Colon Surgery – Colon Cancer Treatment


Surgery is the mainstay of therapy for colon and rectal cancer and is often the only treatment that is needed. In other cases, the best results are obtained with a combination of surgery, radiation and chemotherapy.

Washington University colon and rectal surgeons at the Siteman Cancer Center have pioneered “sphincter-sparing” surgical techniques that allow most patients with rectal cancer to be treated successfully without a colostomy, a procedure that creates an opening in the abdomen for the drainage of stool.

Our surgeons also are leaders in developing minimally invasive laparoscopic surgery techniques to treat colon and rectal cancer without making a large incision. Radiation therapy may be used to kill cancer cells and shrink tumors. Chemotherapy uses drugs given by mouth or intravenously to kill cancer cells.

The lower gastrointestinal physician team treats more than 650 patients yearly with colon, rectal and anal cancers. To treat the conditions effectively, specific diagnosis and staging are of the utmost importance. Depending on the biology and genetics of the tumor, patients will often be recommended to have neoadjuvant radiation and/or chemotherapy before surgery. Determining the need for neoadjuvant treatment involves careful treatment planning and incorporating location, stage, depth of the cancer in the colon wall and whether lymph nodes are involved. Pelvic MRI gives surgeons the most information, revealing most clearly the circumferential margins of the tumor and how close it comes to outer edges of surgery without long-term consequences. Learn more about surgery at the Siteman Cancer Center.

Colon surgery

More than 60 percent of colorectal surgeons’ patients have laparoscopic surgery, which has been found to be as safe and effective as standard incisional open surgery for cancer confined to the colon.

Preventive colon surgery: Patients with familial adenomatous polyposis (FAP) can have hundreds or thousands of colon polyps before age 18-22, so the best way to prevent the cancer is to remove the colon.

Rectal/anal surgery

Ten to 15 years ago, tumors in the lower third of the rectum usually required taking out the anal sphincter muscle and giving the patient a colostomy, a drainage site routed to the abdomen where a bag collected solid waste. Now surgeons understand that any cancer not directly involving the sphincter muscle or pelvic floor, and with enough distance between it and normal tissue to achieve a clear margin, makes it possible to preserve normal bowel function.

Careful treatment planning and analysis of the tumor gives the surgeon important information about whether a short course of radiation for five days, followed by immediate surgery, would be the treatment of choice. The current standard of care is a long course of radiation and chemotherapy for five weeks with an eight week recovery period, followed by surgery. For the appropriate candidates, both approaches show a decrease in local recurrence and no difference in long-term survival.

Another option is to start with chemotherapy alone. Not all tumors respond to radiation or the combination of radiation and chemotherapy. There are many different treatment regimens for patients with rectal cancer to individualize their care. The majority of rectal cancer patients are eligible for clinical trials.

Transanal endoscopic microsurgical (TEM) excision is a surgery only offered at Siteman that allows for the removal of benign polyps and early cancers from the anal area. The approach is minimally invasive and allows better visualization and access to nearby lesions than traditional methods. It is also being used in appropriate patients to remove more advanced cancers in conjunction with radiation therapy.

Treating rectal cancer is a delicate balance between getting rid of the cancer and optimizing bowel function. That requires doctors who collaborate as ours do. However, despite all the latest clinical trials, imaging and treatment modalities, a small percentage of patients will still need colostomies and will have the support of experienced enterostomal therapists to help them learn to manage them.

Medical treatments for colon cancer

Most chemotherapy is given after surgery. Data going back almost 15 years show that chemotherapy after surgery improves the survival rate of patients with colon and rectal cancer by about 30 percent. For patients with cancer that has spread (metastatic), chemotherapy can improve survival and quality of life. Chemotherapy and radiation may both be given after surgery. When patients receive standard therapy for their tumor, they may also be advised to add a clinical trial drug to be given at the same time to improve survival rates.

Radiation treatments for colon cancer

Radiation’s role in the treatment of colorectal cancer is primarily to:

  1. Treat rectal cancer that has a high chance of recurring with surgery alone.
  2. Treat a cancer that has spread from the rectum or colon to other organs, like the liver. In some cases stage 4 colon cancer can spread to the brain, and in those cases Gamma Knife may be a therapy used.