Colorectal Cancer Research

Mayo Clinic Cancer Center leads the field in researching colorectal cancer, looking for causes and new ways to prevent colorectal cancer as well as ways to improve treatments.

Recent studies suggest that certain drugs may help prevent colorectal cancer, and a number of ongoing clinical trials are testing various options. Colorectal cancer research in the GI Program includes work in the areas of:

Prevention
Studies indicate that a diet high in fruits and vegetables may lower colorectal cancer risk, as well as the risk of several other diseases. Mayo Clinic has significant cancer prevention expertise, and studies are being done on a number of lifestyle intervention strategies for colorectal cancer, including earlier detection; and also possible preventive therapies, including fiber supplements, vitamins or minerals. Paul Limburg, M.D., leads the colorectal cancer prevention research efforts at Mayo Clinic Cancer Center.

Screening and Diagnosis
Investigative teams lead by researchers including David Ahlquist, M.D.; and C. Daniel Johnson, M.D.; are testing new ways to check for polyps and colorectal cancer — ones that will be more palatable for the patient but still effective. One study is looking at the usefulness of virtual colonoscopy (also known as CT colonography). This uses a computed tomography (CT) scan of the colon, rather than the invasive colonoscopy, to determine the presence of colon cancer. Another study is using genetic testing to check stool samples for colorectal cancer cells.

Specializing in prevention, screening and diagnosis, Mayo Clinic's Colorectal Neoplasia Interest Group maintains a robust registry of patients and families, which helps to identify people at high risk for development of colorectal cancer. It is also a key component of research into new drugs and screening techniques.

Surgical Treatment
Surgery is the primary treatment for most patients with colon and rectal cancer. Researchers at Mayo have made major advances in the field of minimally invasive approaches to colon cancer using laparoscopic techniques. Ongoing research conducted by senior surgical investigators Heidi Nelson, M.D., and Bruce Wolff, M.D., seek novel and minimally invasive approaches to treating rectal cancer, including both laparoscopic surgery and local excision. One current trial will evaluate whether the use of capecitabine and oxaliplatin together with radiation therapy prior to surgery might allow patients with Stage I disease to undergo local excision as an alternative to bowel resection.

Medical and Radiation Treatment
Chemotherapy and radiation therapy are often combined with surgery in patients whose initial cancer has an increased risk of relapse if treated with surgery alone, such as when the tumor extends beyond the colon wall or lymph nodes are involved. GI Program researchers are studying chemotherapy, biological therapy, radiation therapy and combinations of treatments. Some of our leading researchers in this area include Steven Alberts, M.D.; James Martenson, M.D.; and Axel Grothey, M.D.

Some research is testing new chemotherapy drugs or drugs that are now used against other cancers (such as cisplatin or gemcitabine), to determine their effectiveness against colorectal cancer. Other studies are looking at ways to combine drugs already known to be active against colorectal cancer to improve their effectiveness. Still other studies are testing the best ways to combine chemotherapy with radiation therapy and/or immunotherapy.

Gregory Wiseman, M.D., has an open clinical study looking at radioembolization to treat metastases. Other investigators are research biological therapy, or immunotherapy, using the body's natural ability (immune system) to fight cancer. For example, monoclonal antibodies, a substance made in the laboratory that can bind to cancer cells, can be administered after surgery or with chemotherapy to kill cancer cells.

Genetics
Scientists are learning more about some of the inherited and acquired changes in DNA that cause cells of the colon and rectum to become cancerous. Recent discoveries of inherited genes that increase a person's risk of developing colorectal cancer are already being used in genetic tests to inform people most at risk.

Advances in understanding how these genes work are expected to eventually lead to new drugs and gene therapies to correct these gene problems. Researchers Noralene Lindor, M.D.; Stephen Thibodeau, Ph.D.; E. Aubrey Thompson, Ph.D.; and Lisa Boardman, M.D.; are leading Mayo’s efforts in this area.

Tumor growth factors
Naturally-occurring substances in the body that promote cell growth, called growth factors, activate cells by attaching to growth factor receptors, which are present on the outer surface of the cells. Some cancer cells grow especially fast because they contain more growth factor receptors than normal cells do. GI Program researchers involved in these studies include Vijay Shaj, M.D., and Frank Sinicrope, M.D.

Epidemiology
The study of populations to determine factors that affect the general health of these populations as well as those that may play a causal role in illness, epidemiology research is a robust endeavor of Mayo Clinic Cancer Center. Findings generated from this type of research serve as the foundation for screening and prevention initiatives. Through epidemiological research, evidence-based medicine develops. Epidemiologists identify risk factors for cancer, and further research seeks to define the best course of treatment for a particular cancer as well as to find the best treatment for each individual. GI Program initiatives in this area are led by a number of researchers including Dr. Limburg and Susan Slager, Ph.D.