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Preoperative chemoradiation therapy
Source: Rectal Cancer Treatment (PDQ®)–Health Professional Version, National Cancer Institute.
Source updated: February 12, 2025 · Captured 2026-09-09.
Selected source text with whitespace normalised. This Triangle page is not an NCI PDQ summary. Independent clinical review is pending.
Context: Treatment Option Overview for Rectal Cancer / Chemoradiation Therapy
Neoadjuvant therapy for rectal cancer, using preoperative chemoradiation therapy, is the preferred treatment option for patients with stages II and III disease. However, postoperative chemoradiation therapy for patients with stage II or III rectal cancer remains an acceptable option.[16][Level of evidence A1] Total neoadjuvant therapy (chemotherapy followed by [chemo]radiation or [chemo]radiation followed by chemotherapy) is also an option.
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Preoperative chemoradiation therapy has become the standard of care for patients with clinically staged T3–T4 or node-positive disease (stages II/III), based on the results of several studies:
German Rectal Cancer Study Group trial.[17]
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National Surgical Adjuvant Breast and Bowel Project R-03 trial NSABP R-03 (NCT00410579).[18][Level of evidence A1] For more information, see the Treatment of Stages II and III Rectal Cancer section.
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Multiple phase II and III studies examined the benefits of preoperative chemoradiation therapy, which include:[16]
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Tumor regression and downstaging of the tumor.
Improved tumor resectability.
Higher rate of local control.
Improved toxicity profile of chemoradiation therapy.
Higher rate of sphincter preservation.
Complete pathological response rates of 10% to 25% may be achieved with preoperative chemoradiation therapy.[19-26] However, preoperative radiation therapy is associated with increased complications compared with surgery alone. Some patients with cancers at a lower risk of local recurrence might be adequately treated with surgery and adjuvant chemotherapy.[27-30] For more information about these studies, see the Preoperative chemoradiation therapy section in the Treatment of Stages II and III Rectal Cancer section.
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Studies cited in this source section
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Preserved source evidence · Independent clinical review pending · Not medical advice