Postoperative radiochemotherapy in rectal cancer comparison of two combination schemes: alternating versus concomitant.

Aims And Background: To compare the results on disease control and toxicity of two different schedules of adjuvant combined treatment in advanced rectal cancer.

Methods: From January 1995 to September 1998, 127 patients with stage B2-C rectal cancer were treated with postoperative chemotherapy and radiotherapy with two different schemes: three cycles of 5-fluorouracil and leucovorin followed by pelvic radiotherapy and three weeks after radiation therapy was completed, another three cycles of chemotherapy were administered (alternating arm), or two cycles of 5-fluorouracil and leucovorin followed by concurrent radiochemotherapy and three weeks after ending another two cycles of 5-fluorouracil and leucovorin were administered (concomitant arm).

Results: Grade 3 acute toxicity was more frequent in the concomitant schedule group (33% vs 13%, P = 0.