Neoadjuvant chemoradiation therapy with double cytotoxic agents is the standard treatment for the patients with locally advanced rectal cancer. Conventional treatment reduced the local recurrence but did not prolong the long-term survival. Furthermore, the patients with pathological complete response (pCR) did not benefit from double cytotoxic chemotherapy. Therefore, we chose triple cytotoxic agents FOLFOXIRI as the neoadjuvant chemotherapy. We will evaluate the efficacy and safety of totally neoadjuvant FOLFOXIRI chemotherapy (irinotecan, oxaliplatin and fluorouracil) followed by short-course radiation and XELOX chemotherapy in the patients with locally advanced rectal cancer to achieve more pCR and longer survival.~In this prospective study, 30 patients with locally advanced rectal cancer will be recruited. Firstly, 4 cycles of neoadjuvant FOLFOXIRI chemotherapy were administered. Subsequently, a short-course radiation therapy (5Gy*5) will be performed. After that, 4 cycles of XELOX chemotherapy will be administered followed by TME surgery. PET-CT examination will be performed before and after the 4 cycles of neoadjuvant FOLFOXIRI chemotherapy to assess the SUVmax changes. In addition, the dynamic changes of ctDNA in peripheral blood will be monitored at the PET-CT examination. In the course of treatment, safety evaluation will be carried out according to the standard of adverse reaction classification (CTCAE) 4.0.
To evaluate the efficacy and safety of totally neoadjuvant FOLFOXIRI chemotherapy (irinotecan, oxaliplatin and fluorouracil) followed by short-course radiation therapy and XELOX chemotherapy in the patients with locally advanced rectal cancer.