There is no benefit from adjuvant chemotherapy with fluoropyrimidine monotherapy after preoperative (chemo)radiotherapy and total mesorectal excision (TME) in patients with rectal cancer, a study published in the journal Annals of Oncology has shown.
For the multicenter, phase III PROCTOR-SCRIPT trial, researchers enrolled 470 patients from 52 hospitals with histologically proven stage II or III rectal adenocarcinoma. Patients were randomly assigned 1:1 to observation or adjuvant chemotherapy after preoperative (chemo)radiotherapy and TME.
Patients who had radiotherapy received 5 x 5 Gy. Patients who had chemoradiotherapy received 25 x 1.8-2 Gy plus fluorouracil-based chemotherapy. Adjuvant chemotherapy consisted of fluorouracil plus leucovorin or eight cycles of capecitabine.
Results showed that after a median follow-up of 5.0 years, the 5-year overall survival was 79.2% in the observation group and 80.4% in the chemotherapy group (HR = 0.93; 95% CI: 0.62 – 1.39; P = 0.73). Researchers found that the HR for disease-free survival was 0.80 (95% CI: 0.60 – 1.07; P = 0.13).
Both groups had a 7.8% 5-year cumulative incidence for locoregional recurrences, and there was no statistical difference between the two groups for 5-year cumulative incidence for distant recurrences.
The trial was closed early due to slow patient accrual.