Phase I Clinical Study of Every Three Week Irinotecan With Oral Capecitabine Given Twice Daily for Two Weeks Out of Three in Patients With Gastrointestinal and Other Solid Malignancies

OBJECTIVES: I. Determine the maximum tolerated dose and toxic effects of irinotecan and oral capecitabine in patients with gastrointestinal or other solid tumors. II. Characterize the relationship at the recommended phase II dose between thymidine synthase and thymidine phosphorylase expression and tumor response and/or toxic effects in these patients.

OUTLINE: This is a dose escalation study. Patients receive oral capecitabine twice daily every twelve hours for 14 days, and IV irinotecan over 30 minutes once every 3 weeks beginning on day 1. Treatment continues for at least 2 courses in the absence of disease progression or unacceptable toxicity. The dose of capecitabine and irinotecan is escalated in cohorts of 3-6 patients until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which 2 of 6 patients experience dose limiting toxicity.

PROJECTED ACCRUAL: Approximately 25-30 patients will be accrued for this study.