Elevated serum granulocyte-macrophage colony-stimulating factor levels during radiotherapy predict favorable outcomes in lung and esophageal cancer

// Guodong Deng 1, * , Pingping Hu 1, * , Jingxin Zhang 2 , Qiqi Liu 1 , Ning Liang 1 , Jian Xie 1 , Lili Qiao 3 , Hui Luo 4 , Deguo Xu 1 , Fengjun Liu 1 , Xinshuang Yu 1 , Zhen liu 1 , Yajuan Lv 1 , Jiandong Zhang 1 1 Department of Radiation Oncology, Qianfoshan Hospital, Shandong University, Jinan 250014, PR China 2 Division of Oncology, Department of Graduate, Weifang Medical College, Weifang 261053, PR China 3 Department of Oncology, The Fifth Peoples’ Hospital of Jinan, Jinan 250022, PR China 4 Department of Radiation Oncology, Henan Cancer Hospital Affiliated to Zhengzhou University, Zhengzhou University, Zhengzhou 450001, Henan, China * These authors have contributed equally to this work Correspondence to: Jiandong Zhang, email: zhangjiand165@126.com Keywords: granulocyte-macrophage colony-stimulating factor, interferon-γ, radiotherapy, cancer prognosis Received: May 23, 2016      Accepted: October 26, 2016      Published: November 08, 2016 ABSTRACT The combination of exogenous granulocyte-macrophage colony-stimulating factor (GM-CSF) with radiotherapy (RT) has been demonstrated to strengthen the antitumor immune response. We hypothesized that the variation of GM-CSF during RT was correlated with cancer prognosis. We measured serum levels of GM-CSF and interferon- γ (IFN- γ ) before and during RT in 126 unresectable lung and esophageal cancer patients and performed survival analyses. Upregulated GM-CSF levels during RT correlated with longer overall survival (OS) and progression-free survival (PFS). On the other hand, no difference in OS or PFS was seen at different IFN- γ levels. However, the “integrated factor”, computed as the combination of high pre-RT IFN- γ levels and upregulated GM-CSF, correlated with prolonged OS and PFS. Multivariate analyses revealed that GM-CSF levels and the integrated factor were both stronger independent prognostic factors than disease stage. These data demonstrate that GM-CSF levels during RT can be used as a prognostic biomarker for lung and esophageal cancer.