Colorectal cancer survival following adjuvant chemotherapy with weekly i.v. fluorouracil 425 mg/m2 and folinic acid 50mg
e15089 Background: Adjuvant chemotherapy for colorectal cancer (CRC) using fluorouracil (5FU) and folinic acid (FA) has been proven effective and the QUASAR trial showed that a weekly administration schedule was as effective as, and less toxic than, the same daily doses delivered over 5 days every 4 weeks (the “Mayo regimen”). However the 5FU dose used (370 mg/m2) was lower than in some trials and a higher 5FU dose was considered desirable if tolerated. We therefore implemented a weekly regimen using 5FU 425 mg/m2 and DL-folinic acid 50mg in 2001 and retrospectively evaluated its efficacy and tolerability. Methods: Patients with non-metastatic CRC at assessment by medical oncologists in this institution between 2001 and 2004 were included in the analysis. Data was gathered on patient characteristics, duration of adjuvant chemotherapy and survival. Actuarial survival was calculated using the Kaplan-Meier method. Results: 417 patients (pts) were seen: 181 females, 236 males; median age 67 yrs (24–89); 291 with colon cancer, 126 with rectal cancer; 1 stage 1; 100 stage 2, 316 stage 3. Median follow-up was 6.2 years. 210 pts with colon cancer received adjuvant weekly 5FU/FA (32 stage 2, 178 stage 3) as did 58 pts with rectal cancer (50 of whom also received concurrent chemoradiation). 75% of pts with colon cancer received all 30 planned doses and 59% of rectal cancer pts received all 20 planned doses. 3 year survival for all pts treated with this regimen was 83.0% and for the subgroups with colon and rectal cancer it was 82.4% and 84.5% respectively. For stage 2 and 3 colon cancer pts treated with this regimen 3 year survival was 87.9% and 76.0% respectively; for stage III rectal cancer pts it was 84.1%. Conclusions: These outcomes compare favorably on indirect comparison with results from the QUASAR trial (which reported 3 year survival of 70.6%) and suggest that using a higher 5FU dose in this regimen is tolerable and may be advantageous. No significant financial relationships to disclose.