Rectal cancer has been one of the leading cancers in Taiwan and other countries in the world. Preoperative neoadjuvant concurrent chemoradiotherapy (CCRT) is the well accepted and widely used modality for locally advanced rectal cancer, to improve the local control, reduce the treatment related toxicity, and to increase the anal preservation rate. Intensity modulated radiation therapy (IMRT), the most common advanced technique in recent 10 years, has been proven effective in dose escalation, treatment target conformity, and normal tissue sparing. The ongoing trials on rectal cancer increasingly adopt IMRT as the treatment technique. Bevacizumab (BV), the developed drug targeting on vascular endothelial growth factor, has been proven for its effective use in metastatic colorectal cancer. Besides, BV has showed its good radiosensitizing effects in the evolving neoadjuvant CCRT trials using traditional big-field pelvis radiotherapy on rectal cancer, the ongoing brain tumor trials, and the basic researches. Neoadjuvant CCRT using the combination of IMRT and BV may have the dual advantages of reduced treatment toxicity by technique and increased pathological response by radiosensitization for the possible improved outcomes. In this phase I trial neoadjuvant CCRT with combined IMRT with three escalated dose levels (45 Gy, 50 Gy, and 55 Gy in 25 fractions) and BV-fluorouracil/ leucovorin/oxaliplatin (FOLFOX) regimens is planned for 15 locally advanced rectal cancer patients. The primary goal is to define the maximally tolerated dose of radiotherapy and the treatment related acute toxicity, and demonstrate that preoperative highly conformal IMRT and concurrent BV-chemotherapy will lead to acceptable acute gastrointestinal morbidity. The secondary goal is to demonstrate that this treatment modality will elicit a comparable or improved rate of T stage downstaging and complete response pathologically.
In this phase I trial neoadjuvant CCRT combining IMRT with three escalated dose levels (45 Gy, 50 Gy, and 55 Gy in 25 fractions) and BV-fluorouracil/ leucovorin/oxaliplatin (FOLFOX) regimens is planned for 15 locally advanced rectal cancer patients. The primary goal is to define the maximally tolerated dose of radiotherapy and the treatment related acute toxicity, and to demonstrate that preoperative highly conformal IMRT and concurrent BV-chemotherapy will lead to acceptable acute gastrointestinal morbidity. The secondary goal is to demonstrate that this treatment modality will elicit a comparable or improved rate of T stage downstaging and complete response pathologically.