Chemotherapy
with Paul Celano, MD
What are the different stages of colorectal cancer?
Colorectal cancer is one of the most common cancers in the United States and affects almost 160,000 Americans each year causing nearly 65,000 related deaths. Recent medical advances have resulted in an increase in survival rates. At GBMC, physicians strive to offer these latest therapies while providing individualized treatment for every patient.
Colorectal cancer forms in the large intestine and rectum and begins as small, benign polyps, which are often precursors to cancer. Unless they are removed, the polyps can grow to become cancerous tumors.
“Once colorectal cancer is established or suspected, it needs to be removed,” says Paul Celano, MD, Division Chief of Medical Oncology at GBMC. “Surgery is the hallmark treatment for colorectal cancer.”
Depending on the stage and location of the tumor, adjunct treatment such as chemotherapy or radiation therapy may also be used. Staging of colorectal cancer is established at the time of surgery, when physicians can thoroughly evaluate whether the cancer has metastasized (spread). During Stage I, cancer is confined to the mucosa or lining of the colon. In Stage II, the cancer has moved through the mucosa muscle. In Stage III the cancer has progressed to nearby lymph nodes, but is not yet affecting other organs of the body. In Stage IV, the cancer has spread to other parts of the body, including other organs.
Chemotherapy frequently follows surgery and is used to destroy any remaining cancer to prevent a recurrence. “The type of treatment depends on the stage of the colon cancer and the patient’s particular medical situation,” says Dr. Celano. These treatments can range from intensive intravenous chemotherapy over 24 weeks to oral chemotherapy. The most intensive intravenous chemotherapy regimen uses the drug oxaliplatin, which can be the most effective but has numerous side effects. The oral drug, capecitibine, can also be effective with fewer side effects and can be a good alternative for patients who cannot tolerate traditional chemotherapy.
Dr. Celano emphasizes the importance of individualizing treatment for each patient to ensure the best outcome. “With anything in medicine, we need to make sure we use treatments people can tolerate,” he says. “That’s especially important, when we are trying to prevent the spread of the disease.”
Recent advances have improved the survival of patients with Stage IV or metastatic colon cancer. In addition to chemotherapy, the use of targeted monoclonal antibodies has provided significant benefits with less toxic effects. For instance, these newly developed antibodies such as bevacizumab are different from traditional chemotherapy. Rather than killing existing cancer cells, they work to reduce blood flow to the cancer cells.
“These are true antibodies in the sense that they direct themselves against the blood vessels that grow into cancer. They reduce blood flow to the cancer cells and allow the chemotherapy to penetrate the cells better,” says Dr. Celano. Other antibodies such as cetuximab and panitumumab interfere with the epidermal growth factor receptors, a key switch for the growth of colon cancer.
GBMC is currently participating in national clinical trials to provide patients with access to the latest treatments and improve the future care of patients with colon cancer. These studies involve the use of monoclonal antibodies in early stage colon cancer, as well as novel ways of using newer agents for the treatment of advanced colon cancer.
In addition to offering patients innovative treatments, the colorectal cancer experts at GBMC use a team approach. “Once a person is diagnosed, the surgeon, radiation oncologist and medical oncologist get together and develop a treatment plan that is most appropriate for that patient,” says Dr. Celano.
