Exciting Advances in Colon Cancer Treatments
Colorectal cancer, including bowel cancer and rectal cancer, is a type of cancer involving the lower intestinal tract. It begins with a growth or polyp on the inner wall of the colon and progresses to cancer as time goes on. In 2014, there were an estimated 370,000 new colorectal cancer cases in China. It is the third most common cancer among women and the fourth most common cancer among men in China (Global Health Journal, 2018).
The treatment plan for colon cancer depends on a variety of factors. For stage 0 and 1 cases, the cancer has not spread outside into nearby tissue or lymph nodes; therefore, surgery is the standard treatment. With more advanced disease, chemotherapy, radiation, immunotherapy, surgery, local therapies, or targeted therapy may be needed based on the patient’s health status and stage. (American Cancer Society, 2020)
Immunotherapy, as its name implies, works by using the patient’s immune system to fight cancer. Unlike traditional chemotherapy and radiation therapy where healthy cells are killed alongside cancerous cells, immunotherapy tries to aim specifically at the cancer cells like a guided missile. As this therapy attempts to spare the healthy, rapid growing cells, immunotherapy has the advantage of fewer unwanted side effects such as hair loss (Nature Review, 2019).
There are currently three immunotherapy medications on the market for colorectal cancer, Keytruda® (pembrolizumab), Opdivo®(nivolumab), and Yervoy®(ipilimumab). Keytruda® and Opdivo® target a protein called PD-1 on the immune system cells, T cells. PD-1 acts as a lock on the T cell. Once the lock on T cells gets locked by the “key” protein PD-L1 located on the cancer cell, the cancer cell can escape from being killed by T cells. Keytruda® and Opidivo® act as shield protections to protect the lock on the T cells. In this case, T cells will not be locked by cancer cells and can kill the cancer cells more easily (Nature Review, 2019).
Yervoy® is the newest immunotherapy approved by the FDA for colorectal cancer in 2018. In patients with microsatellite instability-high or mismatch repair deficient cancers, it is used along with Opdivo® (National Cancer Institute, 2018). Unlike Keytruda® and Opdivo® which block the protein PD-1, Yervoy® works by blocking a different protein, CTLA-4. CTLA-4 protein acts as an additional “off” switch on T cells to keep T cells from killing cancer cells. By blocking the “off” switch CTLA-4, Yervoy® boosts a patient's immune response to the cancer cells (Nature Review, 2019).
There are a number of clinical trials focused on colon cancer that utilize a variety of different treatment methods, such as monospecific and bispecific antibodies, cellular therapies, and vaccines (Nature Review, 2019). At RangeLight Health, we understand that it can be overwhelming to understand the relative nuances and intricacies of new colon cancer treatments. We are here to help you manage this process. Contact RangeLight Health today to speak with a top U.S.-based oncologist and learn more about new colon cancer treatment options.