Lay Summary: Chemoradiation is the preferred approach to upfront treatment of rectal cancer whenever possible.
“Chemoradiation” is combined simultaneous administration of chemotherapy and radiation treatments. Chemoradiation is an important tool in the treatment of rectal cancer. The term “neoadjuvant” refers to the concept of administering chemotherapy and/or radiation therapy prior to surgery. The purpose of neoadjuvant chemoradiation therapy is twofold: to shrink a tumor to facilitate subsequent surgical removal and to improve a patient’s chance for cure. It follows that even thel cancer of a size and location that permit resection first should subsequently have adjuvant chemoradiation therapy to improve their chance for a cure.
A typical chemoradiation regimen might consist of daily (Monday through Friday) radiation treatments concurrent with daily (Monday through Friday) continuous infusion 5-fluorouracil (5-FU). This chemoradiation is typically given over a period of five to six weeks. Chemotherapy is given with radiation therapy in order to sensitize tumor cells to radiation, and because the combination has been shown to be more effective than the use of either modality alone. Continuous infusion rather than bolus (a daily 5-10 minute infusion) chemotherapy is preferred as it has resulted in improved survival rates in one study. This regimen may be given pre- or postoperatively for locally advanced tumors (T3/T4 or N1/N2) where it has been shown to reduce the chance of tumor recurrence and improve the chance for cure. Xeloda is also an acceptable alternative with radiation. Postoperatively NCCN recommends Folfox, Xeloda or 5FU/ Lekovorin.
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nccn.org, colorectal 2018