The prognostic factors for refractory metastatic colorectal cancer treated with trifluridine–tipiracil.

e15542 Background: Treatment for refractory metastatic colorectal cancer is still a challenge. In the previous studies, the overall survival would increase by 6-8 months with trifluridine–tipiracil (FTD–TPI) or regorafenib. The further trial revealed that combination usage with FTD–TPI and Bevacizumab improved survival to 10.8 months. We tried to analyze the possible factors that would extend potential survival retrospectively. Methods: This was a retrospective study. We collected the patients who had refractory metastatic colorectal cancer, all received prior treatment, including 5-FU, Oxaliplatin, Irinotecan, vascular endothelial growth factor (VEGF), and epidermal growth factor receptor if wild type K-RAS. We analyzed the potential factors that would extend the survival time. Results: There were 80 patients enrolled in this study from Nov. 2019 to Nov. 2024. The demographic is summarized in the table below. The mean overall survival (OS) was 22.4 months, with progression-free survival (PFS) of 10.4 months. Thirty patients (37.5%) received local treatment including metastasectomy, radiotherapy, or ablation. We found that local treatment and prior stage 4 treatment time of more than 12 months were good prognostic factors. Patients had statistically significantly longer PFS of 14.1 months in the local treatment group and PFS of 11.2 months in prior treatment time more than 12 months, respectively. For the OS, the positive factors that extended survival were local treatment, prior stage 4 treatment time of more than 12 months, remaining single metastasis site, and metachronous cases. Conclusions: For refractory metastatic colorectal cancer, aggressive treatment could prolong the survival time. Local treatment for the metastasis site and prior aggressive treatment could provide longer PFS and overall survival. Patient characteristics (n=80) Gender Male : female 48: 32 Age 59.3 ± 11.4 y/o Synchronous: metachronous 51: 29 K-RAS Wild type: mutant K-RAS G12 / G13 / others 33: 47 36/8/3 MSI-S / pMMR 76 (4 missing data) BRAF mutant 1 Combination No Single combined with VEGF Combined VEGF and chemotherapy Combined chemotherapy 5116112 Local treatment 30 Metastasis site Single (liver/lung / distant LN) Multiple / peritonum 5129 Survival factors analysis Overall survival (M) Synchronous/metachronous Metastasis site (single: multiple/peritoneum) Prior stage 4 treatment time> 12 months Local treatment (Y:N) 19.3: 23.7 * 28.6: 13.5* 23.5: 10.9* 26.5: 16.3* Progression-free survival (M) Synchronous/metachronous Metastasis site (single: multiple/peritoneum) Prior stage 4 treatment time> 12 months Local treatment (Y:N) 10.3: 9.612.0: 6.411.2: 3.2* 14.1: 7.0* *statistic significant difference with p<0.05.