Chemotherapy: functions, processes, and side effects

Gene mutations in cells make cells work abnormally and cause cancer. This disease must be addressed immediately so that it does not spread to healthy tissues and organs. One of the most common cancer treatments is chemotherapy. However, do you know what chemotherapy is like? Come on, see the following reviews.

What is chemotherapy and its benefits?

Chemotherapy is a method of treating disease using drugs. However, most people define chemotherapy (often abbreviated as chemo) as a method of treating cancer using specially formulated drugs to kill cancer cells.

Today, most of these drug-based cancer treatments are performed in hospitals or in palliative care centers. According to the American Cancer Society, the main goals of cancer treatment with chemotherapy are:

1. Cure cancer (curative)

In some cases, chemo can actually destroy and remove cancer cells from the body. At best, the cancer cells won't come back. However, not all cases are like this. Again, it comes down to how severe the cancer is and where it is located.

2. Prevent spread and relieve symptoms (palliative)

If cancer is difficult or even incurable, chemo is done to control the cancer cells from growing and spreading to become increasingly malignant. This will give the patient a greater life expectancy.

However, when cancer cells have spread to other parts of the body and have progressed to an advanced stage, chemo can be done to relieve cancer symptoms such as pain in certain areas of the body, thereby improving the patient's quality of life.

How does chemotherapy work?

Your body tissues are made up of billions of cells. Some of these cells will divide and multiply. This process of self-reproduction occurs when cells need to repair damage. When dividing, one cell will become 2 new identical cells.

In people with cancer, cells continue to divide without control and sometimes cause a lump called a malignant tumor.

When chemo therapy is being undertaken, the drugs can flow into the bloodstream. The way chemotherapy works is that each drug is tasked with attacking cancer cells, such as killing cells that are dividing or damaging the part of the cell's control center that makes them divide.

This chemo drug that can enter the blood circulation allows cancer cells in almost all parts of the body to be killed.

What is the chemotherapy process like?

The cancer treatment process is divided into two main stages. The stages of this chemotherapy process are:

Preparation process

Before starting cancer therapy, there are several preparations you need to do, such as:

• Undergo medical tests

You will need to do blood tests to check kidney and liver function, then a heart test to see how your heart is healthy. If problems are seen, chemo treatment may be postponed or chemo drug options will be adjusted accordingly.

• Do a dental check

You are obliged to have your teeth checked by a doctor for signs of infection. If you are, the infection will be treated first to reduce the risk of complications during chemo treatment.

• Ask about chemotherapy side effects and how to overcome them

Ask about chemotherapy side effects that may occur and the right treatment to overcome them. For example, if your fertility is compromised, you might consider keeping sperm or eggs for future use.

• Ensuring treatment does not interfere with activities

If you are still working, take time off as directed by your doctor. Then, make sure you have someone you can count on to accompany the treatment process until you return home.

• Make sure you are well rested and mentally prepared

The treatment process will leave your body exhausted. Therefore, make sure the previous few days you get enough rest. If necessary, visit a therapist to help mental readiness in dealing with this cancer treatment.

The process of giving chemotherapy drugs

Giving chemotherapy drugs is divided into various ways, such as:

• Infusion

Chemo drugs in the form of fluids are most often given as an intravenous drip into a vein. The intravenous drug will be inserted into your arm or chest.

• Injection

Apart from being in the form of an infusion, liquid chemo drugs can be injected into the body with a syringe.

• Oral

Chemo drugs in the form of pills or capsules can be taken directly and done at home. However, the availability of drugs is still limited and make sure the dosage and drug use rules are in accordance with the doctor's direction.

• Topical

Chemo drugs are also available in topical form which is applied directly to the skin to treat skin cancer.

• Jump to one area of ​​the body

Some drugs can be given to areas of the body, for example in the stomach (intraperitoneal), chest cavity (intrapleural), central nervous system (intrathecal), or through the urethra into the bladder (intravesikal).

• Straight to cancer cells

Chemotherapy drugs are given after surgery. For example, a wafer-shaped device filled with medicine is placed near the tumor after surgery. Over time, the device will break down and release the medicine inside.

Regardless of the way of administration, chemo drugs can work and have almost the same success rate. However, the actual success rate of treatment depends on the type of cancer, its severity, age, and your body's health status.

Many argue that chemo treatments cause pain. However, this depends on the process of giving chemo drugs that you are undergoing. If it is given by injection, you may feel a stinging pain when the needle is injected into the skin.

While the process of giving chemo drugs during surgery, you will be given anesthesia. If it causes discomfort, the doctor will usually prescribe pain medication.

List of drugs used in chemotherapy

Medicines for chemo are very diverse. Therefore, these drugs are grouped based on how they work, chemical structure, and their interactions with other drugs. The following groups and types of drugs that are usually used in chemotherapy are:

Alkylating agents

Alkylating agents prevent cells from making copies of themselves by damaging the DNA in the cells. Usually this drug is used to treat lung cancer, breast cancer, multiple myeloma, and blood cancer.

The use of this type of drug is known to increase the risk of leukemia, so the dosage is very concerned. Examples of alkylating agents for chemotherapy are:

• Altretamine
• Bendamustine
• Busulfan
• Carboplatin
• Carmustine
• Chlorambucil
• Cisplatin
• Cyclophosphamide
• Dacarbazine
• Ifosfamide
• Lomustine
• Mechlorethamine
• Melphalan
• Oxaliplatin
• Temozolomide
• Thiotepa
• Trabectedin

The type of nitrosourea drug has a special action, which is it can enter the brain area so it is used to treat brain cancer. An example of this type of chemo drug is streptozocin.

Antimetabolites

Antimetabolite drugs can interfere with DNA and RNA so that abnormal cells cannot divide. This type of chemo drug is usually used for leukemia, ovarian cancer, and colon cancer. Examples of drugs that are included in the antimetabolites group for chemotherapy are:

• Azacitidine
• 5-fluorouracil (5-FU)
• 6-mercaptopurine (6-MP)
• Capecitabine (Xeloda)
• Cladribine
• Clofarabine
• Cytarabine (Ara-C)
• Decitabine
• Floxuridine
• Fludarabine
• Gemcitabine (Gemzar)
• Hydroxyurea
• Methotrexate
• Nelarabine
• Pemetrexed (Alimta)
• Pentostatin
• Pralatrexate
• Thioguanine
• Trifluridine / tipiracil combination

Anti-tumor antibiotics

Although called an antibiotic, this drug is not used to treat bacterial infections, but instead changes the DNA in cells so they don't function abnormally. Examples of anti-tumor antibiotics are bleomycin, dactinomycin, mitomycin-C, and mitoxantrone.

In addition there are also classified as anthracyclines, which work to disrupt the enzyme in charge of copying DNA so that cells cannot divide. Examples of anthracyclines used in chemotherapy are:

• Daunorubicin
• Doxorubicin (Adriamycin)
• Liposomal Doxorubicin
• Epirubicin
• Idarubicin
• Valrubicin

Topoisomerase inhibitors

Topoisomerase inhibitors can interfere with an enzyme called topoisomerase, which helps separate DNA strands so that cells can copy them. The disruption of this enzyme makes cells unable to divide. Usually this drug is used to treat colorectal cancer or pancreatic cancer.

Examples of topoisomerase inhibitors for chemotherapy are:

• Irinotecan
• Liposomal irinotecan
• Topotecan
• Etoposide (VP-16)
• Teniposide

Mitotic inhibitors

Mitotic inhibitors can stop cells from dividing. It is usually used to treat blood cancers, such as leukemia and lymphoma. However, it can cause nerve damage so that the dose given is very limited.

Examples of mitotic inhibitor class drugs for chemotherapy are taxanes (cabazitaxel, docetaxel, nab-paclitaxel and paclitaxel) and vinca alkaloids (vinblastine, vincristine, liposomal vincristine, and vinorelbine).

What are the side effects of chemotherapy?

Just like any other medication, the use of drugs in chemo has very common side effects. But you don't need to worry because most of the side effects go away quickly and the rest can take months or years.

Short-term chemotherapy side effects

Possible short-term side effects of chemo drugs that usually go away after treatment is stopped, include:

• Fatigue that makes it difficult for cancer patients to carry out daily activities.
• Experience indigestion, such as nausea, vomiting, or constipation.
• Hair loss, even on the eyebrows, eyelashes, and body hair in the first to third week of chemo treatment.
• It is very easy to get injured, experience bleeding, and infection because the immune system decreases.
• The color of urine changes to orange, red, green, or dark yellow sometimes accompanied by a strong odor that usually disappears within 24-72 hours of treatment.
• Often have canker sores or sores around the mouth, and the tongue feels like metal.

Long-term chemotherapy side effects

These side effects can last a very long time, even if you have it for life because of the damage. Sometimes this occurs for a long time or when the patient has secondary cancer again, so he needs to undergo chemo again.

Long-term side effects of chemo that may affect cancer patients include:

• Heart and blood vessel problems

Some chemo drugs are known to weaken the heart muscle, damage blood vessels, cause heart rhythm disturbances (arrhythmias), thereby increasing the risk of heart failure and heart attack.

• Hearing problems

Many chemotherapy drugs are ototoxic (can cause hearing loss) due to damage to the cochlea, the sensory hair cells in the inner ear. As a result, this can block the sound from reaching the auditory nerve, so that the sound does not reach the brain.

• Decreased fertility

Cancer treatment can cause sex problems, such as stopping the production of sex hormones (progesterone and estrogen) and the work of the ovaries causing premature menopause, and damaging the uterus in women. Meanwhile, in men, sperm production is disturbed, the hormone testosterone decreases, and the nerves and blood vessels around the pervis make it difficult to get an erection.

• Brain disorders

Chemotherapy also causes problems in the brain, which can reduce cognitive function, acute cognitive changes (delirium, such as confusion, being quiet, disoriented, and hallucinating), and increase the risk of dementia.

Tips to relieve the side effects of chemotherapy

The side effects of chemo are very disturbing. Do not let this make you give up following chemo. The reason is, there are various tips that can help relieve side effects, such as:

• Take breaks and adjust activities accordingly

You can deal with fatigue by getting enough rest. Change your daily activities by reducing strenuous activities that make fatigue worse and take a nap.

• Follow a cancer diet

Following a cancer diet helps boost the immune system, relieve constipation, prevent anemia, and reduce the metallic taste in the mouth. Eat carefully, pay attention to portions, add lemon juice / spices to dishes, and use plastic rather than metal utensils.

• Take side effect relievers

If side effects such as nausea occur, take cancer pain relievers or anti-nausea medications your doctor prescribes.

• Use a head covering

Hair loss often leads to baldness. You can cover it with a hat, scarf, or temporary wig. Don't use hair oil or brush too often. After chemo treatment is complete, hair can grow back in a few weeks.

• Maintain cleanliness and avoid contact with sick people

Body hygiene by diligently washing hands and being careful in activities is a priority to prevent infection. In addition, stay away from people around who have the flu or colds because these are very contagious to patients.

• Try alternative treatments

You can reduce the side effects of chemotherapy by doing alternative treatments, such as yoga, acupuncture, aromatherapy, massage, or acupressure. This treatment can reduce body fatigue, indigestion, and help manage stress.

• Routine health checks

You really need to undergo a thorough health check because of the side effects of chemo that can attack the heart. Consult this further on the cancer specialist who treats your condition.