Chemotherapy: What it is & how it works.

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March 28, 2021
2 min read

Expert approval by Dr. Joe
Written by Abigail Hofmeister

When you think of cancer treatment(TREET-MINT) — Techniques to help eliminate or control a disease, the first word you think of is probably chemotherapy(KEY-MOW-THAIR-AH-PEE) — Medication used to treat cancer. We’re not surprised because chemotherapy is the term most people—including many oncologists—use to refer to any medication that treats cancer.

People use the word chemotherapy kind of like they use the word cancer. There are over 450 types of cancer, all with specific names (like breast cancer, Hodgkin Lymphoma (HL)(HODJ-KIN LIMFF-O-MAH) — An abnormal growth of infection-fighting cells (lymphocytes) that is identified by a specific cancerous cell called the Reed-Sternberg Cell, or Hepatocellular Carcinoma (HCC)(HEH-PAT-OH-CELL-YOU-LAR CAR-SI-NO-MA) — An abnormal growth that forms from hepatocytes inside the liver), but we still tend to simplify our words and say cancer.

In recent years, there has been an explosion in the number of different anticancer treatment categories; there are so many new drugs that work in new ways. Yet, many times, we simplify our words and say they all are chemotherapy.

But there’s a more strict definition of chemotherapy (and how we’ll talk about it moving forward).

Chemotherapy is a group of chemicals that doesn’t belong to a more specific class of anticancer treatment (like targeted therapy(TAR-GET-TED THAIR-AH-PEE) — Anticancer medication that attaches to a specific protein receptor and blocks the receptor’s normal function or immunotherapy(EM-MUN-O-THAIR-AH-PEE) — A biologic protein or antibody that targets a specific part of the immune system) and attempts to treat cancer by attacking common components of all cells.

Basically, since so many different types of anticancer treatment exist, all the remaining have been lumped together into the category of chemotherapy. (Chemotherapy medications also tend to be older medications).

Additionally, true chemotherapy attacks many different parts of all cells to stop the cell from growing. This is like how all cars have engines, but they may be powered by different fuel. While some medications may affect the fuel, chemotherapy attacks the engine itself or other parts that all cars have (regardless of what fuels the car).

The problem with this approach is that both normal cells and cancer cells have these same parts. So, chemotherapy can affect many cells throughout the body, including normal cells. It's not as selective about the cells it attacks.

Don’t get us wrong; chemotherapy is still an extremely important part of most cancer treatment plans as it remains highly effective at treating cancer. It’s especially important when you need to shrink or kill the cancer very fast. Unfortunately, the downside is that it can lead to more side effects than other anticancer treatment categories (like targeted therapy).

Today, it’s very common to combine chemotherapy medications with other classes of anticancer medications. These combinations, along with new medications, have been crucial in improving cancer outcomes! And, new research in these areas will continue to drive improvements. However, it’s unlikely that chemotherapy will be replaced within the foreseeable future.