What`s new in colorectal cancer research and treatment?
Research is always going on in the area of colorectal cancer. Scientists are looking for causes and ways to prevent colorectal cancer as well as ways to improve treatments.
Tests (including Oncotype Dx® Colon Cancer Assay, ColoPrint®, and ColDx™) have been developed that look at the activity of many different genes in colon cancer tumors. These tests can be used to help predict which patients have a higher risk that that the cancer will spread. So far, though, none of them have been shown to help predict who could benefit from chemo or other treatments.
Chemoprevention uses natural or man-made chemicals to lower a person's risk of developing cancer. Researchers are testing whether certain supplements, minerals (such as calcium), and vitamins (such as folic acid or vitamin D) can lower colorectal cancer risk.
Some studies have found that people who take multi-vitamins containing folic acid (also known as folate), vitamin D supplements, or calcium (through either diet or supplements) may have a lower colorectal cancer risk than people who do not. Research to clarify the possible benefits of these and other substances, such as selenium and curcumin, is now under way.
Many people take drugs known as statins to lower their cholesterol levels. These drugs may also help lower the risk of polyps and colorectal cancer. A study currently going on is looking to see if giving rosuvastatin (Crestor®) to people who had a polyp or early colon cancer will lower the risk of a new colon cancer or polyp or lower the risk of the cancer coming back.
Colorectal cancer is much easier to treat effectively if it is found at a very early stage. Studies continue to look at the effectiveness of current colorectal cancer screening methods and assess new ways to tell the public about the importance of being screened.
Only about half of Americans age 50 or older are up to date with colorectal cancer screening. If everyone were tested as recommended, thousands of lives could be saved each year. The American Cancer Society and other public health organizations are working to increase awareness of colorectal cancer screening among the general public and health care professionals.
Meanwhile, new imaging and lab tests are also being developed and tested. Newer, more accurate ways to look for changes in the stool that might indicate colorectal cancer have been developed. These include tests that are better able to detect blood in the stool (fecal immunochemical tests) and test that can detect changes in the DNA of cells in the stool.
CT colonography (also known as virtual colonoscopy) is a special type of CT scan that can find many colorectal polyps and cancers early. Most often this test is only done after the colon is cleaned out with a large amount of liquid laxative. One study, though, found that it could be helpful in screening even without this kind of prep.
These tests are described in more detail in the section “Can colorectal polyps and cancer be found early?”
Newer surgery techniques
Surgeons are continuing to improve their techniques for operating on colorectal cancers. They now have a better understanding of what makes colorectal surgery more likely to be successful, such as making sure enough lymph nodes are removed during the operation.
Laparoscopic surgery is done through several small incisions in the abdomen instead of one large one, and it's becoming more widely used for some colon cancers. This approach usually allows patients to recover faster, with less pain after the operation. Laparoscopic surgery is also being studied for treating some rectal cancers, but more research is needed to see if it as effective as standard surgery.
With robotic surgery, a surgeon sits at a control panel and operates very precise robotic arms to perform the surgery. This type of surgery is also being studied.
Different approaches are being tested in clinical trials, including:
- New chemo drugs or drugs that are already used against other cancers (such as cisplatin or gemcitabine).
- Chemo that does not include 5-FU for patients whose colorectal cancers show microsatellite instability (MSI). People whose cancers have this molecular feature tend to survive longer after surgery, but they may be less likely to be helped by chemotherapy combinations that include 5-fluorouracil (5-FU) given as adjuvant treatment after surgery.
- New ways to combine drugs already known to be active against colorectal cancer, such as irinotecan and oxaliplatin, to improve their effectiveness.
- The best ways to combine chemotherapy with radiation therapy, targeted therapies, and/or immunotherapy.
Several targeted therapies are already used to treat colorectal cancer, including bevacizumab (Avastin), cetuximab (Erbitux), and panitumumab (Vectibix). Doctors continue to study the best way to give these drugs to make them more effective.
Targeted therapies are currently used to treat advanced cancers, but newer studies are trying to determine if using them with chemotherapy in earlier stage cancers as part of adjuvant therapy may further reduce the risk of recurrence.
Researchers are studying several vaccines to try to treat colorectal cancer or prevent it from coming back after treatment. Unlike vaccines that prevent infectious diseases, these vaccines are meant to boost the patient's immune reaction to fight colorectal cancer more effectively.
Many types of vaccines are being studied. For example, some vaccines involve removing some of the patient's own immune system cells (called dendritic cells) from the blood, exposing them in the lab to a substance that will make them attack cancer cells, and then putting them back into the patient's body. At this time, these types of vaccines are only available in clinical trials.
Last Medical Review: 07/30/2013
Last Revised: 01/31/2014