Oral doxifluridine in elderly patients with metastatic colorectal cancer: a multicenter phase II study.

BACKGROUND: Cancer chemotherapy in elderly patients is an important and under-researched area. Doxifluridine is a fluoropyrimidine derivative and is activated to 5-fluorouracil by uridine phosphorylase, which is more highly expressed in malignant cells. Because of the high bioavailability and low toxicity of oral doxifluridine we conducted this phase II trial to evaluate the feasibility, toxicity and activity of a home therapy with oral doxifluridine in elderly metastatic colorectal cancer patients. PATIENTS AND METHODS: Forty-three elderly metastatic colorectal cancer patients entered the study: their median ECOG performance status was 1 (0-2) and median age 74 years (69-83), the predominant site of metastasis was liver and all but one of the patients had received no previous chemotherapy. Doxifluridine was given orally at the initial daily total dose of 2250 mg for 4 consecutive days every week. The daily dose was reduced to 1500 mg if toxicities greater than grade 2 (WHO) occurred. RESULTS: Forty-two patients are evaluable for toxicity: treatment was well tolerated, with the most common side effect being diarrhea, severe in 7 (17%) patients (6 grade 3 and 1 grade 4). Thirty-six patients are evaluable for response and 2 complete and 3 partial responses have been observed (response rate 14%; 95% confidence limit interval 5%-29%). CONCLUSIONS: This study demonstrates that a home therapy with oral doxifluridine in elderly advanced colorectal cancer patients is feasible, with a relatively low rate of toxicity, and has moderate activity, comparable to that of intravenous 5-fluorouracil. Therefore, this treatment may be considered for the management of advanced colorectal cancer in the elderly.