Early clinical results from chemoradiation with 5-fluorouracil and oxaliplatin for locally advanced rectal cancer.

PURPOSE

Preoperative chemoradiation with 5-fluorouracil (5-FU) has improved local control and resectability in patients with locally advanced rectal adenocarcinoma. The possible benefit of adding oxaliplatin is being investigated. We present background on the use of oxaliplatin as well as institutional experience assessing treatment tolerability and early outcome data.

PATIENTS AND METHODS

From August 2001 to August 2006, 15 patients were treated with concurrent 5-FU, oxaliplatin, and radiation. Each had locally advanced rectal carcinoma with staging as follows: T3 (10 patients), T4 (5 patients), N1 (3 patients), and M1 (1 patient). Three patients were treated for local recurrence; 2 had received previous radiation therapy. All patients received continuous-infusion 5-FU at 225 mg/m2 per day. The oxaliplatin dose was 70 mg/m2 in 1 patient and 85 mg/m2 in the others, administered every other week x 3 weeks starting on day 1 of radiation. Resection followed completion of radiation by 6 weeks.

RESULTS

The treatment was tolerable, with the most frequent hematologic toxicity being grade 1/2 anemia. Twelve patients were evaluable, with 11 treated preoperatively. All were able to undergo resection with negative margins, with T stage at resection as follows: T4 (2 patients, 1 with 5% viable tumor), T3 (4 patients), T2 (1 patient), T1 (2 patients); there were pathologic complete responses in 4 patients. At resection, 2 patients had N2 disease; 1 of these was also found to have a peritoneal metastasis. Two patients with clinical N1 disease initially were N0 at resection. With median follow-up of 13 months (range, 4-36 months), 9 patients have clinically no evidence of disease. There have been no local recurrences and 1 death from disease.

CONCLUSION

We present tolerability and early clinical efficacy data for patients treated with concurrent 5-FU and oxaliplatin chemoradiation. The oxaliplatin-based regimen was tolerable. All patients were able to undergo resection with negative margins, with encouraging downstaging, local control, and survival.