Radiation therapy is an important part of treatment for several gastrointestinal (GI) cancers. Depending on the type and stage of cancer, it may be used to cure the disease, reduce the risk of recurrence, shrink a tumor before surgery, or relieve symptoms.
Modern techniques such as IMRT, VMAT, IGRT, SBRT and 4D-CT allow radiation to be delivered precisely while protecting nearby healthy organs.
Which Gastrointestinal Cancers Can Be Treated With Radiation?
Radiation therapy may be used for:
- Rectal cancer
- Anal cancer
- Esophageal cancer
- Gastric (stomach) cancer
- Pancreatic cancer
- Liver and bile duct cancers
- Selected cancers of the small intestine and other GI sites
The role of radiation varies depending on the type and stage of cancer.
When Is Radiation Therapy Used?
Radiation may be recommended:
- Before surgery to shrink or control the tumor
- After surgery when there is a significant risk of recurrence
- Along with chemotherapy for certain GI cancers
- As the main treatment for cancers such as anal cancer in selected patients
- As SBRT for selected localized or oligometastatic tumors
- To relieve symptoms such as pain, bleeding or obstruction in advanced cancer
Radiation for Rectal Cancer
Radiation is commonly combined with chemotherapy and/or other systemic treatment for selected locally advanced rectal cancers.
It may be given before surgery to reduce the risk of local recurrence and improve tumor control.
The exact treatment approach depends on the tumor stage, MRI findings, location and response to treatment.
Radiation for Esophageal Cancer
Radiation may be combined with chemotherapy for patients who are:
- Not suitable for surgery
- Receiving treatment before surgery
- Being treated with definitive chemoradiation
Radiation can also be used to relieve difficulty swallowing caused by an advanced esophageal tumor.
Radiation for Anal Cancer
For many patients with anal cancer, chemoradiation is the primary treatment and can avoid the need for major surgery.
Radiation is carefully planned to treat the tumor and nearby lymph nodes while minimizing exposure to surrounding organs.
Radiation for Pancreatic Cancer
Radiation may be considered in selected patients with:
- Borderline resectable disease
- Locally advanced disease
- Selected postoperative or recurrent disease
- Selected localized or oligometastatic disease
SBRT may be an option for carefully selected patients when a highly focused treatment is appropriate.
Radiation for Liver and Other GI Cancers
Highly precise radiation techniques such as SBRT can be used for selected liver tumors and certain metastatic lesions.
Treatment decisions depend on tumor size, number and location of lesions, liver function and proximity to nearby organs.
What Modern Radiation Techniques Are Used?
IMRT & VMAT
Help shape radiation around the tumor while reducing exposure to surrounding organs.
IGRT
Uses imaging before or during treatment to improve treatment accuracy.
4D-CT
Helps assess tumor movement caused by breathing, particularly for upper abdominal tumors.
SBRT
Delivers a high, precisely targeted dose in a small number of treatment sessions.
How Many Sessions Are Needed?
The number of treatments depends on the cancer type and treatment goal.
- Conventional or chemoradiation: Often several weeks
- Short-course radiation: Used for selected cancers such as some rectal cancers
- SBRT: Usually completed in a few sessions
- Palliative radiation: May require only a few sessions or sometimes a single treatment
Your treatment schedule will be individualized according to your cancer and overall health.
What Are the Possible Side Effects?
Side effects depend on the part of the digestive system being treated.
Possible effects include:
- Tiredness
- Nausea
- Reduced appetite
- Loose stools or diarrhea
- Abdominal discomfort
- Bloating
- Skin irritation
- Difficulty swallowing, when the esophagus is treated
Most side effects are temporary and can be managed with medicines, dietary changes and supportive care.
Is Gastrointestinal Radiation Painful?
No. External-beam radiation therapy itself is painless.
You simply lie comfortably on the treatment couch while the radiation is delivered. Each treatment usually takes only a few minutes.
You are not radioactive after external-beam radiation therapy.
Can Radiation Cure Gastrointestinal Cancer?
Yes, in selected patients.
Radiation can be given with curative intent for several GI cancers, particularly when used as part of a carefully planned multidisciplinary treatment.
For advanced disease, radiation may instead be used to control the tumor and relieve symptoms.
Why Choose Modern Radiation Therapy?
GI organs are located close to important structures such as the stomach, bowel, liver, kidneys and spinal cord.
Modern techniques such as IMRT, VMAT, IGRT and SBRT allow radiation to be focused on the tumor while reducing unnecessary radiation to surrounding healthy tissues.
Book a Consultation
If you or a loved one has been diagnosed with a gastrointestinal cancer, a radiation oncology consultation can help determine whether radiation therapy should be part of your treatment plan and which approach is most suitable for you.
