Types of Chemotherapy - Impact and How It Works?

Table of Content

• What is Chemotherapy?
• Delivery of Chemotherapy Drugs
• How Chemotherapy Works?
• What is the Use of Chemotherapy in Cancer Treatment?
• Curative Therapy
• Adjuvant Therapy
• Neoadjuvant Therapy
• Palliative Chemotherapy
• What are the Types of Chemotherapy?
• Based on the Classes of Drugs
• Based on the Route of Administration
• How to Prepare for Chemotherapy?
• Care after Chemotherapy
• Impact of Chemotherapy Treatment
• Side Effects of Chemotherapy Treatment
• Conclusion
• Frequently Asked Questions

What is Chemotherapy?

Chemotherapy is a type of treatment recommended for patients diagnosed with different types of cancer. Chemotherapy involves delivering potent drugs that kill the rapidly growing cells in the body, including tumor or cancer cells.

Several types of chemotherapy treatments are available for the effective management of different types and stages of cancer. Patients with an early diagnosis of cancer have a more favorable prognosis with chemotherapy.

Most patients receive a combination of different chemotherapy drugs for enhanced treatment effectiveness. HCG, one of the best cancer hospitals in India, offers advanced chemotherapy options for patients dealing with a wide range of cancers.

In this article, let’s try to understand different types of chemo, the criteria on which they are categorized, how to prepare for chemotherapy, and lastly, the aftermath of chemotherapy treatments.

Delivery of Chemotherapy Drugs

The oncologists at HCG have specialized expertise in delivering chemotherapy drugs through various routes, such as oral, intravenous, and intramuscular administration.

The intravenous delivery of the drugs can be through a port, needle, catheter, or pump. Chemotherapy is generally administered in multiple cycles, and their number may vary from one case to another.

In most cases, the administration of drugs occurs within a few minutes to a few hours. However, some patients may require continuous drug infusions that may take a few days, depending on the chemotherapy treatment protocol for a particular cancer.

Continue reading to discover the various types of chemo and how they are administered.

How Chemotherapy Works?

The chemotherapy treatment has evolved significantly in recent years. We have multiple chemotherapy drug options today for different types of cancer. Medical oncologists choose the most suitable drug for each case, depending on the type and stage of the disease. In addition, the response to previous treatment also affects the choice of further treatment.

Chemotherapy drugs are categorized into different classes based on their mode of action against cancer cells. These include alkylating agents, anti-metabolites, plant alkaloids, and topoisomerase inhibitors. These drugs target the essential pathways in cancer cells and prevent their growth and multiplication.

Chemotherapy may or may not be combined with other treatment approaches, like surgery, radiotherapy, immunotherapy, and targeted therapy for enhanced effectiveness.

What is the Use of Chemotherapy in Cancer Treatment?

There are various applications of chemotherapy in cancer management. These include:

1. Curative Therapy

Chemotherapy is one of the most common treatment modalities available for different types of cancer. It may help patients achieve complete remission with minimal chances of recurrence. For example, blood cancer, lymphomas, and cancer in children.

2. Adjuvant Therapy

In most stage II and III cancers, patients may undergo various types of cancer treatment, such as surgery, radiation therapy, and chemotherapy. Adjuvant chemotherapy involves administering chemotherapy drugs after the primary treatment, which could be surgery and/or radiation therapy to destroy the remaining cancer cells.

3. Neoadjuvant Therapy

Neoadjuvant chemotherapy involves delivering the drugs before the primary treatment, which could be surgery and/or radiation therapy. Neoadjuvant chemotherapy aims to reduce the size of the tumor through chemotherapy so that it can be easily removed by surgery or treated with minimal doses/sessions of radiation therapy. This approach is usually recommended for locally advanced cancers.

4. Palliative Chemotherapy

Chemotherapy is also an important component of the palliative care strategy for patients with advanced stages of cancer. Although chemotherapy drugs may not cure cancer in such patients, they can reduce the symptoms and improve the quality of life. Some patients may live for many months to years if they respond well to treatment.

What are the Types of Chemotherapy?

1. Based on the Classes of Drugs

The types of chemotherapy treatments may be classified based on their mechanisms of action against cancer cells. The following are the different types of chemotherapy drugs:

Alkylating Agents

These agents interfere with the process of multiplication of cancer cells by damaging DNA. The cancers treated with alkylating agents include lymphoma, multiple myeloma, breast cancer, lung cancer, and ovarian cancer.

Antimetabolites

These agents interfere with cell replication and proliferation by substituting RNA and DNA with amino acids. The cancers treated with antimetabolites include ovarian cancer, breast cancer, and leukemia.

Topoisomerase Inhibitors

Topoisomerase is an enzyme that untangles DNA. Replication of DNA can only take place after untangling. Topoisomerase inhibitors block the enzyme and prevent DNA replication.

Plant Alkaloids

These drugs are also known as mitotic inhibitors. They inhibit mitosis and prevent the cancer cells from dividing. Cancers treated with plant alkaloids include myeloma, lymphoma, leukemia, and breast cancer.

Nitrosoureas

This class of chemotherapy drugs interferes with DNA replication, just like alkylating agents, and controls the growth of cancer cells.

This drug crosses the blood-brain barrier, making it an effective drug to treat different types of brain malignancies.

Anti-Tumor Antibiotics (Anthracyclines)

The antibiotics obtained from the bacterium, Streptomyces, have anti-cancer properties and are used as part of chemotherapy treatment for some cancers. This chemo drug works by causing DNA damage or preventing DNA synthesis.

2. Based on the Route of Administration

The types of chemotherapy treatment may be divided based on routes of administration. These include:

Intravenous Administration

It is one of the most common routes for delivering chemo drugs or common chemotherapy types. The route of administration is vein or blood vessel. It is usually given in drip form.

Intramuscular Administration

The route of administration of the drug involves muscles. Intramuscular chemotherapy is often administered in the upper arm, buttocks, or upper thigh.

Oral Administration

Oral administration of these drugs may be in the form of tablets or capsules.

Topical Administration

This route is generally chosen for delivering drugs to patients with skin cancer and precancerous lesions. These formulations are available in the form of creams and gels, which can be applied to the target site as prescribed by the specialist.

Intraperitoneal Chemotherapy

This route of chemotherapy administration involves direct administration of the drugs into the abdominal cavity to treat cancers of the abdominal organs, particularly the peritoneum.

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a specialized form of chemotherapy used to manage cancers that develop in the abdominal area. In the first stage, the surgical oncologist performs the surgery to remove the tumor as much as possible. Then heated chemotherapy drugs are delivered into the abdominal cavity through the catheters.

Intravesical Chemotherapy

Intravesical chemotherapy comprises the administration of chemotherapy drugs into the urinary bladder through cystoscopy. It is used for the treatment of bladder cancer.

Intrapleural Chemotherapy

Intrapleural chemotherapy involves the administration of anticancer drugs in the chest cavity/pleura to treat lung cancer.

Intrathecal Chemotherapy

Intrathecal chemotherapy drugs manage cancers of the brain and spinal cord. The drug is delivered into the intrathecal space.

How to Prepare for Chemotherapy?

Some measures may help the patients effectively prepare for medical oncology treatment. These include:

• Selecting the best cancer treatment hospital to undergo chemotherapy and other cancer treatments
• Getting detailed information about chemotherapy from the oncologists related to the duration of treatment, number of sessions, side effects, and management of those side effects
• Take effective steps beforehand to reduce the chances of the occurrence of side effects.
• Modifying the schedule to adjust according to cancer hospital visits and treatment sessions

Care after Chemotherapy

Care after chemotherapy treatment is important. It helps the patient prepare for the next chemotherapy session and improves the quality of life. Some care tips during and after medical oncology treatment include

• Avoid visiting places with increased risk of infection, e.g., closed AC halls with gatherings.
• Avoid interacting with people who have the flu or other infections.
• Eat a healthy diet
• Avoid eating food that is spoiled or undercooked; preferably, eat homemade, freshly cooked food.
• Drink safe drinking water.
• Take adequate rest and have good quality sleep.
• Do not skip the follow-up schedule.
• Immediately consult the doctor if there is any concern/unusual symptom.

Impact of Chemotherapy Treatment

Several factors affect the efficacy of chemotherapy treatment. These include types and stages of cancer, response to treatment, severity of side effects, age of the patient, and overall health/performance status.

Further, oncologists critically monitor the effect of chemotherapy, and based on the evaluation, they may continue the treatment, add more drugs to the treatment regimen, or switch the patient to another treatment option. Upon completing their chemotherapy treatment, patients need to keep up their follow-up appointments, which can help them achieve long-term remission and reduce the risk of recurrences.

Side Effects of Chemotherapy Treatment

Chemotherapy treatment may cause both short- and long-term side effects. Most of these side effects subside on their own within a span of a few weeks. However, if these side effects are severe, patients must reach out to their expert team. Different short-term side effects include:

• Fever
• Fatigue
• Loss of appetite
• Diarrhea
• Nausea
• Vomiting
• Constipation
• Pain
• Oral sores
• Change in taste
• Hair loss

The long-term side effects of chemotherapy include:

• Change in cardiac functioning/LVEF
• Lung problems
• Neurological problems like peripheral neuropathy
• Kidney problems
• Sometimes, infertility

Conclusion

Chemotherapy plays a vital role in the management of cancer. It targets and kills cancer cells. It improves the survival rate for several types of cancer, especially when cancer is diagnosed early. The factors affecting the choice of chemotherapy include the type and stage of cancer, treatment goals, and the patient's overall health. In some cases, patients can receive their chemotherapy infusion on an outpatient basis, which causes fewer disruptions to their day-to-day life.

Frequently Asked Questions

How many types of chemotherapy treatment are there?

Chemotherapy is categorized into various types, depending on the intent of the treatment, the class of the drugs (chemotherapy medications), and the mode of administration.

Based on the intent of the treatment: curative, neoadjuvant (given before the primary treatment), adjuvant (given after the primary treatment), and palliative.

Based on the class of the drugs: alkylating agents, antimetabolites, topoisomerase inhibitors, plant alkaloids, nitrosoureas, and anti-tumor antibiotics.

Based on the mode of administration: intravenous, intramuscular, oral, topical, intraperitoneal (for abdominal cavity), intravesical (for urinary bladder), intrapleural (for chest cavity), and intrathecal (for brain and spinal cord).

What are the 4 levels of chemotherapy?

Chemotherapy is generally administered in three phases: induction, consolidation, and maintenance.

• Induction: An intense phase that destroys as many cancer cells as possible to put the patient in remission.
• Consolidation: This phase of chemotherapy aims to kill the residual cancer cells with low-dose chemotherapy.
• Maintenance: The maintenance phase aims to reduce the risk of recurrences and help patients achieve long-term remission.

There is no fourth phase or level.

What is the most common type of chemotherapy?

Alkylating agents are the most common type of chemotherapy. This class of chemotherapy drugs controls the growth of cancer cells by damaging their DNA structure.

Alkylating agents are used to treat both solid and hematological malignancies.

Which chemo is stronger?

Identifying one chemo drug as the strongest one is not possible. Each drug has its own strengths and drawbacks. Additionally, not all cancer patients can be treated with one chemotherapy drug just because it is more powerful.

For chemotherapy, the drugs are selected based on individual case parameters, such as the type of cancer, its stage and grade, the patient’s overall health status, and the treatment goal.

What is the biggest side effect of chemo?

The side effects caused by chemotherapy can vary from one patient to another, both in severity and duration. Some patients may experience severe fatigue, while others experience moderate fatigue. Therefore, it is difficult to identify one side effect as the biggest one.

That said, the different side effects of chemotherapy include fever, fatigue, loss of appetite, diarrhea, nausea, vomiting, pain, mouth sores, change in taste, and hair loss.

References

Cancer Chemotherapy | NCBI

SEER Training: Introduction to Chemotherapy

SEER Training: Types of Chemotherapy Drugs

Chemotherapy to Treat Cancer - NCI

Types of Cancer Treatment - NCI

Dr. Kshitij Domadia is an ESMO (European Society of Medical Oncology)-certified medical oncologist (ECMO) with a special interest in the management of lung cancers, head and neck cancers, genitourinary cancers, and breast cancers. He is available for consultations at HCG Aastha Cancer Centre, a leading oncology hospital in Ahmedabad. He is an expert in dealing with all sorts of chemotherapy, targeted therapy, and immunotherapy in its most rational manner. His expertise in dealing with molecular aspects of oncology and precision oncology is very well acclaimed by the community. Dr. Kshitij approaches his patient care with empathy, care, and compassion, in addition to his thorough academic knowledge.

To book an appointment with Dr. Kshitij Domadia, please click here.