Continuous versus intermittent chemotherapy in metastatic colorectal cancer
3582 Background: The current policy concerning the duration of chemotherapy in metastatic colorectal cancer (MCC) varies considerably (Clin Oncol 1997;9:248) while no benefit of continuous versus intermittent 5-FU was found in a published randomized study (Lancet 2003;361:457). Serious cumulative toxicity is not usually a problem with long-term 5-FU/FA, but this is not the case with contemporary triple regimens (FOLFIRI, FOLFOX). We, therefore, performed a randomized study of continuous versus intermittent FOLFIRI as first line chemotherapy in MCC. Methods: Patients with MCC and ECOG 0–2 were given 6 biweekly courses of FOLFIRI (Irinotecan 180mg/m2 + De Gramont). Patients with response or stable disease were randomized to continue with another 6 FOLFIRI (group A) or discontinue until relapse when 6 FOLFIRI were readministered (group B). Time to progression (TTP) was calculated from study entrance until 1st progression for group A, and 2nd progression for group B, and overall survival (OS) from study entrance until death. Results: Fifty eight (M=38, F=20) patients entered into the study. Two (3.4%) withdrew before evaluation, 1 (1.7%) died of stroke, 1 (1.7%) was lost to FU and 15 (26%) progressed before or at the completion of 6 FOLFIRI. Thirty nine (67%) patients (M=25, F=14), median age 69 (38–79) responded (21=54%) or had stable disease (18=46%) and were randomized: 19 (49%) to group A and 20 (51%) to group B. Median TTP was 8 months 95% CI: 5.3–10.7) for group A and 9 (95% CI: 7.8–10) for group B (p=NS). 10/19 (52%) in group A received 2nd line chemotherapy vs 7/20 (35%) in group B (p=NS). With a median follow-up of 13 months, 21 patients are alive (12 in group A and 9 in group B). Median OS was 21 months (95% CI: 15 - 26.7) in group A vs 15 (95% CI: 12.6 - 17.3) in group B (p=NS), and 18 months (95% CI: 15.5 - 21) for all 39 patients. Conclusions: In MCC, when response or stability has been achieved after 6 courses ofFOLFIRI there seemstobe little more benefit from continuing chemotherapy than from retreating patients at relapse No significant financial relationships to disclose.