A clinical case of a 61-year-old female diagnosed with stage IV right colon adenocarcinoma (unresectable liver and multiple lymph node metastases at the time of diagnosis), Kirsten rat sarcoma viral oncogene homolog (KRAS), neuroblastoma rat sarcoma viral oncogene homolog (NRAS) and v-raf murine sarcoma viral oncogene homolog B (BRAF) wild-type, proficient mismatch repair (pMMR), in whom a complete response to the third-line of systemic treatment with trifluridine/tipiracil (TAS-102) was obtained. The complete response has been maintained for more than 2 years after its suspension.