Effect of Tabernero's prognostic subgroups or development of neutropenia on survival outcomes of patients with refractory metastatic colorectal cancer (mCRC) treated with trifluridine/tipiracil plus bevacizumab (TASBEV) in real-world practice.

99 Background: TASBEV, compared with TAS-102, was associated with an improvement in progression-free survival (PFS) with tolerable toxicity in a randomized, open-label phase 2 trial. However, the subgroups of patients who may benefit from long-term TASBEV treatment are unknown. Methods: We conducted a retrospective, observational study of patients (pts) with mCRC refractory or intolerant to standard therapies treated with TAS-102 30-35 mg/m2 twice daily on days 1–5 and 8–12 every 28 days plus BEV 5 mg/kg on days 1 and 15 at University Hospital a Coruña (Spain). Results: We recorded 47 pts treated between July 2019 to June 2022. Median age was 65 years (range 41 – 82 years), 78.7% ECOG PS0-1, 51.1% RASmt, 78.7% of pts had liver and 23.4%, peritoneal metastases; 29.8% time since diagnosis of 1st metastases <18 months and 57.4% poor prognostic Tabernero Subgroup. Previous treatment included 94.3% previous antiVEGF treatment and 74.5% received TAS-102 BEV as 3rd line of treatment. Median of cycles received was 4 (range 1-15 cycles). ORR and DCR were 2.4% and 48.8%, respectively. With a median follow up of 15.7 months, median PFS was 4.3 months (95% CI, 3.4-5.1 months) and median OS was 9.8 months (95% CI, 7.3-12.3 months). Univariate analysis of prognostic factors for progression-free and overall survival are listed in the table. Conclusions: In our series identified that Tabernero's prognostic subgroups or the development of grade 3-4 neutropenia during treatment, among others; identify patients who may benefit from long-term TASBEV treatment. [Table: see text]