SESSION TYPE: Lung Cancer III
PRESENTED ON: Tuesday, October 23, 2012 at 02:45 PM - 04:15 PM
PURPOSE: Data suggest that diabetes influences survival of patients with colorectal, lung and breast cancer. The anti-cancer effect of metformin, a common oral anti-hyperglycemic drug, further confounds this association. We sought to study the influence of diabetes and metformin on the survival of patients undergoing resection of early non-small cell lung cancer (NSCLC).
METHODS: The Tumor Registry of our NCI Designated Comprehensive Cancer Center was queried for pathologic stage I NSCLC patients undergoing anatomic resection (lobectomy or greater) from 2002-2011. Billing data were used to identify diabetics and pharmacy records were used to identify anti-diabetic medications self-reported during physician and nurse interviews. Univariate analyses examined the association of diabetes and the usage of metformin with overall survival (OS) after resection. Multivariate analyses examined these associations controlling for age, gender, histology (squamous cell cancer, adenocarcinoma and others), stage (IA and IB) and smoking (current, former and never smokers).
RESULTS: Of 3393 consecutive NSCLC cases examined over this time period, 638 patients had pathologic stage 1 disease. Excluding patients with neoadjuvant therapy, more than one lung cancer, or with resection less than lobectomy yielded 409 eligible patients of which 91.7% of the patients were white, 57.9% were female, 9% were never smokers, 63.3% were pathologic stage IA, 59.7% had adenocarcinoma, and 8% underwent a pneumonectomy. In the eligible cohort, 71 (17.4%) were diabetics and 41 (10.0%) used metformin. In univariate analysis, there was no association between a diagnosis of diabetes and OS (P=0.75); however, metformin use was strongly associated with improved OS (median survival not reached vs. 60 months; P=0.02). When controlled for age, gender, pathologic stage (IA vs. IB), histology and smoking status, metformin use remained an important predictor of good survival (HR=2.65; P=0.01).
CONCLUSIONS: Metformin use rather than diabetes improves long term outcome of patients with Stage I lung cancer.
CLINICAL IMPLICATIONS: In concert with in-vitro data supporting anti-cancer effects of metformin, this FDA approved drug deserves consideration as an adjuvant therapy for early lung cancer.
DISCLOSURE: The following authors have nothing to disclose: Samjot Dhillon, Alison Meagher, Todd Demmy, Graham Warren, Sai Yendamuri
No Product/Research Disclosure InformationRoswell Park Cancer Institute, Buffalo, NY