Treatment of Cancer Cancer treatment involves various medical approaches aimed at eliminating cancerous cells, controlling their growth, and preventing recurrence. The choice of treatment depends on the type, location, and stage of cancer, as well as the patient’s overall health. Common treatment modalities include surgery (removal of tumors), chemotherapy (use of drugs to kill or stop the growth of cancer cells), radiation therapy (targeted use of high-energy radiation), immunotherapy (boosting the body’s immune response to fight cancer), and targeted therapy (drugs that specifically target cancer cell mechanisms). In some cases, hormone therapy, stem cell transplant, or precision medicine may also be used. Often, a combination of treatments is employed for optimal effectiveness. Advancements in technology and research continue to improve outcomes and offer new hope in the fight against cancer.

1. Treatment of Cancer
Dr. Deepak P
Unit - 4

2. https://oncolifehospitals.com/2024/06/04/make-informed-decisions-know-your-cancer-
treatment-options/

3. Treatment of Cancer
Cancer treatment aims to eradicate cancer cells while minimizing harm to
normal tissues.
The choice of treatment depends on the type, stage, and location of
cancer, as well as the patient’s overall health.
The three primary treatment approaches are chemotherapy, radiotherapy,
and immunotherapy, which are often used alone or in combination.

4. 1. Chemotherapy
Chemotherapy is a systemic treatment that uses
chemical agents to kill cancer cells or prevent
their division.
It is commonly used for blood cancers (leukemia,
lymphoma), metastatic cancers, and solid
tumors that cannot be surgically removed.
https://www.cancer.gov/publications/dictionaries/
cancer-terms/def/intravenous-chemotherapy

5. Mechanism of Action
Chemotherapy drugs work by targeting rapidly dividing cells, which
includes both cancer cells and some normal cells (e.g., bone marrow, hair
follicles, and the digestive tract lining).
These drugs disrupt the cell cycle at different stages, leading to DNA
damage, mitotic arrest, and apoptosis (programmed cell death).
Some chemotherapeutic agents generate reactive oxygen species (ROS),
causing oxidative stress and cellular damage.

6. DOI: 10.21577/0103-5053.20230128

7. Types of Chemotherapy Drugs
1. Alkylating Agents

Form covalent bonds with DNA, leading to cross-linking and strand breakage.

Examples: Cyclophosphamide, Cisplatin, Ifosfamide, Busulfan.

Used for: Lymphomas, lung cancer, breast cancer, ovarian cancer.
2. Antimetabolites

Mimic natural cell metabolites, interfering with DNA and RNA synthesis.

Examples: Methotrexate (folate analog), 5-Fluorouracil (pyrimidine analog), Cytarabine.

Used for: Leukemia, colorectal cancer, pancreatic cancer

8. Types of Chemotherapy Drugs
3. Mitotic Inhibitors (Plant Alkaloids)
Block microtubule formation, preventing cell division.
Examples: Vincristine, Vinblastine, Paclitaxel (Taxol).
Used for: Breast cancer, lung cancer, leukemia.
Catharanthus

9. 4. Topoisomerase Inhibitors
Interfere with DNA unwinding during replication, leading to strand breaks.
Examples: Doxorubicin (Adriamycin), Etoposide, Irinotecan.
Used for: Lung cancer, colorectal cancer, leukemia.
5. Targeted Therapy (Modern Chemotherapy)
Targets specific molecular pathways unique to cancer cells, minimizing side effects.
Examples: Imatinib (CML), Trastuzumab (HER2+ breast cancer), Bevacizumab (VEGF
inhibitor).
Types of Chemotherapy Drugs

10. Side Effects of Chemotherapy
Myelosuppression (low RBCs, WBCs, platelets) Infections, anemia, bleeding.
→
Gastrointestinal toxicity Nausea, vomiting, diarrhea, mucositis.
→
Hair loss (Alopecia) due to damage to hair follicle cells.
Neuropathy (nerve damage), especially with platinum-based drugs.
Cardiotoxicity (Doxorubicin can cause heart damage).

11. Advancements in Chemotherapy
Liposomal Drug Delivery – Encapsulating drugs in liposomes to reduce
toxicity.
Nanoparticle-based Chemotherapy – Selective targeting of cancer cells
using nanocarriers.
Personalized Medicine – Genetic testing to determine the most
effective chemotherapy regimen.

12. 2. Radiotherapy
Radiotherapy uses high-energy radiation to
damage the DNA of cancer cells, leading
to cell death.
It is primarily used for solid tumors and
can be used alone or in combination with
surgery and chemotherapy.
https://blog.virginiacancer.com/
improved-options-for-radiotherapy-
patients-with-brain-metastases

13. Mechanism of Action
Radiation causes double-strand breaks (DSBs)
in DNA, which cancer cells struggle to repair.
It also generates free radicals, causing
oxidative stress that leads to apoptosis.
Cancer cells, due to their high mitotic rate, are
more susceptible to radiation damage compared
to normal cells.
Int J Med Sci 2012; 9(3):193-
199. doi:10.7150/ijms.3635

14. Types of Radiotherapy
1. External Beam Radiotherapy (EBRT)
A linear accelerator directs X-rays or gamma rays at the tumor from outside the body.
Used for: Brain tumors, lung cancer, prostate cancer, head and neck cancers.
2. Brachytherapy (Internal Radiation Therapy)
Radioactive materials (seeds, wires, or rods) are implanted inside or near the tumor.
Used for: Prostate cancer, cervical cancer, breast cancer.

15. Types of Radiotherapy
3. Systemic Radiotherapy
Radioactive substances are
administered intravenously or
orally to target cancer cells.
Example: Iodine-131 for thyroid
cancer, Radium-223 for bone
metastases.
https://www.utsouthwestern.edu/newsroom/articles/
year-2022/stereotactic-radiation-extends-systemic-
therapy.html

16. Side Effects of Radiotherapy
• Acute Side Effects:
• Skin reactions (burns, peeling, redness).
• Fatigue due to energy depletion.
• Nausea and loss of appetite.
• Chronic Side Effects:
• Fibrosis (stiffening of tissues).
• Secondary cancers (mutation-induced malignancies).

17. Advancements in Radiotherapy
Proton Beam Therapy – Uses protons instead of X-rays for precise
targeting.
Stereotactic Radiosurgery (SRS) – Focused, high-dose radiation
for brain tumors.
Image-Guided Radiotherapy (IGRT) – Uses real-time imaging for
accurate radiation delivery.

18. 3. Immunotherapy
Immunotherapy boosts the
immune system to fight
cancer more effectively.
Unlike chemotherapy and
radiotherapy, which directly
target cancer cells,
immunotherapy enhances the
body's natural defenses.
https://
www.arizonabloodandcancerspecialists.com/what-is-

19. Mechanism of Action
Cancer cells often evade immune detection by expressing immune
checkpoint molecules (e.g., PD-L1).
Immunotherapy disrupts these signals, allowing T-cells to attack cancer
cells.
Some therapies involve genetically modifying immune cells to enhance
their ability to target tumors.

20. Types of Immunotherapy
1. Checkpoint Inhibitors
Block immune checkpoints like PD-1, PD-L1, and CTLA-4, restoring T-cell activity.
Examples: Pembrolizumab (Keytruda), Nivolumab, Ipilimumab.
Used for: Melanoma, lung cancer, bladder cancer.
2. Monoclonal Antibodies (mAbs)
Artificial antibodies bind to specific cancer cell antigens and trigger an immune
response.
Examples: Trastuzumab (HER2+ breast cancer), Rituximab (B-cell lymphoma).

21. 3. Cancer Vaccines
Stimulate the immune system to recognize and fight cancer cells.
Examples: HPV vaccine (cervical cancer), Sipuleucel-T (prostate
cancer).
4. CAR-T Cell Therapy
T cells are extracted from the patient, genetically engineered to
express chimeric antigen receptors (CARs), and re-infused to attack
tumors.
Examples: Tisagenlecleucel (leukemia), Axicabtagene ciloleucel
(lymphoma).

22. 5. Cytokine Therapy
Involves the use of interleukins and interferons to enhance
immune activity.
Example: IL-2 (melanoma, kidney cancer), IFN-alpha
(leukemia, lymphoma).

23. Side Effects of Immunotherapy
Autoimmune reactions (e.g., inflammation of organs).
Skin rashes, fatigue, and flu-like symptoms.
Risk of cytokine release syndrome (CRS), causing severe immune
overactivation.

24. Advancements in Immunotherapy
mRNA Cancer Vaccines – Personalized vaccines targeting patient-specific
mutations.
Combination Therapy – Combining checkpoint inhibitors with chemotherapy
or radiation for synergistic effects.
Tumor-Infiltrating Lymphocyte (TIL) Therapy – Harvesting and expanding a
patient’s immune cells to attack cancer.