Phase II study of radiochemotherapy with UFT and low-dose oral leucovorin in patients with unresectable rectal cancer

Purpose: To determine the activity and evaluate the toxicity of uracil and tegafur in a 4:1 molar concentration (UFT) plus low-dose leucovorin adminis tered concomitantly with pelvic irradiation in patients with unresectable o r recurrent rectal cancer. Methods and Materials: Thirty-five patients (22 with primary unresectable t umors and 13 with locally recurrent tumors) were enrolled in the trial. Thi rty-five patients were evaluable for toxicity and 32 of these were evaluabl e for clinical response. Patients received 300 mg/m(2)/day UFT and 30 mg/da y leucovorin on days 8-35 concomitantly with pelvic radiotherapy, to a tota l dose of 45 Gy. Results: Eight of the 35 (23%) patients developed Grade 3 diarrhea and were treated with radiotherapy alone after this event. Of the 22 patients with unresectable primary tumors, 17 underwent surgery, and resection was feasib le in 15 cases (88%). Of the 32 patients evaluable for clinical response, 4 (13%) had a complete clinical response (CR) and 22 (69%) a partial respons e (PR). A complete pathologic response was observed in 3 cases (18%) and, a PR in 11 cases (65%). Conclusion: The response rates achieved with this schedule seem comparable to those obtained with 5-FU and radiotherapy. These results warrant further evaluation of this combination in patients with unresectable or locally ad vanced tumors. (C) 1999 Elsevier Science Inc.