The Many Different Types Of Chemotherapy

There are many different types of chemotherapy. They are selected based on the type of cancer to be treated and the patient’s condition. In this article, we explain the most common forms and the pharmacological substances used in chemotherapy.

Chemotherapy is, as you probably know,  one of the most common treatments for cancer. It covers a wide range of medications, which means that there are many different types of chemotherapy.

The goal of this treatment is to destroy the cancer cells, to cure the disease. However, all forms of chemotherapy affect both the cancer cells and the healthy cells, so the treatment can have serious side effects.

Throughout this article, we will explain the different types of chemotherapy that are available and their main characteristics.

Alkylating agents

Alkylating agents reach their highest level of activity during the relaxation phase, and are not linked to cell cycles. Thus, the healthcare professional can prescribe different forms of treatment with chemotherapy:

• First, mustard gas derivatives. For example, cyclophosphamide.
• Hexamethylmelamine.
• Hydrazines and triazines. Altretamine and procarbazine, among others.
• Certain nitroso compounds. They are unique because, unlike most other chemotherapies, they can cross the blood-brain barrier, which is the membrane that protects the brain. Therefore, they are effective in the treatment of brain tumors.
• And as a last resort, metal salts.

Plant alkaloids

This is a form of chemotherapy that comes from specific plants. For example, vinca alkaloids come from the plant  Catharantus rosea. This group also includes taxanes, which are made from the bark of California yew trees.

All drugs with plant alkaloids used in chemotherapy are, unlike the previous group, linked to cell cycles. That is, they attack the cells, depending on the phase of their division they are in. In addition to vinca alkaloids and taxanes, podophyllotoxins and camptothecin belong to this group.

The doctor recommends what kind of chemotherapy to use, with the patient’s consent.

Types of chemotherapy also include antibiotics for tumors

This is another form of chemotherapy that is based on natural substances. Instead of coming from plants, this chemotherapy comes from a species of the soil fungus, streptomyces.

Antibiotics against tumors exert their effect on cancer cells at different stages of the cell cycle, and not at a specific time, as the above types. Here are some of the most commonly used forms:

• Anthracyclines. such as duxorubicin or epirubicin. These drugs have long-term cardiotoxic effects.

• Dactinomycin.
• Mitomycin.
• Bleomycin.

Antimetabolites

This is a form of chemotherapy that is very similar to the natural molecules found in cells. block cell division

Antimetabolites are classified according to the substances they interact with:

• Folic acid antagonists. Methotrexate.
• Pyrimidine antagonists. 5-fluorouracil or capecitabine.
• Purine antagonists. 6-mercaptopurine.
• Adenosine deaminase inhibitors. Cladribine, fludarabine, nelarabine and pentostatin.

Topoisomerase inhibitors are also among types of chemotherapy

These are substances that have their effect via their ability to disrupt the activity of topoisomerase enzymes (both I and II). These enzymes are responsible for manipulating the DNA structure needed for replication. Two examples of these drugs are irinotecan and etoposide.

Various antineoplastic agents

As the name of this group suggests, it consists of drugs for chemotherapy  that do not belong to one of the other groups because they are unique. It could be:

• Mitotan
• Asparagine and pegaspargase
• Estramustin
• Retinoids

Conclusion on the different types of chemotherapy

In addition to chemotherapy,  there are many other types of chemical therapy for cancer,  such as custom molecular therapy, immunotherapy, and hormone therapy. All of these therapies have enabled great advances in the treatment of cancer.

But we still face a very big challenge, and more research is needed in this therapeutic field. The ultimate goal is therefore to achieve highly specialized types of chemotherapy that only attack cancer cells.