Prolonged multimodal disease control with trifluridine/tipiracil plus bevacizumab in KRAS-mutant metastatic rectal cancer: a case report

Refractory metastatic colorectal cancer (mCRC) management is further complicated when fluoropyrimidine-based therapy is contraindicated, leaving few systemic options. We present a 57-year-old man with KRAS G13D-mutant, liver-dominant metastatic rectal adenocarcinoma and recurrent fluoropyrimidine-associated coronary vasospasm precluding 5-fluorouracil and capecitabine. After multimodal first-line therapy and regorafenib, trifluridine/tipiracil (TAS-102) plus bevacizumab was initiated and integrated with liver-directed treatments for oligoprogressive disease. This combined strategy achieved approximately 16.6 months of disease control, substantially exceeding the median progression-free survival reported in the SUNLIGHT trial, with manageable hematological toxicity and preserved performance status. This case highlights the value of TAS-102 plus bevacizumab combined with focal liver-directed therapy as a feasible long-term strategy for selected patients with oligoprogressive mCRC when fluoropyrimidines cannot be used.