Author of

• 10850

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  P1.12 - Poster Session 1 - NSCLC Early Stage (ID 203)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Medical Oncology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/28/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 10853

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    P1.12-003 - Preoperative neutrophil and lymphocyte counts are independent prognostic factors in completely resected non-small cell lung cancer (ID 1085)

    09:30 - 09:30  |  Author(s): M. Onizuka
    • Abstract

    Background
    The pretreatment ratio of neutrophils to lymphocytes has recently been reported as a prognostic factor in non-small cell lung cancer (NSCLC). However, the mechanism behind this is unclear. Therefore, we separately investigated the influences of neutrophil and lymphocyte counts on prognosis in completely resected NSCLC.

    Methods
    We conducted retrospective analyses of patients diagnosed with NSCLC who underwent surgery involving complete resection at Tsukuba University Hospital between 2000 and 2009. Patients with preoperative treatment, suspicion of granulocyte colony-stimulating factor-producing tumor, and unmeasured differential leukocyte count were excluded. Univariate analysis was performed using the Kaplan-Meier method, and statistical significances were assessed by the log-rank test. The cut-off values of neutrophil and lymphocyte counts were defined as the maximal log-rank statistical values. Then, we divided the patients into two groups according to the optimal cut-off values to investigate the association with clinicopathological factors. Chi-square test was used for categorical variables and t test was used for continuous variables. To assess the independent predictive values, Cox proportional hazards model was used. The result was considered to be significant when the P value was less than 0.05.

    Results
    A total of 328 patients were evaluated. There were 217 men and 111 women. The patients’ age at the time of operation ranged from 29 to 89 years (mean, 67.0 years). The mean follow-up was 41.0 months (range, 1-118 months). Two hundred and ten patients were classified as Stage I, 72 patients as Stage II, and 46 patients as Stage III. The overall 5-year survival rate of all 328 patients was 71.1%. As for the neutrophil count, the maximum log-rank statistical value was 11.456 (P < 0.001) when the cut-off value was 5200 mm[-3]. The overall 5-year survival rates were 74.2% for the low-neutrophil-count group (neutrophil count ≤ 5200 mm[-3]), and 48.8% for the high-neutrophil-count group (neutrophil count > 5200 mm[-3]). As for the lymphocyte count, the maximum log-rank statistical value was 7.275 (P = 0.007) when the cut-off value was 1700 mm[-3]. The overall 5-year survival rates were 65.5% for the low-lymphocyte-count group (lymphocyte count ≤ 1700 mm[-3]) and 75.4% for the high-lymphocyte-count group (lymphocyte count > 1700 mm[-3]). High neutrophil count was significantly associated with tumor size, pleural invasion, sex, smoking index, lactate dehydrogenase, and C-reactive protein. On the other hand, low lymphocyte count was related to tumor size, vascular invasion, and age. Cox proportional hazards model showed that neutrophil count and lymphocyte count were independent prognostic factors. The hazard ratio of neutrophil count was 1.880 (P = 0.022), and that of lymphocyte count was 1.645 (P = 0.036). Other significant factors were tumor size (hazard ratio: 2.418, P = 0.001) and lymphatic invasion (hazard ratio: 1.829, P = 0.035). Pleural invasion, nodal status, and vascular invasion were not significant.

    Conclusion
    Preoperative neutrophil count and lymphocyte count were independent prognostic factors in completely resected NSCLC. High neutrophil count was associated with tumor size and pleural invasion, and low lymphocyte count was associated with tumor size and vascular invasion.