Radiation Therapy for Rectal Cancer

Publication Date: October 19, 2020
Last Updated: March 14, 2022

Recommendations for neoadjuvant RT indications

For patients with rectal cancer, pelvic MRI with a rectal cancer protocol is recommended for preoperative clinical T and N staging. (Moderate-quality evidence, Strong recommendation)
608
For patients with stage II-III rectal cancer, neoadjuvant RT is recommended. (Moderate-quality evidence, Conditional recommendation)
608
For patients with stage II rectal cancer at lower risk of locoregional recurrence, omission of neoadjuvant RT is conditionally recommended after discussion with a multidisciplinary team. (Moderate-quality evidence, Conditional recommendation)
Implementation remark: Lower risk is defined as a cT3a/b N0 tumor that is >10 cm from the anal verge and with mrCRM ≥2 mm and no mrEMVI.
608
For patients with cT1-2N0 rectal cancer who may need an APR, neoadjuvant chemoradiation is conditionally recommended to improve the chance of sphincter preservation. (, Conditional recommendation)
Expert Opinion
608
For patients with rectal cancer where radiation is indicated, RT should be performed preoperatively rather than postoperatively. (High-quality evidence, Strong recommendation)
608

Recommendations for neoadjuvant regimens

For patients with rectal cancer receiving neoadjuvant chemoradiation, conventional fractionation from 5000-5040 cGy in 25-28 fractions with concurrent chemotherapy is recommended. (High-quality evidence, Strong recommendation)
608
For patients with rectal cancer receiving neoadjuvant short-course RT, 2500 cGy in 5 fractions without concurrent chemotherapy is recommended. (High-quality evidence, Strong recommendation)
608
For patients with rectal cancer undergoing neoadjuvant chemoradiation, only concurrent 5-fluorouracil or capecitabine is recommended with RT for radiosensitization. (High-quality evidence, Strong recommendation)
608
For patients with rectal cancer undergoing neoadjuvant therapy, chemotherapy alone (FOLFOX or CAPOX) is conditionally recommended only in the context of a clinical trial or multi-institutional registry. (Low-quality evidence, Conditional recommendation)
608
For patients with rectal cancer undergoing neoadjuvant therapy without tumor factors that portend increased recurrence risk, (1) chemoradiation or (2) short-course RT are recommended. (High-quality evidence, Strong recommendation)
Implementation remark: Risk factors for increased recurrence include cT3 tumors ≤5 cm from the anal verge or mrCRM <2 mm; cT4 tumor or cN2 disease, presence of mrEMVI.
608
For patients with rectal cancer undergoing neoadjuvant therapy without tumor factors that portend increased recurrence risk, addition of multiagent (FOLFOX or CAPOX) chemotherapy (1) before or after chemoradiation or (2) after short-course RT is conditionally recommended. (Low-quality evidence, Conditional recommendation)
Implementation remark: Risk factors for increased recurrence include cT3 tumors ≤5 cm from the anal verge or mrCRM <2 mm; cT4 or cN2 disease, presence of mrEMVI.
608
For patients with rectal cancer undergoing neoadjuvant therapy with tumor factors that portend increased recurrence risk, addition of multiagent (FOLFOX or CAPOX) chemotherapy (1) before or after chemoradiation or (2) after short-course RT is conditionally recommended. (Moderate-quality evidence, Conditional recommendation)
Implementation remark: Risk factors for increased recurrence include cT3 tumors ≤5 cm from the anal verge or mrCRM <2 mm; cT4 or cN2 disease, presence of mrEMVI.
608
For patients with rectal cancer receiving neoadjuvant chemotherapy as a component of a total neoadjuvant therapy strategy, 3-4 months of either FOLFOX or CAPOX (without additional agents, targeted therapy, or immunotherapy) is recommended. (Moderate-quality evidence, Strong recommendation)
608
For patients with rectal cancer undergoing neoadjuvant chemoradiation with no further neoadjuvant chemotherapy planned, an interval of 6-11 weeks from the end of chemoradiation to surgery is recommended.
  • ≥6 weeks
(High-quality evidence, Strong recommendation)
608
  • 6-11 weeks
(Moderate-quality evidence, Strong recommendation)
608
For patients with rectal cancer undergoing neoadjuvant short-course RT with no further neoadjuvant chemotherapy planned, an interval of either ≤3 days or 4-8 weeks from the end of RT to surgery is recommended. (Moderate-quality evidence, Strong recommendation)
Implementation remark: An interval of 4-8 weeks is preferred for patients who may benefit from tumor downstaging before resection.
608

Recommendations for nonoperative or LE approaches

NOM is conditionally recommended after multidisciplinary discussion if a cCR is achieved after neoadjuvant treatment in patients with rectal cancer who:
a. would have a permanent colostomy or inadequate bowel continence after TME AND
b. decline TME AND
c. agree to close follow-up by a multidisciplinary team.
(Moderate-quality evidence, Conditional recommendation)
608
Organ preservation through neoadjuvant chemoradiation followed by LE is conditionally recommended after multidisciplinary discussion for patients with cT2 N0 rectal cancer who:
a. would have a permanent colostomy or inadequate bowel continence after TME AND
b. decline TME AND
c. are found to have ≤ypT1 disease and R0 margins upon LE AND
d. agree to close follow-up by a multidisciplinary team.
(Moderate-quality evidence, Conditional recommendation)
608
For patients with rectal cancer considering NOM or LE after RT, conventional fractionation from 5000-5400 cGy in 25-30 fractions with concurrent chemotherapy is recommended. (Moderate-quality evidence, Strong recommendation)
608
For patients with rectal cancer considering NOM, concurrent chemoradiation with or without induction or consolidation chemotherapy is conditionally recommended. (Moderate-quality evidence, Conditional recommendation)
608
For patients with rectal cancer considering NOM, assessment for response is recommended with rectal protocol MRI, CT abdomen/pelvis, and proctoscopy/sigmoidoscopy with DRE 2-3 months after completion of treatment. (Moderate-quality evidence, Strong recommendation)
608
For patients with rectal cancer undergoing NOM or LE, surveillance is recommended with:
• proctoscopy/sigmoidoscopy with DRE every 3 months for the first 2 years, then every 6-12 months thereafter,
• rectal protocol MRI every 3-6 months for the first 2 years, then every 6-12 months thereafter, and
• cross-sectional imaging of the chest, abdomen and pelvis every 6-12 months for the first 2 years, then every 12 months thereafter.
(Moderate-quality evidence, Strong recommendation)
Implementation remark: Follow-up should continue for a minimum of 5 years.
608

Recommendations for appropriate treatment volumes and techniques

For patients with cT3-4 and/or cN + rectal cancers, inclusion of the rectum, mesorectal nodes, presacral nodes, internal iliac nodes, and obturator nodes in the CTV is recommended. (High-quality evidence, Strong recommendation)
608
For patients with rectal tumors invading an anterior organ or structure (eg, prostate, seminal vesicles, cervix, vagina, and/or bladder), inclusion of the external iliac nodes in the CTV is conditionally recommended in addition to the rectum, mesorectal nodes, presacral nodes, internal iliac nodes, and obturator nodes. (Low-quality evidence, Conditional recommendation)
608
For patients with rectal cancer involving the anal canal, inclusion of inguinal and external iliac nodes in the CTV is conditionally recommended in addition to the rectum, mesorectal nodes, presacral nodes, internal iliac nodes, and obturator nodes. (, Conditional recommendation)
Expert Opinion
608
For patients with rectal cancer treated with RT, an IMRT/VMAT technique is conditionally recommended. (Low-quality evidence, Conditional recommendation)
Implementation remark: IMRT/VMAT may be beneficial when the external iliac nodes and/or the inguinal nodes require treatment or when 3-D conformal techniques may confer a higher risk for toxicity.
608
For patients with rectal cancer receiving IMRT/VMAT, daily image guidance to verify localization is conditionally recommended. (, Conditional recommendation)
Expert opinion
608
For patients with rectal cancer in whom the CTV does not include the inguinal nodes, simulation prone with a belly board is conditionally recommended. (Low-quality evidence, Conditional recommendation)
608

Recommendation Grading

Overview

Title

Radiation Therapy for Rectal Cancer

Authoring Organization

American Society for Radiation Oncology

Publication Month/Year

October 19, 2020

Last Updated Month/Year

September 3, 2024

Supplemental Implementation Tools

Document Type

Guideline

External Publication Status

Published

Country of Publication

US

Inclusion Criteria

Female, Male, Adult, Older adult

Health Care Settings

Ambulatory, Emergency care, Home health, Hospital

Intended Users

Social worker, physician, nurse, nurse practitioner, physician assistant

Scope

Treatment

Diseases/Conditions (MeSH)

D011827 - Radiation

Keywords

rectal cancer, radiation therapy (RT), rectal adenocarcinomas, neoadjuvant therapy