Phase II Lung Metcore - Preoperative Metformin for Lung Cancer

Inclusion Criteria:

* Have biopsy-proven non-small cell lung carcinoma (NSCLC) of any histological variant except for neuroendocrine tumors. Patients must not have mixed NSCLC and small cell lung cancer (SCLC).
* Be of clinical stage I to IIIA (according to the 7th lung cancer TNM classification and staging system) by radiologic and/or pathologic criteria where appropriate (e.g. mediastinoscopic staging). Baseline CT-chest scan must be within 4 weeks of study entry.
* Be deemed appropriate candidates for surgical resection by the treating surgeon and assessing team.
* Be aged - 18 years or more.
* Have ECOG performance status - 2.
* Have organ and marrow function as defined below for safe lung biopsy and administration of metformin:

  * Platelets -100 000
  * Total bilirubin -1.5 X institutional upper limit of normal
  * AST/ALT -2 X institutional upper limit of normal
  * Creatinine clearance -60 mL/min/1.73 m2
* Have the ability to understand and the willingness to sign a written informed consent document.
* Not require emergency surgery within 14 days of staging investigations.
* Not have received anticancer treatment with chemotherapy, radiotherapy or Epidermal - - Growth Factor Receptor (EGFR) inhibitor therapy for the current lung cancer.
* Not have a concomitant active malignancy or be receiving any other investigational or anticancer agents while on the study, to avoid the influence of alternative anti-cancer therapy. Otherwise, those with a past history of cancer are eligible.

Exclusion Criteria:

* Not have a past history of an allergic reaction to metformin.
* Not have a past history of diabetes mellitus or fasting glucose ≥ 7.0 mmol/L.
* Not have a past history of lactic acidosis or metabolic acidosis.
* Not have consumption of ≥ 3 alcoholic beverages per day (average).
* Not have had regular use of agents that may influence insulin sensitivity/levels within 4 weeks of study entry.
* Not have uncontrolled intercurrent illness (es) including but not limited to: ongoing or active:

  * Infection,
  * Symptomatic congestive
  * Cardiac failure or evidence of cardiac dysfunction,
  * Unstable angina pectoris,
  * Cardiac arrhythmia,
  * Active peptic ulcer disease or gastrointestinal conditions (e.g. Inflammatory bowel disease) or
  * Psychiatric illness/social situations that would limit compliance with study requirements.
* Not be on a loop diuretic due to their potential to cause renal impairment and predispose to lactic acidosis.
* Not have contrast-enhanced imaging (except when clinically indicated) while on the study. Iodinated contrast agents can cause renal failure, leading to metformin accumulation and lactic acidosis.
* Women should not be pregnant or become pregnant during study.