Colon cancer is classified as Stage IV if the final evaluation following surgical removal of the cancer shows that the cancer has spread to distant locations in the body; this may include the liver, lungs, bones, distant lymph nodes or other sites. While it is commonly thought that patients diagnosed with Stage IV colon cancer have few treatment options, certain patients can still be cured of their cancer, and others can derive significant benefit from additional treatment.
Patients with Stage IV colon cancer can be broadly divided into two groups:
Those with widespread, metastatic cancer that cannot be treated with surgery (sometimes called unresectable cancer )
Those with cancer that has metastasized to a single site
When the site of metastasis is a single organ (such as the liver), and the cancer is confined to a single defined area within the organ, patients may benefit from local treatment directed at that single metastasis.
The majority of patients diagnosed with Stage IV colon cancer have unresectable or widespread disease. Historically, treatment outcomes for these patients were poor. However, new combinations of chemotherapy drugs and the addition of targeted therapies such as Avastin® (bevacizumab) have improved outcomes.
The following is a general overview of treatment for Stage IV colon cancer. Treatment may consist of surgery, radiation, chemotherapy, targeted therapy, or a combination of these treatment techniques. Multi-modality treatment, which is treatment using two or more techniques, has become an important approach for increasing a patient’s chance of cure or prolonging survival. In some cases, participation in a clinical trial utilizing new, innovative therapies may provide the most promising treatment. Circumstances unique to each patient’s situation may influence how these general treatment principles are applied.
The information on this website is intended to help educate patients about their treatment options and to facilitate a mutual or shared decision-making process with their treating cancer physician.
This section covers the initial, also called first-line, treatment of Stage IV colon cancer. For information about the treatment of cancer that has recurred or progressed after initial treatment, visit Recurrent Colon Cancer.
CHEMOTHERAPY FOR WIDESPREAD, METASTATIC COLON CANCER
For over 30 years the chemotherapy drug fluorouracil (5-FU) was the standard treatment for metastatic Stage IV colon cancer that had spread to several sites in the body. 5-FU is typically administered with leucovorin, a drug that is similar in structure and function to the essential vitamin folic acid. Leucovorin (LV) enhances the anticancer effects of fluorouracil by helping the chemotherapy drug bind to and stay inside the cell for a greater period of time, producing longer lasting anticancer effects.
More recently, the addition of other drugs to 5-FU/LV has been found to provide additional benefit. Not all patients can tolerate these multi-drug regimens, however, and less intensive regimens are available.
Adding Targeted Therapy to Chemotherapy
Targeted therapies are anticancer drugs that interfere with specific pathways involved in cancer cell growth or survival. Some targeted therapies block growth signals from reaching cancer cells; others reduce the blood supply to cancer cells; and still others stimulate the immune system to recognize and attack the cancer cell. Depending on the specific “target”, targeted therapies may slow cancer cell growth or increase cancer cell death. Targeted therapies may be used in combination with other cancer treatments such as conventional chemotherapy. Recently approved targeted therapies represent the most novel advance in the treatment of metastatic colorectal cancer in the last few years.
Targeted therapies that have shown a benefit for selected patients with metastatic colorectal cancer include Avastin® (bevacizumab), Erbitux® (cetuximab), and Vectibix® (panitumumab). Avastin blocks a protein (VEGF) that plays a key role in the development of new blood vessels. By blocking VEGF, Avastin deprives the cancer of nutrients and oxygen and inhibits its growth. Erbitux and Vectibix slow cancer growth by targeting a protein known as EGFR. Cancers with certain gene mutations are unlikely to respond to Erbitux or Vectibix, and tests are available to detect these mutations before treatment decisions are made.
TREATMENT OF COLON CANCER THAT HAS METASTASIZED TO A SINGLE SITE
Stage IV colon cancer commonly spreads to the liver or the lungs. Some patients who have cancer that has spread to a single area are candidates for surgery to remove the metastases.
Treatment of the liver: When it’s possible to completely surgically remove all liver metastases, surgery is the preferred treatment. Although surgery offers some patients the chance for a cure, a majority of patients with liver metastases are not candidates for surgery because of the size or location of their tumors or their general health. Some of these patients may become candidates for surgery if initial treatment with chemotherapy shrinks the tumors sufficiently. If the tumors continue to be impossible to remove surgically, other liver-directed therapies may be considered. These other therapies include radiofrequency ablation (use of heat to kill cancer cells), cryotherapy (use of cold to kill cancer cells), delivery of chemotherapy directly to the liver, and radiation therapy. Relatively little information is available from clinical trials about the risks and benefits of these other approaches, but they may benefit selected patients.1
TREATMENT OF THE ELDERLY
A large percentage of patients with advanced colorectal cancer are 65 years or older. Because elderly patients commonly have concurrent illnesses or other medical difficulties that are perceived to exacerbate the side effects of chemotherapy, elderly patients are often treated with reduced doses of chemotherapy. Clinical studies have shown, however, that elderly patients get the same benefit from chemotherapy treatment as younger patients.
While a dose reduction or delay may sometimes be necessary, it may also compromise the optimal treatment of some patients. All patients over 65 should be closely monitored for toxic side effects of chemotherapy, especially during their initial chemotherapy administration cycle.
STRATEGIES TO IMPROVE TREATMENT OF STAGE IV COLON CANCER
The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. Future progress in the treatment of Stage IV colon cancer will result from the continued evaluation of new treatments in clinical trials. Participation in a clinical trial may offer patients access to better treatments and advance the existing knowledge about treatment of this cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. Areas of active exploration to improve the treatment of Stage IV colon cancer include the following:
New Approaches to Treating Liver Metastases: Researchers continue to explore news ways to treat cancer that has spread to the liver. One approach that is being evaluated is radioembolization This strategy uses radioactive microspheres (small spheres containing radioactive material). The small spheres are injected into vasculature of the liver, where they tend to get lodged in the vasculature responsible for providing blood and nourishment to the cancer cells. While lodged in place, the radioactive substance spontaneously emits radiation to the surrounding cancerous area while minimizing radiation exposure to the healthy portions of the liver.2 Researchers are also exploring alternatives to radiofrequency ablation for the destruction of liver tumors, as well as new approaches to delivering chemotherapy to the liver.
New Chemotherapy Regimens: Development of new multi-drug chemotherapy treatment regimens that incorporate new or additional anti-cancer therapies is an active area of clinical research.
New Approaches to Targeted Therapy: Targeted therapies such as Avastin, Erbitux, and Vectibix already play a role in the treatment of selected patients with advanced colorectal cancer, but researchers continue to explore new targeted therapies as well as new ways of using existing drugs. Developing tests to predict which patients are most likely to respond to which drugs is also an important focus of research. Tests to identify certain gene mutations in the cancer are already available, and can help guide the use of Erbitux and Vectibix.
Managing Side Effects: Techniques designed to prevent or control the side effects of cancer and its treatments are called supportive care. Side effects not only cause patients discomfort, but also may prevent the delivery of therapy at its planned dose and schedule. In order to achieve optimal outcomes from treatment and improve quality of life, it is imperative that treatment is delivered as planned and that side effects resulting from cancer and its treatment are appropriately managed. For more information, go to Managing Side Effects.
Phase I clinical trials: New chemotherapy drugs continue to be developed and evaluated in patients with recurrent cancers in phase I clinical trials. The purpose of phase I trials is to evaluate new drugs in order to determine the best way of administering the drug and whether the drug has any anticancer activity in patients.
REFERENCES
1 Alsina J, Choti MA. Liver-directed therapies in colorectal cancer. Seminars in Oncology. 2011;38:651-567.
2 Hendlisz A, Van den Eynde M, Peeters M, et al. Phase III Trial Comparing Protracted Intravenous Fluorouracil Infusion Alone or With Yttrium-90 Resin Microspheres Radioembolization for Liver-Limited Metastatic Colorectal Cancer Refractory to Standard Chemotherapy. Journal of Clinical Oncology. 2010;28:3687-94.
Following surgical removal of colon cancer, the cancer is classified as Stage III if the final pathology report shows that the cancer has spread to the lymph nodes but not to distant sites in the body.
The following is a general overview of treatment for Stage III colon cancer. Treatment may consist of surgery, chemotherapy, targeted therapy (drugs which act by a different mechanism than chemotherapy to target tumor cells) and/or radiation. Multi-modality treatment, which is treatment using two or more techniques, is increasingly recognized as an important approach for increasing a patient’s chance of cure or prolonging survival.
In some cases, participation in a clinical trial utilizing new, innovative therapies may provide the most promising treatment. Circumstances unique to each patient’s situation may influence how these general treatment principles are applied and whether the patient decides to receive treatment. The potential benefits of multi-modality care, participation in a clinical trial, or standard treatment must be carefully balanced with the potential risks. The information on this website is intended to help educate patients about their treatment options and to facilitate a mutual or shared decision-making process with their treating cancer physician.
Surgery
Conventional surgery for colon cancer requires surgeons to create a large opening in the abdomen in order to reach the cancer. This procedure involves the removal of the cancer, along with some of the normal bowel and lymph nodes that were surrounding the cancer. After this removal, the two cut ends of the colon are sewn together. In some instances, a temporary colostomy is created and the two ends of the colon are reconnected at a later time. A colostomy is an opening where the large intestine is attached to the abdominal wall and allows passage of stool into a replaceable bag outside of the patient’s body. In some instances, when the cancer cannot be completely removed, the two ends are not re-sewn together and the patient has a permanent colostomy.
Adjuvant Chemotherapy
The delivery of cancer treatment following local treatment with surgery is referred to as “adjuvant” therapy and may include chemotherapy, radiation therapy, and/or targeted therapy. Adjuvant chemotherapy is administered to patients with Stage III colon cancer for the purpose of reducing the risk of cancer recurrence.
ONCOTYPE DX
A newer test that may help guide the management of Stage III colon cancer is the Oncotype DX colon cancer test. This test—which is similar to a test that is commonly used for patients with early-stage breast cancer—is performed after surgery but before final decisions are made about adjuvant (post-surgery) therapy. The test estimates the risk of cancer recurrence by evaluating the activity of certain genes in a sample of tumor tissue. Risk of recurrence can vary among patients with Stage III colon cancer, and use of the Oncotype DX test in combination with other markers of risk may help to individualize treatment decisions.
Treatment of the Elderly
A large percentage of patients with colon cancer are 65 years or older. Sometimes elderly patients and/or their physicians may believe that believe that treatment will be more toxic for elderly patients than it is for their younger counterparts. Due to this perceived intolerability of therapy, elderly patients often do not receive optimal treatment.[1] Many older patients are able to tolerate standard treatment, however, and receipt of standard treatment improves cancer outcomes. Elderly patients with colon cancer eligible for adjuvant therapy should speak with their physician regarding their individual risks and benefits of adjuvant therapy.
Strategies to Improve Treatment
The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. Future progress in the treatment of Stage III colon cancer will result from the continued evaluation of new treatments in clinical trials. Participation in a clinical trial may offer patients access to better treatments and advance the existing knowledge about treatment of this cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. Areas of active exploration to improve the treatment of Stage III colon cancer include the following:
New Adjuvant Chemotherapy Regimens: Several new chemotherapy drugs show promising activity for the treatment of advanced or recurrent rectal cancer. Development of new multi-drug chemotherapy treatment regimens that incorporate new or additional anti-cancer therapies for use as neoadjuvant and/or adjuvant treatment is an active area of clinical research.
Laparoscopic surgery: Laparoscopic surgery is used for many types of surgery with the short-term advantages of less pain, fewer wound complications, quicker post-operative recovery, and shorter hospital stays. Instead of making one long incision in the abdomen, the surgeon makes several smaller incisions. Special long instruments are inserted through these incisions to remove part of the rectum and lymph nodes. One of the instruments has a small video camera on the end, which allows the surgeon to see inside the abdomen. Once the diseased part of the rectum has been freed, one of the incisions is made larger to allow for its removal.
Laparoscopic-assisted surgery appears to be about as likely to be curative as the standard approach for earlier-stage cancers.[2] However, there is still limited information from randomized trials about the approach. In addition, laparoscopic surgery requires special expertise and patients need to be treated by a skilled surgeon who has done a lot of these operations.
Targeted Therapies: Targeted therapies are anticancer drugs that interfere with specific pathways involved in cancer cell growth or survival. Some targeted therapies block growth signals from reaching cancer cells; others reduce the blood supply to cancer cells; and still others stimulate the immune system to recognize and attack the cancer cell. Depending on the specific “target”, targeted therapies may slow cancer cell growth or increase cancer cell death. Targeted therapies may be used in combination with other cancer treatments such as conventional chemotherapy. Targeted therapies that have shown a benefit for selected patients with advanced colon cancer include Avastin® (bevacizumab), Erbitux® (cetuximab), and Vectibix® (panitumumab).
Managing Side Effects: Techniques designed to prevent or control the side effects of cancer and its treatments are called supportive care. Side effects not only cause patients discomfort, but also may prevent the delivery of therapy at its planned dose and schedule. In order to achieve optimal outcomes from treatment and improve quality of life, it is imperative that treatment is delivered as planned and that side effects resulting from cancer and its treatment are appropriately managed. For more information, go to Managing Side Effects.
References
[1] Kahn KL, Adams JL, Weeks JC, et al. Adjuvant chemotherapy use and adverse events among older patients with stage III colon cancer. Journal of the American Medical Association .2010;303:1037-1045.
[2] Jayne DG, Thorpe HC, Copeland J et al. Five-year follow-up of the Medical Research Council CLASICC trial of laparoscopically assisted versus open surgery for colorectal cancer. British Journal of Surgery. 2010;97:1638-45.
Following surgical removal of colon cancer, the cancer is referred to as Stage II if the final pathology report shows that the cancer has penetrated the wall of the colon into the abdominal cavity, but does not invade any of the local lymph nodes and cannot be detected in other locations in the body.
Stage II adenocarcinoma of the colon is a common and frequently curable cancer. Depending on features of the cancer, 60-75% of patients are cured without evidence of cancer recurrence following treatment with surgery alone. Stage II cancer can be further divided into three stages: IIA, IIB, and IIC. In Stage IIA, the tumor has grown through the outermost layers of the colon into tissues surrounding the colon. In Stages IIB and IIC, the involvement of other tissues and organs is more extensive. Stage II colon cancer does not, however, involve the lymph nodes or distant parts of the body.
Despite undergoing complete surgical removal of the cancer, 25-40% of patients with Stage II colon carcinoma experience recurrence of their cancer. Typically, cancer recurs because there are small amounts of cancer that had spread outside the colon and were not removed by surgery. These cancer cells cannot be detected with any of the currently available tests. Undetectable areas of cancer outside the colon are referred to as micrometastases. The presence of micrometastases causes the relapses that follow surgical treatment. An effective treatment is needed to eliminate micrometastases and improve cure rates of Stage II cancer. Efforts are currently underway to find such a therapy.
The following is a general overview of treatment for Stage II colon cancer. Treatment may consist of surgery, radiation, chemotherapy and/or targeted therapy (drugs which act by a different mechanism than chemotherapy to target tumor cells). Multi-modality treatment, which is treatment using two or more techniques, is increasingly recognized as an important approach for increasing a patient’s chance of cure or prolonging survival. In some cases, participation in a clinical trial utilizing new, innovative therapies may provide the most promising treatment. Circumstances unique to each patient’s situation may influence how these general treatment principles are applied and whether the patient decides to receive treatment. The potential benefits of multi-modality care, participation in a clinical trial, or standard treatment must be carefully balanced with the potential risks. The information on this website is intended to help educate patients about their treatment options and to facilitate a mutual or shared decision-making process with their treating cancer physician.
Surgery
Conventional surgery for colon cancer requires surgeons to create a large opening in the abdomen in order to reach the cancer. This procedure involves the removal of the cancer, along with some of the normal bowel and lymph nodes that were surrounding the cancer. After this removal, the two cut ends of the colon are sewn together. In some instances, a temporary colostomy is created and the two ends of the colon are reconnected at a later time. A colostomy is an opening where the large intestine is attached to the abdominal wall and allows passage of stool into a replaceable bag outside of the patient’s body. In some instances, when the cancer cannot be completely removed, the two ends are not re-sewn together and the patient has a permanent colostomy.
Adjuvant Chemotherapy
The delivery of cancer treatment following local treatment with surgery is referred to as “adjuvant” therapy and may include chemotherapy, radiation therapy, and/or targeted therapy. Adjuvant chemotherapy improves outcomes among patients with Stage III colon cancer, but the benefits among patients with Stage II colon cancer are less clear. A review of previously published clinical trials reported that adjuvant chemotherapy may improve disease-free survival, but does not appear to improve overall survival, among patients with Stage II colon cancer.1 Routine use of adjuvant chemotherapy is not recommended for patients with Stage II colon cancer, but it may be considered for some patients, particularly those whose cancers have high-risk features.2 Risk of cancer recurrence can be estimated based on the specific characteristics of the cancer, as well as by genomic tests such as Oncotype DX.3
ONCOTYPE DX
A newer test that may help guide treatment decisions for patients with Stage II colon cancer is the Oncotype DX colon cancer test. This test—which is similar to a test that is commonly used for patients with early-stage breast cancer—is performed after surgery but before final decisions are made about adjuvant (post-surgery) therapy. The test estimates the risk of cancer recurrence by evaluating the activity of certain genes in a sample of tumor tissue. Risk of recurrence can vary greatly among patients with Stage II colon cancer, and use of the Oncotype DX test in combination with other markers of risk may help to individualize treatment decisions.
Treatment of the Elderly
A large percentage of patients with colon cancer are 65 years or older. Sometimes elderly patients and/or their physicians may believe that believe that treatment will be more toxic for elderly patients than it is for their younger counterparts. Due to this perceived intolerability of therapy, elderly patients often do not receive optimal treatment.4 Many older patients are able to tolerate standard treatment, however, and receipt of standard treatment improves cancer outcomes. Elderly patients with colon cancer eligible for adjuvant therapy should speak with their physician regarding their individual risks and benefits of adjuvant therapy.
Strategies to Improve Treatment
The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. Future progress in the treatment of Stage II colon cancer will result from the continued evaluation of new treatments in clinical trials. Participation in a clinical trial may offer patients access to better treatments and advance the existing knowledge about treatment of this cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. Areas of active exploration to improve the treatment of Stage II colon cancer include the following:
New Adjuvant Chemotherapy Regimens: Several new chemotherapy drugs show promising activity for the treatment of advanced or recurrent rectal cancer. Development of new multi-drug chemotherapy treatment regimens that incorporate new or additional anti-cancer therapies for use as neoadjuvant and/or adjuvant treatment is an active area of clinical research.
Laparoscopic surgery: Laparoscopic surgery is used for many types of surgery with the short-term advantages of less pain, fewer wound complications, quicker post-operative recovery, and shorter hospital stays. Instead of making one long incision in the abdomen, the surgeon makes several smaller incisions. Special long instruments are inserted through these incisions to remove part of the rectum and lymph nodes. One of the instruments has a small video camera on the end, which allows the surgeon to see inside the abdomen. Once the diseased part of the rectum has been freed, one of the incisions is made larger to allow for its removal.
Laparoscopic-assisted surgery appears to be about as likely to be curative as the standard approach for earlier-stage cancers.5 However, there is still limited information from randomized trials about the approach. In addition, laparoscopic surgery requires special expertise and patients need to be treated by a skilled surgeon who has done a lot of these operations.
Targeted Therapies: Targeted therapies are anticancer drugs that interfere with specific pathways involved in cancer cell growth or survival. Some targeted therapies block growth signals from reaching cancer cells; others reduce the blood supply to cancer cells; and still others stimulate the immune system to recognize and attack the cancer cell. Depending on the specific “target”, targeted therapies may slow cancer cell growth or increase cancer cell death. Targeted therapies may be used in combination with other cancer treatments such as conventional chemotherapy. Targeted therapies that have shown a benefit for selected patients with advanced colon cancer include Avastin® (bevacizumab), Erbitux® (cetuximab), and Vectibix® (panitumumab).
Managing Side Effects: Techniques designed to prevent or control the side effects of cancer and its treatments are called supportive care. Side effects not only cause patients discomfort, but also may prevent the delivery of therapy at its planned dose and schedule. In order to achieve optimal outcomes from treatment and improve quality of life, it is imperative that treatment is delivered as planned and that side effects resulting from cancer and its treatment are appropriately managed. For more information, go to Managing Side Effects.
References
1 Figuerdo A, Coombes ME, Mukherjee S. Adjuvant therapy for completely resected stage II colon cancer. Cochrane Database of Systematic Reviews. 2008;(3):CD005390.
2 Benson AB, Schrag D, Somerfield MR. American Society of Clinical Oncology recommendations on adjuvant chemotherapy for stage II colon cancer. Journal of Clinical Oncology. 2004;15:3408-19.
3 Gray RG, Quirke P, Handley K et al. Validation study of a quantitative multigene reverse transcriptase-polymerase chain reaction assay for assessment of recurrence risk in patients with stage II colon cancer. Journal of Clinical Oncology. Early online publication November 7, 2011
4 Kahn KL, Adams JL, Weeks JC, et al. Adjuvant chemotherapy use and adverse events among older patients with stage III colon cancer. Journal of the American Medical Association .2010;303:1037-1045.
5 Jayne DG, Thorpe HC, Copeland J et al. Five-year follow-up of the Medical Research Council CLASICC trial of laparoscopically assisted versus open surgery for colorectal cancer. British Journal of Surgery. 2010;97:1638-45.
Following colon cancer surgery, the cancer is classified as a Stage I colon cancer if the final pathology report shows that the cancer is confined to the lining of the colon. Stage I cancer does not penetrate the wall of the colon into the abdominal cavity, has not spread to any adjacent organs or local lymph nodes and cannot be detected in other locations in the body.
Depending on features of the cancer under the microscope, Stage I colon cancer survival rates are high: approximately 90% of patients are cured with colorectal surgery alone and will not have evidence of cancer recurrence.
Despite undergoing surgical removal of the cancer, a minority of patients with Stage I colon cancer may experience recurrence of their cancer. It is important to realize that a few patients with Stage I disease already have small amounts of cancer that have spread outside the colon and were not removed by surgery. These cancer cells cannot be detected with any of the currently available tests. Undetectable areas of cancer outside the colon are referred to as micrometastases. The presence of micrometastases causes the relapses that follow treatment with surgery alone. An effective treatment is needed to eliminate micrometastases in order to improve the cure rate achieved with surgical removal of the cancer. Efforts are currently underway to find such a therapy.
The following is a general overview of treatment for Stage I colon cancer. Treatment may consist of surgery with or without adjuvant (post-surgery) treatment. Multi-modality treatment, which is treatment using two or more techniques, is increasingly recognized as an important approach for increasing some patients’ chance of cure or prolonging survival. In some cases, participation in a clinical trial utilizing new, innovative therapies may provide the most promising treatment. Circumstances unique to each patient’s situation may influence how these general treatment principles are applied and whether the patient decides to receive treatment. The potential benefits of multi-modality care, participation in a clinical trial, or standard treatment must be carefully balanced with the potential risks. The information on this Web site is intended to help educate patients about their treatment options and to facilitate a mutual or shared decision-making process with their treating cancer physician.
SURGERY
Surgery to remove the cancer is the primary treatment for Stage I colon cancer. In some cases, it’s possible to completely remove a cancerous colon polyp during colonoscopy. In other cases, colon cancer surgery may involve open surgery (which involves a single large incision) or laparoscopic surgery (which involves several small incisions).
ADJUVANT THERAPY
The delivery of cancer treatment following local treatment with surgery is referred to as “adjuvant” therapy and may include chemotherapy, radiation therapy and/or targeted therapy. Adjuvant chemotherapy is commonly used for patients with Stage III colon cancer and may also be used in selected patients with Stage II colon cancer. The goal of chemotherapy in these patients is to reduce the risk of cancer recurrence. Thus far, clinical trials have not been performed evaluating adjuvant treatment in patients with Stage I cancers because of the very high cure rate achieved with surgery alone.
STRATEGIES TO IMPROVE TREATMENT
The development of more effective cancer treatments requires that new and innovative therapies be evaluated with cancer patients. Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. Future progress in the treatment of Stage I colon cancer will result from the continued evaluation of new treatments in clinical trials. Participation in a clinical trial may offer patients access to better treatments and advance the existing knowledge about treatment of this cancer. Patients who are interested in participating in a clinical trial should discuss the risks and benefits of clinical trials with their physician. Areas of active exploration to improve the treatment of Stage I colon cancer include the following:
Improvement in Predicting Need for Adjuvant Therapy: Undetectable areas of cancer outside the colon are referred to as micrometastases. The presence of micrometastases may cause the cancer to relapse following treatment with surgery alone, but physicians currently cannot predict which patients will relapse.
Adjuvant chemotherapy has been shown to decrease the risk of cancer recurrence in patients with Stage III colon cancer, but benefits in patients with Stage I cancer — who have a high rate of cure with surgery alone — have not been demonstrated. New methods of determining which patients with early-stage colon cancer are at highest risk of cancer recurrence may identify a subset of patients who could potentially benefit from adjuvant treatment. A test that is being used for some patients with Stage II colon cancer is the Oncotype DX colon cancer test. The test estimates the risk of cancer recurrence by evaluating the activity of certain genes in a sample of tumor tissue.
