In palliative chemotherapy, a focus on palliative treatment is recommended in cases that are unresponsive to multiple drugs. Careful judgment is needed, however, because when treatment is inadequate, cases that are considered to be unresponsive may include some in which chemotherapy would be effective. We treated a patient with metastatic colon cancer who was judged to be unresponsive to multiple drugs at another hospital, yet repetition of standard therapy proved effective. We report this case as an instructive example of the importance of maintaining dose intensity. The patient was a 60-year-old man. Lung metastasis appeared after he had undergone proctectomy and received adjuvant chemotherapy by his previous doctor. Low-dose intensity IFL therapy, FOLFOX4 therapy (once a month), and FOLFIRI therapy (once only) had been performed, but the patient's condition worsened and he was referred to our hospital. This case could not be considered unresponsive to multiple drugs because the treatment had been insufficient, and so we restarted FOLFIRI treatment with the international standard dose and obtained control of the disease. Treatment was then continued, and the patient died 2 years and 11 months after he was first examined at our hospital. Simple palliative treatment alone should not be given unthinkingly when patients are referred for outpatient palliative care. Full consideration of the dosing and schedule is needed.