Impact of Bevacizumab Versus Docetaxel/Erlotinib on Tumor Metrics in Patients With Previously Untreated Advanced Non Small Cell Lung Cancer: A Study by the Hellenic Co-operative Oncology Group

In 2008, the Hellenic Co-operative Oncology group (HeCOG) initiated a randomized phase II study to determine the comparative efficacy of intermittent docetaxel/erlotinib chemotherapy, with erlotinib given for twelve consecutive days either before (group A) or after (group B) docetaxel, in chemotherapy-naive patients with advanced non small cell lung cancer. Docetaxel chemotherapy was considered one of the valid non-platinum containing therapeutic options at that time and today represents one of the approved second-line treatment options after failure of first-line platinum based chemotherapy. The trial was terminated early due to slow accrual after enrollment of 51 patients and was published in 2014, showing no clinically meaningful difference between the two treatment arms.

Based on the aforementioned trial population,a parallel radiological study was conducted, evaluating sequential tumor metrics on computed tomography performed at baseline and after each cycle of treatment in patients receiving either bevacizumab or docetaxel/erlotinib. Given the differential mechanism of action of these agents, it was hypothesized that the different parameters of radiological tumor response evaluation, namely the maximum diameter, tumor volume and tumor density, would respond differently for each therapeutic category (a chemotherapeutic agent, a molecular agent and and an anti-angiogenic agent). For bevacizumab, in particular, it was hypothesized that its unique mechanism of action, inducing central tumor necrosis and subsequent shrinkage, would lead to completely different tumor metrics as compared to the other two agents. Herein the final results of this analysis are presented, showing the comparison of the three agents in terms of tumor response metrics, as evaluated in CT scans performed at baseline and after each cycle of treatment