Abstract
OBJECTIVE: Many large-sample prospective randomized clinical trials investigating advanced gastric cancer (AGC) have confirmed the survival advantages of first-line, second-line, or third-line chemotherapy compared with their respective control groups. However, due to the ethical concerns of prospective clinical trials, it is impossible to conduct a randomized comparative study of patients who do not receive chemotherapy and those who receive a second-line or above chemotherapy. Few research reports have addressed the relationship between the number of chemotherapy lines and overall survival (OS) in patients with AGC. In the present study, we analyzed the impact of the number of chemotherapy lines on OS in AGC patients using real-world data. PATIENTS AND METHODS: This study collected the medical records of patients with AGC diagnosed at Shandong Cancer Hospital from December 2007 to December 2017. According to the treatment received, AGC patients were divided into groups that did not receive chemotherapy, those who received only 1 line, 2 lines, or 3 lines and above. Kaplan-Meier analysis was used to assess patient survival. RESULTS: A total of 596 AGC patients were included in this study. The following patients were enrolled: 0 lines (did not receive chemotherapy), 77 (12.9%); 1 line, 235 (39.4%) patients; 2 lines, 185 (31.1%) patients; and ≥3 lines 99 (16.6%) patients. OS was significantly correlated with the number of chemotherapy lines (P<0.001), with a median OS from diagnosis of 3.3, 8.6, 15.6, and 21.0 months for patients receiving 0, 1, 2, ≥3 lines of chemotherapy, respectively. CONCLUSION: This study showed that the more chemotherapy lines AGC patients received, the longer the OS. This study not only confirmed the impact of chemotherapy lines on OS but it also supplements the results of prospective clinical trials that cannot be completed due to the ethical implications.