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Advanced Radiation Therapy for Colorectal and Anal Cancer


Colorectal cancer is the third most common cancer besides skin cancer found in both men and women. But the colon cancer survival rate is fairly high. Thanks to improvements in prevention, early detection, and treatment, more than a million people in the US are survivors of colon or rectal cancer.

MRO has been awarded full accreditation in excellence of care and safety by the American Society of Radiation Oncology APEx program.


Anal cancer is less common. Over 90% of anal cancer is caused by human papilloma virus (HPV), according to the Anal Cancer Foundation. Radiation therapy plays a prominent role in anal cancer treatment.

FAST FACT Graphic. 
One in 22 men and one in 24 women will be diagnosed with colorectal cancer in their lifetime. - American Cancer Society

If you’ve been diagnosed with cancer, you can find leading-edge technology and therapy close to home, at Minneapolis Radiation Oncology. MRO is the Twin Cities’ leading provider of advanced radiation therapy for cancer, with 11 locations across the Twin Cities, Brainerd Lakes Area, and Western Wisconsin. Since 1981, our radiation oncology specialists have treated over 100,000 patients – more than any other clinics in Minnesota.

Our MRO radiation oncologists provide a level of expertise that comes from working exclusively with radiation cancer treatments every day. And we’ve established a reputation as trusted allies in the fight against cancer. Count on the cancer specialists at MRO to be here for you with care, comfort, and compassion.

“My patients inspire me with their courage and commitment to getting the treatment they need. Patient care is my passion and my calling.”
Raul Fernandez-Gonzalez, MD
MRO | Fairview Ridges

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What is colorectal and anal cancer?

Colorectal cancer is the term for cancers found in the colon or the rectum, which make up the large intestine; the cancers share many characteristics, symptoms, and treatments.

Anal cancer forms within the anal canal, just below the rectum. It’s typically a different type than colorectal cancer, often treated without surgery. But the radiotherapy treatment is similar to that of rectal cancer.

The treatments and side effects of these diseases may impact your quality of life. That’s why it’s important to turn to doctors with expertise in colorectal and anal cancers like the doctors at MRO, who will work to help you understand the disease and to see if radiation therapy is the right choice for you.

Types of colorectal and anal cancer

About 95% of cancers found in the colon and the rectum are adenocarcinomas, which start in the cells lining the colon or rectum. Anal cancers are most commonly squamous cell carcinomas.

Why choose radiation therapy?

Your oncologist may suggest radiation therapy as a treatment option for colorectal or anal cancer for a number of reasons, including:

  • With anal cancer, radiotherapy is often the primary treatment, so you may avoid surgery altogether.
  • Radiation before surgery may help shrink tumors, so they are easier to remove.
  • After surgery, radiation therapy may help kill cancer cells that have been left behind.
  • Radiation therapy may be an option for patients who are unable to undergo surgery.
  • When used as palliative treatment, radiation therapy helps to shrink tumors that may be causing a blockage in the colon or intestines.
  • Radiation therapy is often given in conjunction with chemotherapy.
For patients diagnosed with localized-stage colorectal cancer, the 5-year survival rate is 90%.  - American Cancer Society, Colorectal Facts and Figures, 2015-2019©

Radiation technology is proven effective

At MRO, we use radiation, or radiotherapy, to destroy cancer cells. Using state-of-the-art imaging technologies such as MRI, CT, and PET, your MRO care team can pinpoint radiation doses down to the millimeter.

When radiation therapy is a treatment option for you, your MRO care team will work closely with your oncology care team to keep you and your family fully informed about colorectal and anal cancer and treatment options.

There are several different techniques used in colon cancer treatment, but each of the treatments directs precise doses of radiation at cancer cells, which are more susceptible to radiation than healthy cells. Like an x-ray, radiation therapy is painless. There’s no fear of becoming radioactive during or after treatment.

“My goal is to provide the best treatment possible for each of my patients using state-of-the-art technology combined with personal care and attention. I aim to treat each of my patients as if they were a family member, by informing and supporting them throughout their treatment and beyond.”
Kurt Nisi, MD
MRO | North Memorial

While the statistics for colon cancer are fairly equal in men and women, a larger number of men than women are diagnosed with rectal cancer.

Radiation treatment for colorectal and anal cancer

At MRO, you have access to some of the most advanced technology available for cancer treatment. Using state-of-the-art imaging technologies, MRO doctors, dosimetrists, and physicists can pinpoint radiation for colon cancer down to the millimeter.

For rectal cancer, radiation therapy may be used before surgery to shrink the tumor so that it’s easier to remove. Radiation therapy may also be used after surgery to destroy any remaining cancer cells. Both approaches have worked to treat this disease. Chemotherapy is often given at the same time as radiation therapy, called chemoradiation therapy, to increase the effectiveness of the radiation therapy.

Common types of radiation therapy include:
External beam radiation therapy (EBRT): EBRT delivers high doses of radiation to cancer cells from outside the body, using a variety of machine-based technologies.

3-D conformal radiation therapy is a technique where the beams of radiation used in treatment are shaped to match the tumor, using targeting information to focus precisely on the tumor.

Intensity modulated radiation therapy (IMRT): An advanced form of 3D therapy. First, a treatment plan is optimized in the computer planning system. During treatment, the machine moves around you as it delivers radiation. It shapes the beams and adjusts the intensity of the beams from all angles to limit the dose reaching nearby healthy tissues.

Stereotactic radiation therapy: Stereotactic radiation therapy, also known as stereotactic ablative radiotherapy (SABR), is a type of external-beam radiation therapy that may be used if a tumor is metastatic, which means it has spread to other parts of the body. Instead of giving a small dose of radiation each day for several weeks, SBRT uses very focused beams of high-dose radiation given in fewer treatments. Several beams are aimed at the treatment area from different angles.

Other types of radiation therapy. For some people, specialized radiation therapy techniques may help get rid of small areas of cancer that could not be removed with surgery.

Intraoperative radiation therapy: A single high dose of radiation therapy given during surgery.

Brachytherapy: The use of radioactive “seeds” placed inside the body.

“When I was diagnosed with anal cancer, I turned to my faith. Then I turned to MRO. Everyone helped me through my journey. I knew I was going there for treatment, but it was just a joy to go. It was like going to see some friends that cared about me.”
Ron | Anal cancer patient

Up to 30% of colorectal cancer patients have a family history of the disease, about 5% of which are due to an inherited genetic abnormality. People with a parent, sibling, or child who has been diagnosed with CRC have 2 to 4 times the risk of developing the disease compared to people without this family history. - American Cancer Society

What to expect at your first appointment

We’ll start with a consultation appointment lasting one or two hours. During that time you’ll meet with a radiation oncologist to make sure radiation is the right choice for you.

Once the radiation oncologist has examined you, he or she will discuss treatment options and the pros and cons of radiation treatment.  A radiation therapy nurse will also be there to help explain treatment, discuss how often radiation therapy is given, and provide information on how to take care of yourself during treatment.

Since radiation therapy for cancer requires the utmost precision, you’ll also go through a simulation at the MRO Therapy Center. Using image mapping as a guide, your care team will position you as you would be for treatment and take measurements to build a targeted treatment plan and pinpoint the radiation for the best possible outcome.

For questions to ask your provider, see our FAQ page.

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“Radiation Oncology is my passion, as is helping others. I have a multi-cultural background and I understand how differently diverse cultural groups approach a cancer diagnosis. My goal is to provide the best, most compassionate care, in a way that’s appropriate to my patients’ needs.”
Raul Fernandez-Gonzalez, MD
MRO | Unity
MRO | Fairview Ridges

We make treatment as easy as possible, so you can get back to living your life

At Minneapolis Radiation Oncology, we understand the uncertainty that comes with a colorectal or anal cancer diagnosis. Our oncologists and supportive care teams are committed to helping you understand the complexities of the disease and how radiation treatment may help with your cancer.

Your own treatment will depend on the type of tumor you have, where it’s located, and what type of technology we’ll be using. Your treatment schedule at MRO will be specifically tailored to you, and treatment will take place at the clinic that is most convenient for you. You’ll also meet with your physician each week to monitor progress and touch base with your nurse, who can answer any questions you may have.

Managing side effects of radiation treatment for colorectal and anal cancer

Your MRO care team will talk with you about the possible side effects of your radiation therapy regimen. Most side effects go away soon after treatment is finished, but may include:

  • Fatigue
  • Nausea and vomiting
  • Loss of appetite and weight loss
  • Skin irritation in the area being treated, ranging from mild redness to blistering and peeling
  • Diarrhea and bloody stools

How to care for yourself during treatment

At MRO, we understand that there’s more to recovery than medical treatment. And while radiation therapy itself may be painless, it impacts your body in ways that you can’t always see. In order to keep your body strong, we encourage you to be active in caring for yourself. Here’s a list of things you can do to get the most out of life during your treatment:

  • Drink plenty of fluids and eat a healthy diet.

  • Listen to your body. Don’t push yourself too hard, and rest when you’re tired. You will probably be sleeping more than normal, and that’s okay.

  • Be kind to the skin near your treatment area. Wash the area with mild soap and water, and do not put hot or cold packs on the skin. Contact your MRO care team before using lotions or ointments.

  • Find a support group or seek out help to manage the stress that comes with cancer treatment and a cancer diagnosis.

  • Make sure to tell your doctor about any medicines or supplements you take to ensure they are safe to use during treatment.

  • Follow your doctor’s orders and contact your MRO care team with any questions.

Life after treatment

Living with colorectal or anal cancer can necessitate changes in your lifestyle; it’s all about finding the quality of life that suits you best. After you’ve completed treatment, you’ll have follow-up visits with your MRO radiation oncologist and the doctor who referred you to MRO, especially in the first few months after treatment, to make sure there is no progression or recurrence. During this time, it’s important to report any new symptoms to your doctor right away so the cause can be found and treated.

Follow-up care varies from patient to patient. Your physician may also recommend home care, occupational or vocational therapy, pain management, physical therapy, or participation in support groups.For more information, visit our resources page.

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