53.0% vs 13.3% of female, p<0.001) and non-adenocarcinoma(64.3% vs. 20.3% of adenocarcinoma, p<0.001) patients. In univariate analysis, median DFS had a trend toward worse in patients with higher Ki67 (55.9 months vs. not reached in those with lower Ki67 expression, p=0.113) and with positive p53 (55.9 months vs. not reached in those with negative p53 expression, p=0.123). In Cox multivariate analysis, higher Ki-67 expression was an signitifant independent prognostic factor associated with poorer DFS (HR 3.083, 95% CI 1.342-7.084), along with histology and stage. Among 44 stage Ib patients, 14 patients received adjuvant chemotherapy. In stage IB patients with higher Ki67 expression, adjuvant chemotherapy administration had a trend toward higher 3-year DFS rate (100% vs. 72% in patients without adjuvant chemotherapy). In contrast, 3-year DFS rate with adjuvant chemotherapy was 69%, compared with 79% without adjuvant chemotherapy in stage IB patients with lower Ki67 expression. In patients with tumor size≥4cm, there was no differences in DFS according to adjuvant chemotherapy.

    Conclusion
    Higher Ki67 expression was independently associated with shorter DFS in resected NSCLC patients. In stage IB, higher Ki67 seemed to be associated benefit of adjuvant chemotherapy. The value of Ki67 as a predictive biomarker of advantage of adjuvant chemotherapy should be further studied in a prospective larger cohort.