Neoadjuvant chemoradiotherapy adherence associated with improved disease-free survival in patients with rectal cancer

Patients with locally advanced rectal cancer who adhered to neoadjuvant chemoradiotherapy had significantly improved disease-free survival (DFS), according to results form a post hoc analysis of a phase 3 randomized clinical trial published in JAMA Oncology.

After a median follow-up of 50 months, patients treated with neoadjuvant fluorouracil-based chemoradiotherapy (nCRT) (n = 625) had a 3-year DFS in the as-treated population of 71.1%. Three-year DFS in patients treated with fluorouracil-based nCRT with the addition of oxaliplatin (n = 607) was 75.8%.

Overall, 67% and 71.5% of patients in the fluorouracil nCRT group the fluorouracil-oxaliplatin nCRT group, respectively, received full doses of preoperative nCRT.

Of the 1126 patients to have curative surgery, 439 started fluorouracil-based adjuvant chemotherapy and 419 started fluorouracil-based adjuvant chemotherapy with oxaliplatin. In the fluorouracil group and the fluorouracil-oxaliplatin group, 57.6% and 32%, respectively, received full doses of adjuvant chemotherapy.

Multivariable analyses showed that adherence to nCRT was associated with 3-year DFS in the fluorouracil group and the fluorouracil-oxaliplatin group, whereas adjuvant chemotherapy was not associated with DFS in the fluorouracil group and the fluorouracil-oxaliplatin group.

Reference

Diefenhardt M, Ludmir EB, Hofheinz R, et al. Association of Treatment Adherence With Oncologic Outcomes for Patients With Rectal Cancer: A Post Hoc Analysis of the CAO/ARO/AIO-04 Phase 3 Randomized Clinical Trial. JAMA Oncol. Published online July 09, 2020. doi:10.1001/jamaoncol.2020.2394