Colorectal Cancer Treatments

How Is Colorectal Cancer Treated?

The most common treatment for colorectal cancer is surgery to remove the tumor. Chemotherapy and radiation therapy are also frequently involved in plans for therapy. In some cases, a combination of all three will be employed.

It’s important to note that at City of Hope there is no one-size-fits-all approach to colorectal cancer. We treat the patient, not the disease, and afford each person the compassion and dignity that everyone deserves. Our nationally renowned physicians will work closely with you and your family to customize your treatment plan according to the characteristics of the disease as well as your own goals, values and preferences.

The City of Hope Difference

Staff performing colorectal surgery | City of Hope
Colorectal surgeons Kurt A. Melstrom, M.D., and Lily Lau Lai, M.D.

City of Hope is one of the few centers in the country that treats colorectal cancer using a comprehensive, team-based approach, with medical experts whose only focus is treating this type of cancer.

Your care includes regular interaction and input from an extraordinary team of colorectal surgeons, oncologists, gastroenterologists, radiologists and pathologists — along with nurses, genetic counselors, nutritionists and specially trained support staff.

That comprehensive approach to your care means better care and a strong potential for you to live longer. Our approach to treating colorectal cancer is focused on precision medicine. That means we apply precise and minimally invasive surgical techniques — and test individual cancer cells to find drug combinations that would work best for your specific cancer.

We are a leader in targeting therapy to individual patients and have many options for treating complex colorectal cancers including:

  • Sphincter-saving surgery that drastically reduces the need for a permanent colostomy
  • Expertise in cancer that has spread to the liver, including combination surgeries with our world-renowned hepatobiliary surgery team
  • Expertise in HIPEC, or hyperthermic intraperitoneal chemotherapy, a treatment that involves removing tumors, then delivering heated chemotherapy directly to the abdomen
  • Clinical studies that are regularly finding new drug therapies and combinations to treat advanced cases

What  Doctors Will I See at My Appointment?

Your care team is likely to include several types of cancer specialists, including:

  • Medical oncologists have special training in diagnosing and treating cancer using chemotherapy, hormonal therapy, biological (immunological) therapy and targeted therapy.
  • Colorectal surgeons are trained in diagnosing and treating cancer and precancerous growths with surgery or endoscopy, an intervention that doesn’t involve incisions. Learn about our Division of Colorectal Surgery.
  •  Radiation oncologists are experts in using radiation therapy to treat patients with cancer.
“I find great satisfaction in identifying a tumor, removing it and restoring the body to normal functioning. My inspiration comes from the individual challenge that each patient brings and finding the best way to treat them.”
Kurt Melstrom, M.D., M.S., colorectal surgeon

What Are the Different Types of Surgeries?

City of Hope is ranked among the Highest Performing Hospitals for Colon Cancer Surgery by U.S. News & World Report 2023-24

City of Hope’s surgeons are world leaders in robotically assisted and other minimally invasive techniques for colorectal surgery. While fighting cancer, they also focus on minimizing damage from surgery and avoiding a permanent colostomy. Our surgeons work on a team to determine the best way to treat your cancer and preserve your bowel function and quality of life.

  • Colon resection, or colectomy, and hemicolectomy involve removing the part of the colon where cancer occurs plus a margin or buffer zone of normal colon tissue on either side, as well as nearby lymph nodes. By removing the tumor and the lymph nodes, this surgery provides the best chance to prevent the cancer from coming back. Sometimes part of the colon needs to be removed; depending on which part, the procedure may be called a segmental colectomy, a hemicolectomy or a sigmoidectomy. Removal of the entire colon is referred to as total colectomy.

    Segmental colectomy and hemicolectomy may be performed in three ways:
    • Open colectomy is performed through an incision in the abdomen.
    • Laparoscopy is performed using long, narrow instruments inserted through small incisions. The instruments contain a video camera to allow the surgeon to see inside the body.
    • Robotic surgery is similar to laparoscopy, but the instruments are moved by a robot that is tightly controlled by the surgeon at a console. The more advanced technology makes it possible to perform most of the surgery internally until a small incision has to be made to remove the tissue from the body.
  • Rectal resection involves removing the last section of the large intestine, a procedure that most commonly can be done so that the anal sphincter muscle is preserved and the bowels reconnected. As with colon resection, we perform most of these surgeries robotically or laparoscopically at City of Hope.
  • Lower anterior resection, or LAR, removes the part of the rectum that has cancer. The colon is then reattached to the remaining rectum.
  • Proctectomy with coloanal anastomosis removes the whole rectum but preserves the sphincter muscle. The colon is then joined to the anus. A temporary stoma allows for the area to heal without stool passing through it.
  • Abdominoperineal resection, or APR, removes the entire rectum and anus, including the sphincter muscle. The site of the anus is completely closed, and a permanent stoma is created.
  • Colostomy or ileostomy is performed when tumors are blocking the colon or when a reconstructed bowel is still healing and not ready for stool. It involves creating an opening in the skin, called a stoma, and connecting the bowel to that opening so that stool can drain into an external bag. Often, a stoma is needed only temporarily and can later be reversed.
  • Polypectomy involves removing a precancerous polyp, for example during a colonoscopy. It does not require an incision.
  • Endoscopic mucosal resection is similar to polypectomy but requires more advanced skills. For polyps that are flat in shape, a surgeon has to work on the growth during colonoscopy in order to ready it for removal by carefully lifting the polyp and injecting a fluid cushion underneath. After that, an endoscopy, a procedure that requires no incision, can be performed to remove and retrieve the growth.
  • Local excision involves removing a rectal polyp or early rectal cancer, including a small rim of healthy tissue around it, through the anus. The procedure does not involve cutting into the abdomen. There are traditional approaches through the anus as well as more sophisticated strategies called transanal endoscopic microsurgery and transanal minimally invasive surgery (TAMIS). In many cases, TAMIS can be conducted using a surgical robot.
  • Radiofrequency ablation is a technique that uses high-energy radio waves to heat and destroy tumors and the area around them that may contain traces of cancer. It is an option for some cancers located where surgery would be too invasive.
  • Endoluminal stents are sometimes used if a tumor has blocked the colon. A stent is a hollow metal or plastic tube that is placed into the colon to stretch and hold it open and relieve the blockage. It’s usually done for a short time to prepare for surgery.
  • Lymphadenectomy is a surgery that involves removing and testing lymph nodes for cancer. It is standard to remove lymph nodes on the cancerous segment of the colon because the disease could spread into those nodes. There are many other lymph nodes left untouched in order to help maintain the body’s immune system.
  • Pelvic exenteration is an extensive surgery that removes the rectum, as well as nearby organs that cancer has spread to, including the bladder, prostate (in those assigned male at birth) or uterus, ovaries and vagina (in those assigned female at birth). Depending on how close the tumor is to the sphincter muscle, the anus may be preserved and the colon joined, as in the coloanal anastomosis procedure described above. Expert urologists then recreate a urine reservoir or reroute the urine to a new external opening.
  • Pelvic floor reconstruction: After certain kinds of colorectal surgery, your care team may recommend pelvic floor reconstruction. During this procedure, our surgical team uses tissue from another part of the body to reconstruct the pelvic floor. This type of reconstructive surgery can sometimes be performed at the same time as your cancer surgery, reducing the need for multiple operations. The initial rest period is typically six to eight weeks. Pelvic floor reconstruction surgery helps reduce the risk of complications and improve quality of life. Learn more about pelvic floor reconstruction

Chemotherapy or radiation may be given before surgery to shrink the tumor, and after surgery to try to wipe out any remaining cancer cells.


Chemotherapy is a treatment that uses drugs to either kill cancer cells or stop them from growing.

Exciting advances in chemotherapy at City of Hope are allowing patients with advanced disease to get combinations of drugs to shrink tumors, making it easier to take them out later with surgery — or melt them away and avoid surgery altogether. If you have failed all standard chemotherapy, City of Hope has several experimental approaches — including immunotherapy and targeted therapy — designed to target your specific tumor and extend your life. And for cancer that has spread to the liver, we offer leading-edge therapies like hepatic arterial infusion: a small disc implanted under the skin that sends chemotherapy drugs directly into the artery that feeds the liver.

HAI: Hepatic arterial infusion allows high-dose chemotherapy to be delivered directly to the liver after surgery for high-risk cancer that has spread beyond the liver. It is also used to treat colorectal cancer that has returned after treatment and spread to the liver. Additionally, HAI can be applied to shrink tumors that spread to the liver from the colon or rectum in patients for whom initial treatment with chemotherapy didn’t reduce tumors enough.

HIPEC and PIPAC: When advanced colorectal cancer spreads to the inner lining of the body cavity, treatment can become especially difficult. In select patients, we offer hyperthermic (or heated) intraperitoneal chemotherapy (HIPEC). Additionally, City of Hope is among the first U.S. centers to offer pressurized intraperitoneal aerosolized chemotherapy (PIPAC).

Both treatments use an alternative route for delivering chemotherapy. Rather than infusing the medications through a vein, chemo is administered during surgery. This strategy may increase survival for patients facing hard-to-reach tumors. We currently treat cancers of the colon, rectum, appendix, ovary and stomach with HIPEC and PIPAC.

Targeted Therapies

City of Hope uses the latest targeted therapies, which are designed to attack specific features of cancer cells. Unlike chemotherapy, which can target both healthy cells and cancer cells, targeted therapies home in on the specific proteins or cell functions that allow cancer cells to grow.

Targeted therapies can either be used as part of standard therapy or delivered through clinical trials against both common and rare gene changes seen in tumors. The gene changes that targeted therapies can address include MSI-H, RAS mutations, BRAF mutations and PIK3CA mutations. Doctors at City of Hope use the latest technology to spot specific mutations in cancer cells so that we can choose the drugs or drug combinations that are most likely to be successful for a specific cancer type.


Immunotherapy, also known as biological therapy, uses the body’s own immune system to fight cancer. Cancer cells can trick the immune system so that it does not attack them. Immunotherapy works in a variety of ways to help the immune system spot and destroy colorectal cancer cells.

There are approved treatments of this type that are highly effective against MSI-H tumors. Additionally, City of Hope offers clinical trials of a variety of checkpoint inhibitor combinations and cellular therapies for MSS mutations in colorectal cancer that has spread, which tends to resist other immunotherapies.

Radiation Therapy

Radiation therapy uses high-energy radiation to kill cancer cells and shrink tumors. City of Hope offers advanced radiation treatments that are highly targeted to cancer cells, including:

  • Brachytherapy (internal beam radiation) involves placing a radioactive source inside your rectum close to the tumor to deliver radiation internally.
  • 3D conformal radiation therapy shapes the radiation beams to conform to, or match, the shape of the tumor.
  • Intensity-modulated radiation therapy is an advanced type of radiotherapy that uses computer-controlled devices for delivering radiation, called linear accelerators, to manipulate the intensity of beams so that they conform to the shape of a tumor.
  • Stereotactic body radiation treatment delivers very high doses of radiation in each treatment to precisely cover cancers, with an entire course of treatment delivered in up to five visits.
  • Image-guided radiation therapy uses imaging techniques, such as MRI and CT, to help radiation oncologists accurately identify the specific area to focus the radiation.
  • Radioembolization involves injecting small radioactive beads into the blood vessels. The beads lodge in blood vessels near the tumor and emit radiation over several days.