Prognostic Factors in Non-Small Cell Lung Cancer (NSCLC)

Background: Non-small cell lung cancer (NSCLC) is the cancer disease with the highest mortality globally. About 75% of NSCLC patients are diagnosed in an advanced stage where surgical treatment is not possible. For patients with locally advanced disease without distant metastases, the treatment of choice is curatively intended radiotherapy. However, this treatment has considerable side effects and many patients relapse. To individualize the treatment strategy for these patients, it is essential to have as much prognostic information as possible. The aim of this thesis was to investigate the prognostic significance of histology and pre-treatment hematopoietic blood parameters. Material and Methods: Data were collected retrospectively for NSCLC patients treated between 1990 and 2000 with curatively intended radiotherapy. The data were obtained by manually searching patient records from all radiation oncology departments in Sweden. The prognostic significance of histology, and pre-treatment levels of hemoglobin (Hgb), white blood cells (WBC) and platelets (Plt) were analyzed in relation to overall survival using univariate and multivariate statistical methods. These prognostic factors were further analyzed in a chemoradiation patient cohort and in a cohort of patients with recurrent NSCLC treated with palliative docetaxel, or the insulin-like growth factor 1 receptor (IGF-1R) modulator AXL1717. Results: In the cohort of NSCLC patients treated between 1990 and 2000, squamous cell carcinoma (SCC) histology and pre-treatment anemia (Hgb <110 g/L), leukocytosis (WBC > 9.0 x109/L), and thrombocytosis (Plt >350 x109/L) were independent prognostic factors for shorter overall survival. However, in the chemoradiation cohort only thrombocytosis retained independent prognostic significance in a multivariate analysis. In the cohort of patients with recurrent disease treated with palliative systemic therapy, only leukocytosis was significantly associated with worse survival. Conclusions: Routine pre-treatment hematopoietic blood parameters—together with other prognostic factors such as disease stage and performance status—can provide decision-making support when individualizing treatment of NSCLC. The prognostic role of histology is unclear and further research is warranted to determine its significance.