Immunotherapy vs Chemotherapy: What's the Difference?

With the continuous progress in medicine and healthcare, cancer treatment is increasingly becoming more affordable and readily available to many patients. Many already know about chemotherapy, which uses specialised drugs that directly eliminate cancer cells.


However, there have also been other breakthroughs in treating cancer, and one such solution is immunotherapy. It is only natural for those new to this type of treatment to be curious about its differences from chemotherapy, effectiveness, and which is the more suitable choice among the two. To answer these questions, we shall discuss the specifics of each treatment and the differences in which they work.


An overview of immunotherapy and chemotherapy Cancer immunotherapy is a treatment that bolsters a patient's immune system and makes it more effective at fighting cancer. It works to harness and enhance the immune system's innate power to work more effectively against the disease by boosting aspects such as enabling it to recognise, target, and destroy cancer cells throughout the body better.


Immunotherapy can either be administered alone or in combination with other cancer treatments. It has proven itself to be an effective solution for patients experiencing various types of cancers, making it a promising and new approach to treating cancer since the development of the first chemotherapies back in the 1940s.


On the other hand, chemotherapy, also called "chemo" for short, is a cancer treatment that utilises drugs to eliminate cancer cells directly. It targets rapidly-dividing cells within a patient's body, effectively removing fast-growing tumours. Chemotherapy can be used by itself or combined with radiation therapy, surgery, and immunotherapy. The differences between the two treatments How they work The main difference between immunotherapy and chemotherapy is their method of combating cancer. Immunotherapy does not outright eliminate cancer cells as chemotherapy does; it only helps boost a patient's immune system and its ability to respond to, identify, and destroy cancer cells. The side effects Due to its primary purpose of eliminating cancerous tumours, chemotherapy works to attack and destroy all rapidly dividing cells in the body, regardless of whether it’s cancerous or not. This means that cells in hair follicles and those in the lining of the gut tend to be affected as well, resulting in the treatment's well-known side effects like nausea and hair loss.


Meanwhile, immunotherapy's possible side effects generally result from a misdirected or overstimulated immune response, ranging from anywhere between mild and severe.


To mitigate the hair loss caused by chemotherapy, ICS provides cold caps, which consist of a tightly fitted hat that resemble a helmet. Usually, it will be filled with a cold gel or liquid.


The cold caps narrow the blood vessels located below the scalp skin, decreasing the amount of chemotherapy medicine that will reach the hair follicles. Moreover, the cold temperature lowers the metabolic activity and slows the cell division.


Because less chemotherapy medicine makes it to the follicles, the hair is less likely to fall out.


Its effectiveness is proved by a study conducted in 2017, where around 59% of the female breast cancer patients lost less than half their hair during a taxane-based chemotherapy when using the cold caps.


Thanks to the cold caps, 16% the women who received scalp cooling during anthracycline chemotherapy also lost less than half their hair. Length and effectiveness of the treatment The result from both types of treatment will vary significantly from patient to patient due to the many factors involved, most of which are specific to the person and their type of cancer.


It may take a defined number of treatments to administer immunotherapy fully, or it could go on indefinitely. This all depends on the patient's responses to the treatment or whether they are receiving it due to being part of a clinical trial.


When speaking about the length of each treatment, there will be differences in how patients respond to either chemotherapy or immunotherapy in the short term. For example, chemotherapy may cause detected tumours to shrink immediately on the first session.


Usually, that is not the case with immunotherapy, wherein it may take longer for the desired effects on the immune system to take effect and get it to mobilise and attack tumours.


However, there are some cases wherein tumours may initially appear to become bigger. In truth, it may only be caused by the infiltration of immune cells. This phenomenon is not uncommon in immunotherapy treatments and is not an indication of the treatment being ineffective.


Unlike chemotherapy, immunotherapy persists and can provide long-term protection even when the treatment expires. This is due to a patient's immune system recognising and remembering the cancer cells they are supposed to eliminate, which is commonly known as immune memory.


This "memory" is what enables longer-lasting remissions. Clinical studies reveal that the beneficial responses from immunotherapy treatments can be durable and maintained long after the treatment ends.


In addition, some evidence even suggests that specific doses and types of chemotherapy can further enhance the immune system's responses against tumours, providing more reasons to combine immunotherapy with other treatments in certain situations. Applicable cancer types Chemotherapy alone works for many types of cancers, but not all of them. In some cases, it will need to be combined with other types of treatment. However, that is not the case for immunotherapy, which only helps boost the immune system and does not actively kill cancer cells.


Immunotherapy treatments have already resulted in significant advances in treating many types of cancers and have received approval to be the first line of treatment for various kinds of cancer. Lastly, its effectiveness is tested and proven to work even against cancers that are historically resistant to the usual chemotherapy and radiation treatments. Conclusion Despite immunotherapy being a promising solution, patients should determine what is best for their case by consulting with their doctors before anything else. Doing so will lead to the best cancer treatment path for their situation, be it chemotherapy, immunotherapy, or a combination of such treatments.


Apart from getting the right treatment plan, it is also essential to pay more attention to cancer-focused health screenings instead of just general ones. When it comes to a disease like cancer, prevention and early detection play a significant role in effective treatment.


If you are curious to know when and how to go about getting a cancer screening test, do not hesitate to reach out to us here at International Cancer Specialists. As one of the leading cancer treatment centres in Singapore, our team of specialists is always available to lend you a helping hand, whether in getting cancer screening tests or treating many types of cancer, such as breast, prostate, lung, and colon cancer.


References


McCluskey, K. (2016, June 2). Immunotherapy vs. Chemotherapy: What's the difference? Cancer Research Institute. Retrieved December 14, 2021, from https://www.cancerresearch.org/en-us/blog/june-2016/difference-cancer-immunotherapy-and-chemotherapy.


Grier, M. A. (2021, February 9). Fast facts for the frontline: Immunotherapy. Oncology Nursing News. Retrieved December 14, 2021, from https://www.oncnursingnews.com/view/immunotherapy.


Cooling caps (scalp hypothermia) to reduce hair loss. American Cancer Society. (n.d.). Retrieved January 10, 2022, from https://www.cancer.org/treatment/treatments-and-side-effects/physical-side-effects/hair-loss/cold-caps.html.

Nangia, J., Wang, T., Osborne, C., Niravath, P., Otte, K., Papish, S., Holmes, F., Abraham, J., Lacouture, M., Courtright, J., Paxman, R., Rude, M., Hilsenbeck, S., Osborne, C. K., & Rimawi, M. (2017). Effect of a scalp cooling device on alopecia in women undergoing chemotherapy for breast cancer. JAMA, 317(6), 596. https://doi.org/10.1001/jama.2016.20939