Mortality risk for stage I NSCLC with poor histologic grade, tumor size ≥4 cm, and non-upper lobe tumor location: An epidemiologic study of 19,702 patients in the California Cancer Registry from 1989 to 2003

Abstract

7558 Background: Platinum-based adjuvant chemotherapy in randomized trials has failed to provide a survival benefit in stage I non-small-cell lung cancer (NSCLC). Using data from California Cancer Registry (CCR), we explored factors that have detrimental effect on survival in stage I NSCLC to identify a subset of patients at high risk for relapse and subsequent mortality. Methods: 19,702 stage I NSCLC cases in the CCR from 1989 to 2003 were identified and subgrouped into stage IA & IB disease. Patient demographic factors, tumor characteristics and treatment delivered were examined. Kaplan-Meier survival curves were calculated to estimate survival rates. Cox proportional hazards ratios were used to identify independent prognostic factors for survival. Results: Advanced age at diagnosis, male sex, low socioeconomic status (SES), non-surgical treatment & poorly-differentiated histologic grade (stage IA: hazard ratio [HR] = 1.14; 95% confidence interval [CI]: 1.08–1.19 & stage IB: HR = 1.11; 95% CI: 1.07–1.16) were factors identified with increased mortality risk on multivariate analysis. Non-upper lobe tumor location (RML/RLL/LLL) and tumor size ≥ 4 cm (vs < 4 cm; HR = 1.22; 95% CI: 1.15–1.30) were additional factors with increased mortality risk among stage IB patients. Conversely, bronchioloalveolar carcinoma (BAC)(vs adenocarcinoma: stage IA: HR = 0.81; 95% CI: 0.72–0.91 & stage IB: HR = 0.87, 95% CI: 0.77–0.98) & Asian ethnicity (vs Caucasian: stage IA: HR = 0.81, 95% CI: 0.70–0.94 & stage IB: HR = 0.80, 95% CI: 0.72–0.90) were associated with decreased mortality risk in stage I NSCLC. Lobectomy had the lowest HRs for death among all surgical techniques for both stage IA & IB NSCLC in the Cox proportional hazards model. Conclusions: Poorly-differentiated stage IA & IB NSCLC and stage IB NSCLC located in non-upper lobes or tumor size ≥ 4 cm carried an increased mortality risk on adjusted analysis. No significant financial relationships to disclose. [Table: see text]