Treatment of locally advanced primary and locally recurrent colorectal cancer Roger Dozois, Steven Schild, John Pemberton, Tonia Young-Fadok

Combined-modality chemoirradiation is commonly used as a component of treatment in combination with maximum resection for both resectable highrisk and locally advanced or unresectable primary or locally recurrent rectal cancers.1 With locally unresectable primary or locally recurrent colorectal cancers, standard therapy with surgery, external-beam irradiation (EBRT), and concomitant chemotherapy is often unsuccessful. When intraoperative electron irradiation (IOERT) is added to standard treatment, local control and survival appear to be improved when compared with historical controls in separate analyses from the Mayo Clinic and Massachusetts General Hospital (MGH). Similar results are found in IOERT series from Europe and Japan and in intraoperative high-dose-rate brachytherapy (HDR-IORT) series from the USA and Europe.1-11 However, maintenance systemic therapy is also needed as a component of treatment, in view of the high rates of systemic failure.