Delivery of mFOLFOX6 after chemoradiation and before total mesorectal excision in patients with locally advanced rectal cancer has the potential to increase the proportion of patients eligible to receive less invasive treatment strategies, a new study published online ahead of print in The Lancet Oncology has shown.
For the phase 2 trial, researchers enrolled 259 patients with stage 2-3 locally advanced rectal cancer. Patients were divided into four groups. All patients received chemoradiation for 5 weeks.
Patients in group 1 underwent total mesorectal excision 6 to 8 weeks following chemoradiation, while patients in groups 2 through 4 received two, four, or six cycles of mFOLFOX6, respectively, after chemoradiation and before surgery.
Results showed that 18% (95% CI: 10, 30), 25% (95% CI: 16, 37), 30% (95% CI: 19, 42), and 38% (95% CI: 27, 51) of patients in groups 1 through 4, respectively, achieved a complete pathological complete response (P=0.0036).
Researchers found that study group was independently associated with pathological complete response (group 4 versus group 1 OR = 3.49; 95% CI: 1.39, 8.75; P=0.011).
In regard to safety, the most common serious adverse events associated with neoadjuvant mFOLFOX6 administration were neutropenia and lymphopenia.
This treatment modality is being further evaluated in phase 3 clinical trials.