585P - Five-year results of the XERT phase II trial: Preoperative radiotherapy, capecitabine and cetuximab for treatment of locally advanced rectal cancer

Date 29 September 2014
Event ESMO 2014
Session Poster Display session
Topics Anti-Cancer Agents & Biologic Therapy
Rectal Cancer
Surgery and/or Radiotherapy of Cancer
Presenter Vaneja Velenik
Citation Annals of Oncology (2014) 25 (suppl_4): iv167-iv209. 10.1093/annonc/mdu333
Authors V. Velenik1, J. Ocvirk2, I. Oblak1, F. Anderluh1
  • 1Radiotherapy, Institute of Oncology, 1000 - Ljubljana/SI
  • 2Medical Oncology, Institute of Oncology Ljubljana, SI-1000 - Ljubljana/SI

Abstract

Aim

Preoperative capecitabine-based chemoradiotherapy (CRT) is widely used treatment for resectable locally advanced rectal cancer (LARC). In order to improve efficacy, we conducted a phase II study in which the epidermal growth factor receptor-targeting monoclonal antibody cetuximab was added to capecitabine-based CRT. The results for five-year survival and an analysis investigating the relationship between survival and patient and disease characteristics, including tumour KRAS mutation status, and surgery type, are presented.

Methods

Patients with resectable LARC received capecitabine (1250 mg/m2 twice daily) for 2 weeks followed by cetuximab at week 3 (400 mg/m2), then cetuximab (250 mg/m2/week) and capecitabine (825 mg/m2 twice daily) at week 4. Radiotherapy started at week 4 at a 45 Gy dose (25 x 1.8-Gy) five days a week for five weeks. Surgery was conducted six weeks following CRT, with post-operative chemotherapy with capecitabine (1250 mg/m2 twice daily for 14 days every 21 days) six to eight weeks after the operation.

Results

Forty-three patients were enrolled and thirty-seven underwent treatment. Thirty-six patients were evaluable for efficacy. The median follow-up time for all patients was 69.0 months (range 5.0-106.0), the median follow-up time for all alive patients was also 69 months (range 64-106 months). Eight patients died. The five year overall survival, disease free survival, recurrence free survival and local control were 52.7% (95% CI 43.898-72.364), 72.2% (95% CI 51.998-72.162), 74.3 (95% CI 53.859-73.561) and 96.9% (95% CI 74.743-83.136), respectively. There was no significant association between survival and gender, age, tumour location in the rectum, type of surgery, pathological T or N status, tumour regression grade or tumour KRAS mutation status, although sample sizes were small.

Conclusions

Preoperative cetuximab plus capecitabine-based CRT was feasible in patients with resectable LARC and resulted in excellent five-year local control rate.

Disclosure

All authors have declared no conflicts of interest.