How has treatment improved for patients with colorectal cancer in the last five years?
Over the past five years there has been significant progress in the treatment for patients that are diagnosed with colorectal cancer. First, it must be acknowledged that most patients are diagnosed with early stage or localized colorectal cancer due to effective screening, and the majority of these patients will be cured. Patients with localized colorectal cancer (stages I-III) are primarily treated with surgery and often chemotherapy, depending on stage and risk factors. There has been great progress in better understanding who is at higher and lower risk of cancer recurrence using circulating tumor DNA. This allows us to de-escalate therapy when appropriate, and pending the results of ongoing clinical trials, may allow us to escalate our chemotherapy in settings of increased risk. For patients diagnosed with metastatic colorectal cancer, we have made enormous progress on surgical techniques for removal of metastases and in our systemic / chemotherapy options. One of the reasons we have made progress in our therapeutic options for metastatic colorectal cancer is that we have a better understanding of the biology of the cancer and have been able to identify different subgroups of patients that are more likely to respond to targeted or immune based therapies. For example, patients with a condition called mismatch repair deficiency, or microsatellite instability high, we have immune checkpoint inhibitors such as pembrolizumab to use as initial therapy for metastatic colorectal cancer, which works exceptionally well. Another example is for patients with tumors that have a mutation in BRAFV600E, we use a targeted treatment of encorafenib and cetuximab, which has greatly improved outcomes for these patients with fewer toxicities. There are several other examples of targeted treatments that have been approved for colorectal cancer and there is a significant amount of ongoing research in this area.
Screenings via colonoscopies and other testing is a critical tool to catch CRC early when most treatable. How do you encourage patients to participate in regular screenings? Early signs they should be aware of?
I think it cannot be overstated that prevention is the goal and screening is the most important goal in this effort. In my role as a medical oncologist, I am primarily seeing patients after they have already been diagnosed with cancer and am in less of a position to counsel patients about screening. In clinical practice screening comes up much more frequently for primary care providers and gastroenterologists. However, there can be many different interactions with patients and families in the healthcare system and advocating for colorectal cancer screening is a job for all of us caring for patients. There are many different screening tests including colonoscopy, and home-based stool tests. Colonoscopy is a powerful tool because not only does it allow for the diagnosis of earlier stages of cancer that are more treatable and hopefully curable, but it also allows for the removal of pre-malignant polyps and thus actually has the power to prevent cancer. Ultimately which screening test to do is best decided between a patient and their provider, but the best screening test is the one you are willing to do. Given the new screening guidelines, essentially all adults 45 years and older should be screened. Patients with certain risk factors may be screened at a younger age.
Can you talk about your recently awarded K08 Grant from the NCI and what you hope to accomplish with these multiple clinical trials?
I am currently in my second year of my K08 career development award. This is a federally funded grant that allows me to pursue clinical and translational research for colorectal cancer. I am passionate about developing novel treatments for patients with advanced gastrointestinal cancers with a focus on colorectal cancer. This requires an understanding of drug development as well as the tumor microenvironment. Thus, as part of my grant, I am studying the relationship between DNA repair, DNA damage, and the immune response in colorectal cancer tumors to help develop new treatment strategies for colorectal cancer. Furthermore, part of my award is specifically centered around two clinical trials with novel DNA damaging strategies. We are presenting some of our initial data on one of these clinical trials at the upcoming EAS-AACR meeting March 15-17, 2023.
What role do clinical trials play in the advancement of treatment for colorectal cancer? Words of hope you can offer to patients?
Clinical trials play a major role in the advancement of new treatments and treatment strategies for patients diagnosed with colorectal cancer. All of the currently approved treatments are approved and understood only because the field has done numerous clinical trials over decades. Patient enrollment in clinical trials is absolutely critical to continue to make improvements in the lives of those patients diagnosed with cancer. Clinical trial enrollment can range from new anti-cancer chemotherapies, targeted therapies, and immunotherapies as well as new surgical and radiation strategies. By enrolling a patient in a clinical trial, we hope that they will do better, but it also has to be acknowledged that information gathered from clinical trials improves the lives for other patients for years to come. Please ask your medical team if a clinical trial may be right for you. I would just like to conclude by noting that we are making enormous progress in the treatment for colorectal cancer and every day there are new research discoveries and clinical trials making a difference for those affected by this disease.