Adjuvant and neoadjuvant radiotherapy and concurrent radiochemotherapy for rectal cancer

Radical surgery with negative margins remains the most important prognostic factor in the treatment of rectal cancer. Combined modality treatment is the recommended standard adjuvant therapy for patients with locally advanced rectal cancer in the USA and in Germany. During the last decade substantial progress has been made in treatment modalities: surgical management currently includes a broad spectrum of operative procedures ranging from radical operations to innovative sphincter-preserving techniques. Specialized groups have reported excellent local control rates with total mesorectal excision (TME) alone. New and improved radiation techniques (conformal radiotherapy, intraoperative radiotherapy) and innovative schedules (protracted intravenous infusion, chronomodulated infusion) and combinations (oxaliplatin, irinotecan) of chemotherapy may have the potential to further increase the therapeutic benefit of adjuvant treatment. Moreover, the basic issue of timing of radio-(chemo-)therapy - preoperative versus postoperative - within a multimodality regimen is currently being addressed in prospective trials. Evidently, the current monolithic approaches, established by studies conducted more than a decade ago, to apply either the same schedule of postoperative radiochemotherapy to all patients with stage II/III rectal cancer or to give preoperative intensive short-course radiation according to the Swedish concept for all patients with resectable rectal cancer irrespective of tumor stage and treatment goal (e.g. sphincter preservation), need to be questioned. This review will discuss different irradiation settings in more recent and ongoing studies of perioperative radiotherapy for rectal cancer and will focus on the issue which patient should receive radiotherapy at all, and if so, how and when?