Efficacy of neoadjuvant CapeOX/mFOLFOX6 without radiation for patients with baseline resectable mid-low locally advanced rectal cancer.

Abstract

Chemotherapy without radiationtherapy for locally advanced rectal cancer (LARC) has attracted increasing attention, but the optimal schema remains controversial. In this study, we aimedtoassess the efficacy and toxicity of neoadjuvant chemotherapy (nCT) of two regimens for patients with mid-low baseline resectable LARC. A retrospective study was performed in 131 patients withbaseline resectable LARC in a single center between April 2016 and August 2020. All patients received four cycles of neoadjuvant CapeOX or mFOLFOX6beforesurgery. Clinical characteristics, pathological response, and survival status were then assessed. After a 1:1 propensity score matching, 96 patients were enrolled, including 48 receiving CapeOX and 48 receiving mFOLFOX6. The objective regression rates were 50.00% and 58.33%, and the pathological complete response rates were 6.25% and 8.33%, respectively,intheCapeOXandmFOLFOX6groups. Patients who received mFOLFOX6 had a better tumor regression grade (TRG) than those who received CapeOX (P=0.005). Patients in both groups had similar survival outcomes. ThenCT has shown promising tumor response and survival outcomes, which can be atreatment optionfor baseline resectable LARC. For the two regimens, mFOLFOX6 provided better TRG than CapeOX, although no differences were observed in disease-free survival and OS.