Professional Statements and Societal Positions Guidelines
Practice Guidelines and Position Statements
National Comprehensive Cancer Network Guidelines
Gastrointestinal Tract Cancers
The NCCN guideline (v.2.2020) for gastric cancer indicates that IMRT "may be used in clinical settings where dose reduction to organs at risk is required, and cannot be achieved by 3D techniques." In addition, target volumes need to be carefully defined and encompassed while taking into account variations in stomach filling and respiratory motion.
The NCCN guideline (v.3.2020) for hepatobiliary cancers states that "All tumors irrespective of the location may be amenable to radiation therapy (3D conformal radiation therapy, intensity-modulated radiation therapy [IMRT], or stereotactic body radiation therapy [SBRT])."
IMRT is mentioned as an option in the NCCN guideline (v.1.2020) for pancreatic adenocarcinoma, stating that IMRT "is increasingly being applied for the therapy of locally advanced pancreatic adenocarcinoma and in the adjuvant setting with the aim of increasing radiation dose to the gross tumor while minimizing toxicity to surrounding tissues." In addition, the guideline states that "there is no clear consensus on the appropriate maximum dose of radiation when IMRT technique is used."
Gynecologic Cancers
For cervical cancer, the NCCN guideline (v.1.2020) indicates IMRT "is helpful in minimizing the dose to the bowel and other critical structures in the post-hysterectomy setting and in treating the para-aortic nodes when necessary." This technique can also be useful "when high doses are required to treat gross disease in regional lymph nodes." IMRT "should not be used as a routine alternative to brachytherapy for treatment of central disease in individuals with an intact cervix." The guideline also mentions that "very careful attention to detail and reproducibility (including consideration of target and normal tissue definitions, individual and internal organ motion, soft tissue deformation, and rigorous dosimetric and physics quality assurance) is required for proper delivery of IMRT and related highly conformal technologies."
The NCCN guideline (v.1.2020) on uterine neoplasms states that radiotherapy for uterine neoplasms includes external-beam radiotherapy and/or brachytherapy but that IMRT may be considered "for normal tissue sparing."
The NCCN guideline (v.1.2020) on ovarian cancer does not mention IMRT.
Anorectal Cancers
The NCCN guideline (v.2.2020) for anal carcinoma states that IMRT "is preferred over 3D conformal RT [radiotherapy] in the treatment of anal carcinoma"; and that its use "requires expertise and careful target design to avoid reduction in local control by so-called 'marginal-miss'."
The NCCN guideline (v.4.2020) on rectal cancer indicates that "...IMRT... should only be used in the setting of a clinical trial or in unique clinical situations such as reirradiation of previously treated individuals with recurrent disease or unique anatomical situations."
American College of Radiology
The American College of Radiology Appropriateness Criteria (2014) recommended that IMRT is usually appropriate to treat anal cancer if performed outside of a protocol setting but is still undergoing study. The College also noted the most appropriate radiation dose for anal cancer has not been determined and quality control and technical problems are considered challenging with IMRT (e.g., in target volume contouring).
American Society for Radiation Oncology
In 2020, the American Society for Radiation Oncology published a clinical practice guideline on RT for cervical cancer. One key question within the guideline asked when it was appropriate to deliver IMRT for women administered definitive or postoperative RT for cervical cancer? Recommendations regarding this clinical scenario included:
- "In women with cervical cancer treated with postoperative RT with or without chemotherapy, IMRT is recommended to decrease acute and chronic toxicity." This was a strong recommendation based on moderate quality evidence for acute toxicity and low quality evidence for chronic toxicity.
- "In women with cervical cancer treated with definitive RT with or without chemotherapy, IMRT is conditionally recommended to decrease acute and chronic toxicity." This was a conditional recommendation based on moderate quality evidence for acute and chronic toxicity.
The guideline also notes that there are "no data that IMRT improves disease-specific survival or OS over 2D/3D techniques."