Clinical and laboratory examinations were carried out within 7 days before enrollment and each cycle of chemotherapy afterward. Tumor measurement was conducted on the basis of computed tomographic scans, within 15 days before enrollment and every 3 cycles afterward, according to Response Evaluation Criteria in Solid Tumors guidelines (version 1.1). Patients were considered response-assessable if they had overt clinical or radiological evidence of early PD within the first three cycles. All treatment-related adverse events (AEs) were categorized according to the National Cancer Institute’s Common Terminology Criteria for Adverse Events version 4.0 (NCI-CTCAE v4.0).