A COX-2 inhibitor combined with chemoradiation of locally advanced rectal cancer: a phase II trial

Background and aim The aim of this study was to investigate the possible effect of a COX-2 inhibitor in addition to chemoradiation of locally advanced rectal cancer. Materials and methods The study included 35 patients with rectal adenocarcinoma. All patients had a tumor localised <= 10 cm from the anal verge and a circumferential margin <= 5 mm on a magnetic resonance scan. The patients were scheduled to receive external radiation with a tumor dose of 60 Gy supplemented with an endorectal boost of 5 Gy. Concurrent with radiation, the patients received uracil-tegafur 300 mg/m(2) daily. Celexocib was scheduled throughout the radiation period in a dose of 400 mg x 2 daily. Results A macular papular rash was seen in 17 (49%) of the patients leading to stop of medication with celecoxib. Thirty-three patients were operated, and all patients responded to treatment. Complete pathological remission was found in 21% of the patients and further 24% had only microscopic residual tumor cells. The results did not suggest any difference according to the accomplishment of the COX-2 medication. Conclusion The addition of a COX-2 inhibitor to chemotherapy-enhanced radiation treatment of rectal cancer was not feasible due to a high incidence of rash in the present study.