Comparison of Two Chemotherapy Regimens After First-Line Treatment for HER2-Negative Metastatic Gastric Cancer

Aim: Metastatic stage gastric cancer is a disease with a poor prognosis and the likelihood of achieving a cure in these patients is low. Treatment response to subsequent-line treatments is poor. We aimed to investigate the effectiveness of the folinic acid, fluorouracil and irinotecan (FOLFIRI) and paclitaxel+carboplatin regimens, which are used in subsequent lines of therapy in advanced-stage gastric cancer. Materials and methods: This study included 40 patients who have metastatic stage gastric cancer and received FOLFIRI or paclitaxel+carboplatin therapy in subsequent lines of therapy between 2017 and 2022. The data of the patients were analyzed retrospectively. Results: At diagnosis median age was 51 (23-88) years. The tumor was localized in the gastroesophageal junction in eight (20%) patients and in other gastric locations in 32 (80%) patients. At diagnosis, 75% (n=30) of the patients presented with the disease in the metastatic stage, while 25% (n=10) presented with stage II-III disease. Regarding the treatments received in the second and further lines of therapy, 18 (45%) patients received paclitaxel+carboplatin and 22 (55%) patients received a FOLFIRI regimen. Of these treatments, 67.5% (n=27) were given as the second line and 32.5% (n=13) were given as third-line therapy. The objective response rate (ORR) was 45.5% in the FOLFIRI arm compared to 16.7% in the paclitaxel+carboplatin arm (p=0.05). Both treatment arms had a median progression-free survival (PFS) of three months (p=0.82). The median overall survival (OS) time was seven months in the FOLFIRI arm compared to eight months in the paclitaxel+carboplatin arm (p=0.71). Side effects were similar between both treatment arms. Conclusion: This study determined that FOLFIRI and paclitaxel+carboplatin treatments have similar OS, PFS, and side effect profiles in subsequent line treatment of gastric cancer. The FOLFIRI treatment regimen yielded a higher ORR.