Neoadjuvant treatment for unresectable rectal cancer: an interim analysis of a multicentre randomized study

To present an interim analysis of the trial comparing two neoadjuvant therapies for unresectable rectal cancer.

Patients with fixed cT3 or cT4 or locally recurrent rectal cancer without distant metastases were randomized to either 5 × 5 Gy and 3 courses of FOLFOX4 (schedule I) or 50.4 Gy delivered in 28 fractions given simultaneously with 5-Fu, leucovorin and oxaliplatin (schedule II). Surgery in both groups was performed 12 weeks after the beginning of radiation and 6 weeks after neoadjuvant treatment.

49 patients were treated according to schedule I and 48 according to schedule II. Grade III+ acute toxicity was observed in 26% of patients in group I and in 25% in group II. There were two toxic deaths, both in group II. The microscopically radical resection (primary endpoint) rate was 73% in group I and 71% in group II. Overall and severe postoperative complications were recorded in 27% and 9% of patients vs. 16% and 7%, respectively. Pathological complete response was observed in 21% of the patients in group I and in 9% in group II.

The interim analysis revealed no major differences in acute toxicity and local efficacy between the two evaluated strategies.