Aiko Tomiuchi, Michio Kimura, Yoshiaki Ikeda, Eiseki Usami
FTD/TPI monotherapy and FTD/TPI + BV had similar RDI but different toxicity profiles. RDI ≥ 80% did not independently predict OS. In older patients with mCRC, treatment selection, tolerability, and patient-specific factors may be more important than strict dose intensity. These findings suggest that individualized treatment strategies may be important, although further prospective studies are warranted.
PURPOSE: Evidence regarding treatment intensity, tolerability, and outcomes of using trifluridine/tipiracil (FTD/TPI) with or without bevacizumab (BV) in older patients with metastatic colorectal cancer (mCRC) is limited. We compared relative dose intensity (RDI), toxicity, and survival between FTD/TPI monotherapy and FTD/TPI plus BV, and examined the relationship between RDI and overall survival (OS) in older patients.
METHODS: In this single-center retrospective study, patients aged ≥ 75 years with unresectable or recurrent mCRC who received FTD/TPI monotherapy or FTD/TPI plus BV were included. The primary endpoint was RDI; secondary endpoints included treatment exposure, adverse events, achieving RDI ≥ 80%, and OS. Landmark analysis at two treatment cycles and multivariable Cox regression were used to assess the independent effect of the RDI on OS.
RESULTS: Forty-nine patients were included. Median FTD/TPI RDI was 72.9% in the monotherapy group and 74.8% in the combination therapy group, with no significant difference in the proportion achieving an RDI ≥ 80%. Grade ≥ 3 neutropenia occurred in 60.5% of patients in the monotherapy group and 81.8% of patients in the combination therapy group. Hypertension and proteinuria were more frequent in the combination therapy group. Median OS was longer in the combination therapy group (18.3 vs. 8.3 months). RDI ≥ 80% was not associated with OS in landmark or Cox regression analyses. Age and baseline hemoglobin levels were independent prognostic factors.
CONCLUSIONS: FTD/TPI monotherapy and FTD/TPI + BV had similar RDI but different toxicity profiles. RDI ≥ 80% did not independently predict OS. In older patients with mCRC, treatment selection, tolerability, and patient-specific factors may be more important than strict dose intensity. These findings suggest that individualized treatment strategies may be important, although further prospective studies are warranted.