What’s new in colorectal cancer research?
Research is always going on in the area of colorectal cancer. Scientists are looking for causes and ways to prevent colorectal cancer, better ways to find it early, and ways to improve treatments. Here are some examples of current research.
Reducing colorectal cancer risk
Many studies are looking to identify the causes of colorectal cancer, in the hopes of using this knowledge to help prevent it.
Other studies are looking to see if certain types of diets, dietary supplements, or medicines can lower a person’s risk of colorectal cancer. For example, many studies have shown that aspirin and similar pain relievers might help lower the risk of colorectal cancer, but these drugs can sometimes have serious side effects. Researchers are now trying to determine if there are some groups of people for whom the benefits would outweigh the risks.
Early detection tests
Doctors are looking for better ways to find colorectal cancer early by studying new types of screening tests and improving the ones already being used.
Lab tests to help predict cancer recurrence risk
Lab tests (including Oncotype Dx® Colon Cancer Assay, ColoPrint®, and ColDx™) have been developed to help predict which patients have a higher risk of their colorectal cancer coming back after treatment. The tests do this by looking at the activity of many different genes inside colorectal cancer cells. So far, though, none of these tests have been shown to help predict which people could benefit from chemo or other treatments.
Tests to help stage colorectal cancer
Researchers have developed a test that can find areas of colon cancer spread in nearby lymph nodes that wouldn’t have been found with the tests normally used. This test detects a kind of RNA that is in some colon cancer cells but not in normal lymph node cells. This may help identify patients who have a higher stage of colon cancer than originally suspected, and who might benefit from chemotherapy after surgery.
Researchers are constantly looking for better ways to treat colorectal cancer.
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 and rectal cancers. This approach usually lets patients recover faster, with less pain after the operation, and it seems to be about 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 to see if it as effective as standard surgery.
Chemotherapy is an important part of treatment for many people with colorectal cancer, and doctors are constantly trying to make it more effective and safer. Different approaches are being tested in clinical trials, including:
- Testing new chemo drugs (such as trifluridine and tipiracil) or drugs that are already used against other cancers (such as cisplatin or gemcitabine).
- Looking for new ways to combine drugs already known to be active against colorectal cancer, such as irinotecan and oxaliplatin, to improve their effectiveness.
- Studying the best ways to combine chemotherapy with radiation therapy, targeted therapies, and/or immunotherapy.
Targeted therapy drugs work differently from standard chemotherapy drugs. They affect specific parts of cancer cells that make them different from normal cells. Several targeted therapy drugs are already used to treat colorectal cancer. Doctors continue to study the best way to give these drugs to make them more effective, as well as looking at new targeted therapy drugs.
Targeted therapies are currently used to treat advanced colorectal 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.
An exciting area of research is the field of immunotherapy, which is treatment that uses the body’s own immune system to fight the cancer.
Immune checkpoint inhibitors: An important part of the immune system is its ability to keep itself from attacking normal cells in the body. To do this, it uses “checkpoints” – molecules on immune cells that need to be turned on (or off) to start an immune response. Cancer cells sometimes use these checkpoints to avoid being attacked by the immune system.
Newer drugs that target checkpoint molecules such as PD-1 hold a lot of promise as cancer treatments. Unfortunately, early studies of some of these drugs against colorectal cancer did not result in many responses to treatment. However, colorectal cancers that have gene changes known as microsatellite instability (MSI) have been found to be more likely to respond to the anti-PD-1 drug pembrolizumab (Keytruda). A large study is now under way to try to confirm this finding.
Cancer vaccines: 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 person’s immune reaction to fight colorectal cancer more effectively.
Many types of vaccines are being studied. For example, some vaccines are created by removing some of the person’s own immune system cells (called dendritic cells) from their blood, exposing them in the lab to a substance that will make them attack cancer cells, and then putting them back into the person’s body. At this time, these types of vaccines are only available in clinical trials.
Last Medical Review: 10/15/2015
Last Revised: 01/20/2016