Cancer is a known risk factor for the development of venous thromboembolism (VTE) and in particular, adenocarcinoma of the lung is known to be associated with a higher risk of thromboembolic event. EGFR activating mutations are more frequently found in this histological subtype than in other lung cancers. We report three cases of VTE in patients with adenocarcinoma of the lung and EGFR activating mutation. Our reported case series is atypical because the VTE event occurred early in the adenocarcinoma history: either leading to the diagnosis of cancer, or appearing very early in the management of the neoplasm.