4 Things to Consider When Deciding on Colorectal Cancer Treatment
Following a colorectal cancer diagnosis, there are several decisions that will need to be made, including the sort of cancer treatment to receive.
However, given how heterogeneous colorectal cancer is, some treatment methods may be more effective than others, depending on how the disease has developed. In the case where there are many options available to you, how do you know which treatment is the best for you?
1. Treatment doesn’t occur just once
The complexity of colorectal cancer means that treatment is often not a one-and-done process. Extensive treatment often needs to be done in steps, with different treatments used in combination.
As part of some treatment plans, surgery to remove the colonic tumors may be recommended as primary treatment.
However, in the case of large tumors, chemotherapy drugs may be administered as neoadjuvant treatment, or treatment before surgery, to help reduce the size of the tumors.
After surgery is completed, further chemotherapy or other treatments, referred to as adjuvant treatment may be given to completely remove all cancerous cells and tissue.
In the case of this patient, the metastatic cancer also needs to be treated. The first-line treatment offered for cancer that has metastasized to the liver may include hepatic artery infusion, where chemotherapy drugs are injected directly into the hepatic artery leading to the liver.
Should the first-line treatment be unsuccessful, second-line treatment for metastatic cancer is then administered.
2. Treatment depends on the cancer stage
As part of your diagnosis, your doctor would also have explained to you what stage your cancer is at.
Cancer stages provide an indication of how severe the cancer is, including how much it has spread and if it has affected other organs. Cancer localized in the colon may only require surgery to remove the affected area, and may not always require adjuvant chemotherapy.
Late-stage cancers that have spread to the lymph nodes and other organs often require surgery along with other treatments to effectively eliminate the cancer.
In the case of rectal cancer, preoperative radiation therapy may be required to shrink the tumor, though this depends on the T and N grading of the tumor.
3. The molecular details matter
Broadly speaking, the colorectal cancer treatments that are usually recommended at first pass may seem the same for most patients. However, what makes every cancer survivor’s journey unique is how effective different treatments may be.
Biomarkers play a key role in determining the right type of treatment for each patient. They can be used as predictive factors — these are used to measure the level of response, or lack of, in response to a particular therapy. For instance, molecular predictive factors are useful in determining if stage 2 colorectal cancer patients should undergo adjuvant chemotherapy. Typically, chemotherapy is not recommended for stage 2 patients, but its inclusion can be determined based on the following patient subgroups.
Stage 2 colorectal cancer subgroups | Inclusion of adjuvant chemotherapy in treatment |
---|---|
Patients with T4 tumors that have higher risk of recurrence | Should be included in treatment |
Patients with other high-risk factors, including:
| May be included in treatment |
Patients with mismatch repair deficiency/microsatellite instability tumors | Should not be offered adjuvant chemotherapy |
Source: Baxter et al., 2022
Appropriate treatment may also be determined through molecular profiling. The National Cancer Institute defines molecular profiling as a way to “check for certain changes in a gene or chromosome that may increase a person’s risk of developing cancer or other diseases”. This is done using samples of tissue, blood or other bodily fluids to check for different biomarkers, such as genes, proteins or other molecules that may be indicative of disease.
For colorectal cancer, molecular profiling is usually recommended for all metastatic cancer patients. These patients’ profiles are usually examined for mutations in the Ras or Raf genes, along with the MMR/MSI and HER2 (human epidermal growth factor receptor 2) status to design a treatment plan.
4. Treatment intensity depends on performance status
Besides the type of treatment, another aspect of treatment that requires consideration is the intensity. This may come in the form of varied doses of chemotherapy drugs, or the use of surgery to remove cancerous tissue.
The key determinant of the appropriate treatment intensity is a patient’s performance status. Performance status is a means to measure the impact of a disease on a patient’s daily living ability or functional impairment, and is used as a means to compare the effectiveness of different treatments. This is particularly important for metastatic colorectal cancer patients, whose performance status and molecular profiling have to be taken into consideration to determine their eligibility for more intensive chemotherapy regimens, or metastasectomy.
Should you also consider clinical trials?
When it comes to clinical trials, it’s important to bear in mind that these trials are research studies aimed at improving treatment or finding new ways to treat cancer where conventional methods fail. Clinical trials are conducted following strict guidelines and new drugs and treatments go through many years of trial before they receive FDA approval.
Enrolling in clinical trials is completely voluntary, and patients can withdraw from the trial at any stage. However, it’s important to be fully aware of the risks and make an informed decision before enrolling.
On average, about one in five drugs that enter clinical trials receive FDA approval, but like with many existing cancer drugs, there may be severe side effects to drugs that are in clinical trials. Sometimes, newer is not always better, either. A clinical trial drug may not be as effective as an existing treatment, and there is no guarantee of successful treatment.
Ultimately, participating in a clinical trial benefits more than just the patient. Especially where conventional treatments are ineffective, trials not only give hope to the patient, but also moves science forward and enables the discovery and development of newer and better cancer treatments for future generations.