Colon Cancer: Treatments
Treatment for colon and rectal cancers depend on the size and location of the tumor as well as other factors. A team of Johns Hopkins experts evaluate each patient to develop an individualized treatment plan based on the specific characteristics of the tumor. These doctors may order x-rays, ultrasound, a CT scan, and blood tests to determine the extent of the disease. This evaluation is an important step in helping the medical team design the best and most effective treatment regimen. Treatment plans may include a single therapy or combination of therapies including surgery, chemotherapy and radiation therapy.
When colon cancer is detected in an early stage, it is most commonly treated with a surgical procedure called a colectomy. The surgeon removes the part of the colon that contains the cancer as well as a small portion of surrounding normal tissue. In all but the rarest cases, the surgeon is able to reconnect the healthy sections of the colon and rectum, and bowel function soon returns to normal. If the cancer is completely removed during surgery, and pathologists determine that it was an early stage cancer, no further treatment is needed.
If surrounding tissue is found to contain any cancer cells, the doctors will likely recommend adjuvant chemotherapy. treatment with anticancer drugs. The drugs are given intravenously and/or orally and travel through the bloodstream to destroy tumor cells that may have broken away from original tumor and could begin to grow again elsewhere in the body. Sometimes chemotherapy is given prior to surgery to shrink a tumor and reduce the extent of surgery. This is called neo-adjuvant therapy. Chemotherapy is also given when the cancer has spread beyond the scope of surgery.
Oral or intravenous chemotherapy may be part of the treatment for stage 3 colon cancer after surgery. Patients receive the drugs over a continuous number of days or several times a week, usually for six months after surgery. Chemotherapy may be recommended for stage 4 cancers even if a patient has not undergone surgery.
Some of the most common intravenous chemotherapy used to treat stage 4 colon cancer are combinations of drugs called FOLFOX and FOLFIRI.
Other medicines for patients with advanced colon cancers include drugs that target tumor blood vessel growth, such as bevacizumab, and antibody drugs, such as cetuximab and panitumumab, that block the action of a protein called eGFR that helps cancer cells grow.
Immunotherapy refers to medical treatments that harness or strengthen the body’s own immune defense system against cancer cells. Johns Hopkins researchers led the first clinical trials of one type of immunotherapy, known as immune checkpoint inhibitors, and are continuing their work through the Bloomberg~Kimmel Institute for Cancer Immunotherapy.
For stage 4 metastases to the liver, Johns Hopkins medical oncologists may work with radiation oncologists to perform a procedure called chemoembolism, which delivers chemotherapy directly through the artery that supplies blood to the liver tumor.
Unlike rectal cancer, radiation therapy is not used as a primary treatment for colon cancer. The colon is not a fixed structure inside the body — the bowel naturally moves around — making it more difficult to target accurately with radiation. Radiation therapy is not recommended for stage 1 and 2 colon cancers.
For stage 3 and stage 4 colon cancers, radiation therapy may be used in combination with surgery and medical therapies to target tumors in fixed places close to the colon, such as the abdominal wall, or in distant organs such as the lungs or liver.
If there are only a few limited areas of metastases in stage 4 colon cancer, the Johns Hopkins team will consider an aggressive approach to radiation oncology to increase a patient’s long-term survival. For liver metastases, for instance, radiation oncologists may use stereotactic body radiation therapy (SBRT), a computer-guided, short-term, high-dose radiation treatment.
Liver metastases may also be treated with a type of radiation therapy called radioembolism, in which radioactive beads are injected into the artery that supplies blood flow to the tumor in the liver. This high-dose radiation therapy specifically targets tumor tissue without damaging surrounding healthy liver tissue.
Surgery to remove tumors is the most common treatment for colon cancer, especially early stage cancer that is contained in the colon. About 95 percent of stage 1 and 65 to 80 percent of stage 2 colon cancers are curable by surgery. The main goals of colon cancer surgery are to remove the cancer completely and to reconstruct the bowel if necessary.
This type of surgery is called a colectomy. The bowel is divided into sections based on the different arteries that supply blood to each part of the bowel. Surgery removes the part of the colon with the cancer and then rejoins the remaining colon and its blood supply. Depending on the location of the tumor, more than one part of the colon may be removed.
The Johns Hopkins colon cancer team has specific expertise in minimally invasive colon surgeries, such as laparoendoscopic surgery. This type of surgery requires small incisions in the abdomen through which surgical instruments are inserted and used with the guidance of a small camera. Endoscopy is also used at Johns Hopkins to remove flat colon polyps (clumps of cells inside the colon that could develop into colon cancer) that are difficult to remove with other methods. Some of our surgeons also use robotically guided surgical techniques to precisely identify and remove colon cancers.
Certain types of stage 4 colon cancer may spread into the peritoneal cavity, the space between a membrane layered on the abdominal wall and a membrane around the abdominal organs. To treat this, surgeons at Johns Hopkins may use an aggressive approach that involves cytoreductive surgery to remove as many of the cancerous cells as possible from this space. Cytoreductive surgery may be followed by a highly concentrated, heated type of chemotherapy called hyperthermic intraperitoneal chemotherapy (HIPEC), which is delivered directly to the abdomen.