Cancer treatment modalities

1. CANCER TREATMENT
MODALITIES
WILBERT A. CABANBAN, RN,MAN

2. CHEMOTHERAPY
• Chemotherapy is a drug treatment that uses powerful chemicals to kill fast-
growing cells in your body.
• Chemotherapy is most often used to treat cancer, since cancer cells grow and
multiply much more quickly than most cells in the body.
• Many different chemotherapy drugs are available. Chemotherapy drugs can be
used alone or in combination to treat a wide variety of cancers.
• Though chemotherapy is an effective way to treat many types of cancer,
chemotherapy treatment also carries a risk of side effects. Some chemotherapy
side effects are mild and treatable, while others can cause serious complications.

3. Types of Chemotherapy
Alkylating Agents
Alkylating agents are most active in the resting phase of the cell. These types of drugs are cell-
cycle non-specific. There are several types of alkylating agents used in chemotherapy treatments:
• Mustard gas derivatives: Mechlorethamine, Cyclophosphamide, Chlorambucil, Melphalan, and
Ifosfamide.
• Ethylenimines: Thiotepa and Hexamethylmelamine.
• Alkylsulfonates: Busulfan.
• Hydrazines and Triazines: Altretamine, Procarbazine, Dacarbazine and Temozolomide.
• Nitrosureas: Carmustine, Lomustine and Streptozocin. Nitrosureas are unique because, unlike
most types of chemo treatments, they can cross the blood-brain barrier. They can be useful in
treating brain tumors.
• Metal salts: Carboplatin, Cisplatin, and Oxaliplatin.

4. Plant Alkaloids
Plant alkaloids are chemotherapy treatments derived made from certain types
of plants. The vinca alkaloids are made from the periwinkle plant (catharanthus
rosea). The taxanes are made from the bark of the Pacific Yew tree (taxus). The
vinca alkaloids and taxanes are also known as antimicrotubule agents. The
podophyllotoxins are derived from the May apple plant. Camptothecan analogs are
derived from the Asian "Happy Tree" (Camptotheca acuminata). Podophyllotoxins
and camptothecan analogs are also known as topoisomerase inhibitors, which are
used in certain types of chemotherapy. The plant alkaloids are cell-cycle
specific. This means they attack the cells during various phases of division.

5. • Vinca alkaloids: Vincristine, Vinblastine and Vinorelbine.
• Taxanes: Paclitaxel and Docetaxel.
• Podophyllotoxins: Etoposide and Tenisopide.
• Camptothecan analogs: Irinotecan and Topotecan.

6. Antitumor Antibiotics
Antitumor antibiotics are chemo treatments made from natural products
produced by species of the soil fungus Streptomyces. These drugs act during
multiple phases of the cell cycle and are considered cell-cycle specific. There are
several types of antitumor antibiotics:
• Anthracyclines: Doxorubicin, Daunorubicin, Epirubicin, Mitoxantrone, and
Idarubicin.
• Chromomycins: Dactinomycin and Plicamycin.
• Miscellaneous: Mitomycin and Bleomycin.

7. Antimetabolites
Antimetabolites are types of chemotherapy treatments that are very similar to
normal substances within the cell. When the cells incorporate these substances into
the cellular metabolism, they are unable to divide. Antimetabolites are cell-cycle
specific. They attack cells at very specific phases in the cycle. Antimetabolites are
classified according to the substances with which they interfere.

8. • Folic acid antagonist: Methotrexate.
• Pyrimidine antagonist: 5-Fluorouracil, Foxuridine, Cytarabine, Capecitabine, and
Gemcitabine.
• Purine antagonist: 6-Mercaptopurine and 6-Thioguanine.
• Adenosine deaminase inhibitor: Cladribine, Fludarabine, Nelarabine and
Pentostatin.

9. Topoisomerase Inhibitors
Toposiomerase inhibitors are types of chemotherapy drugs that interfere with the
action of topoisomerase enzymes (topoisomerase I and II). During the process of
chemo treatments, topoisomerase enzymes control the manipulation of the structure
of DNA necessary for replication.
• Topoisomerase I inhibitors: Ironotecan, topotecan
• Topoisomerase II inhibitors: Amsacrine, etoposide, etoposide phosphate,
teniposide

10. Miscellaneous Antineoplastics
• Several useful types of chemotherapy drugs are unique:
• Ribonucleotide reductase inhibitor: Hydroxyurea.
• Adrenocortical steroid inhibitor: Mitotane
• Enzymes: Asparaginase and Pegaspargase.
• Antimicrotubule agent: Estramustine
• Retinoids: Bexarotene, Isotretinoin, Tretinoin (ATRA)

11. Chemotherapy Side Effects
What causes side effects?
Cancer cells tend to grow fast, and chemo drugs kill fast-growing cells. These
drugs travel throughout the body, they can affect normal, healthy cells that are fast-
growing, too. Damage to healthy cells causes side effects.
The normal cells most likely to be damaged by chemo are :
• Blood-forming cells in the bone marrow
• Hair follicles
• Cells in the mouth, digestive tract, and reproductive system
• Some chemo drugs can damage cells in the heart, kidneys, bladder, lungs, and nervous
system.

12. RADIATION THERAPY
Radiation therapy (also called radiotherapy) is a cancer treatment that uses
high doses of radiation to kill cancer cells and shrink tumors. At low doses, radiation
is used in x-rays to see inside your body, as with x-rays of your teeth or broken
bones.

13. At high doses, radiation kills cancer cells or slows their growth. Radiation therapy is
used to:
• Treat cancer
Radiation can be used to cure cancer, to prevent it from returning, or to stop or
slow its growth.
• Ease cancer symptoms
Radiation may be used to shrink a tumor to treat pain and other problems caused
by the tumor. Or, it can lessen problems that may be caused by a growing tumor,
such as trouble breathing or loss of bowel and bladder control.

14. Radiation therapy does not kill cancer cells right away. It takes days or weeks of
treatment before cancer cells start to die. Then, cancer cells keep dying for weeks or
months after radiation therapy ends.

15. Types of Radiation Therapy
External beam radiation therapy
External beam radiation therapy (EBRT) directs a beam of radiation from outside
the body at cancerous tissues inside the body. It is a cancer treatment option that
uses doses of radiation to destroy cancerous cells and shrink tumors.
EBRT delivers high-energy rays to tumors, using a special X-ray machine called
a linear accelerator. This machine allows radiation to be delivered from any angle and
shapes radiation beams to the contour of the tumor. The machine moves around the
body without touching the patient and aims radiation at the cancer.

17. Internal Radiation Therapy (Brachytherapy)
Internal radiation is also called brachytherapy. A radioactive implant is put inside the
body in or near the tumor.
Internal radiation therapy (brachytherapy) allows a higher dose of radiation in a
smaller area than might be possible with external radiation treatment. It uses a radiation
source that’s usually sealed in a small holder called an implant. Different types of implants
may be called pellets, seeds, ribbons, wires, needles, capsules, balloons, or tubes. No
matter which type of implant is used, it is placed in the body, very close to or inside the
tumor. This way the radiation harms as few normal cells as possible.

18. • During intracavitary radiation, the radioactive source is placed in a body cavity
(space) , such as the rectum or uterus.
• With interstitial radiation, the implants are placed in or near the tumor, but not in
a body cavity.

19. High-dose rate brachytherapy
High-dose-rate (HDR) brachytherapy allows a person to be treated for only a few
minutes at a time with a powerful radioactive source that’s put in the applicator. The
source is removed after several minutes. This may be repeated over the course of a
few days to weeks. The radioactive material is not left in your body. The applicator
might be left in place between treatments, or it might be put in before each treatment.

20. Low-dose-rate brachytherapy
In this approach, the implant gives off lower doses of radiation over a longer period.
Some implants are left in from 1 to a few days and then removed. You’ll probably
have to stay in the hospital, sometimes in a special room, during treatment. For larger
implants, you might have to stay in bed and lie still to keep it from moving.
Some smaller implants (such as the seeds or pellets) are left in place – they’re never
taken out. Over the course of several weeks they stop giving off radiation. The seeds are
about the size of rice grains and rarely cause problems. If your implants are to be left in,
you may be able to go home the same day they’re put in.