Types of Treatment For Cancer

Types of Treatment For Cancer

1.Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to destroy cancer cells.Chemotherapy can be used to destroy cancer cells,stop cancer cells from spreading or slow the growth of cancer cells.

Chemotherapy Side Effects:

-Anemia

-Appetite Changes

-Bleeding Problems

-Constipation

-Diarrhea

-Fatigue (Feeling Weak and Very Tired)

-Hair Loss (Alopecia)

-Infection

-Memory Changes

-Mouth and Throat Changes

-Nausea and Vomiting

-Nerve Changes

-Pain

-Sexual and Fertility Changes in Men

-Sexual and Fertility Changes in Women

-Skin and Nail Changes

-Swelling (Fluid Retention)

-Urination Changes

2.Radiation Therapy

Radiation therapy uses high-energy radiation to shrink tumors and kill cancer cells . X-rays, gamma rays, and charged particles are types of radiation used for cancer treatment.The radiation may be delivered by a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy, also called brachytherapy).Systemic radiation therapy uses radioactive substances, such as radioactive iodine, that travel in the blood to kill cancer cells.

Radiation therapy kills cancer cells by damaging their DNA (the molecules inside cells that carry genetic information and pass it from one generation to the next) . Radiation therapy can either damage DNA directly or create charged particles (free radicals) within the cells that can in turn damage the DNA.Cancer cells whose DNA is damaged beyond repair stop dividing or die. When the damaged cells die, they are broken down and eliminated by the body’s natural processes.

3.Cryosurgery

Cryosurgery  is the use of extreme cold produced by liquid nitrogen (or argon gas) to destroy abnormal tissue. Cryosurgery is used to treat external tumors, such as those on the skin. For external tumors, liquid nitrogen is applied directly to the cancer cells with a cotton swab or spraying device.Cryosurgery is also used to treat tumors inside the body (internal tumors and tumors in the bone). For internal tumors, liquid nitrogen or argon gas is circulated through a hollow instrument called a cryoprobe, which is placed in contact with the tumor. The doctor uses ultrasound or MRI to guide the cryoprobe and monitor the freezing of the cells, thus limiting damage to nearby healthy tissue. (In ultrasound, sound waves are bounced off organs and other tissues to create a picture called a sonogram.) A ball of ice crystals forms around the probe, freezing nearby cells. Sometimes more than one probe is used to deliver the liquid nitrogen to various parts of the tumor. The probes may be put into the tumor during surgery or through the skin (percutaneously). After cryosurgery, the frozen tissue thaws and is either naturally absorbed by the body (for internal tumors), or it dissolves and forms a scab (for external tumors). 

Cryosurgery is used to treat several types of cancer, and some precancerous or noncancerous conditions. In addition to prostate and liver tumors, cryosurgery can be an effective treatment for the following:

-Retinoblastoma (a childhood cancer that affects the retina of the eye). Doctors have found that cryosurgery is most effective when the tumor is small and only in certain parts of the retina.

-Early-stage skin cancers (both basal cell and squamous cell carcinomas).

-Precancerous skin growths known as actinic keratosis.

-Precancerous conditions of the cervix known as cervical intraepithelial neoplasia (abnormal cell changes in the cervix that can develop into cervical cancer).

Cryosurgery is also used to treat some types of low-grade cancerous and noncancerous tumors of the bone. It may reduce the risk of joint damage when compared with more extensive surgery, and help lessen the need for amputation. The treatment is also used to treat AIDS-related Kaposi sarcoma when the skin lesions are small and localized.

Researchers are evaluating cryosurgery as a treatment for a number of cancers, including breast, colon, and kidney cancer. They are also exploring cryotherapy in combination with other cancer treatments, such as hormone therapy, chemotherapy, radiation therapy, or surgery. 

4.Transplantation

Bone marrow is the soft, sponge-like material found inside bones. It contains immature cells known as hematopoietic or blood-forming stem cells. (Hematopoietic stem cells are different from embryonic stem cells. Embryonic stem cells can develop into every type of cell in the body.) Hematopoietic stem cells divide to form more blood-forming stem cells, or they mature into one of three types of blood cells: white blood cells, which fight infection; red blood cells, which carry oxygen; and platelets, which help the blood to clot. Most hematopoietic stem cells are found in the bone marrow, but some cells, called peripheral blood stem cells (PBSCs), are found in the bloodstream. Blood in the umbilical cord also contains hematopoietic stem cells. Cells from any of these sources can be used in transplants.

Bone marrow transplantation (BMT) and peripheral blood stem cell transplantation (PBSCT) are procedures that restore stem cells that have been destroyed by high doses of chemotherapy and/or radiation therapy. There are three types of transplants:

-In autologous transplants, patients receive their own stem cells.

-In syngeneic transplants, patients receive stem cells from their identical twin.

-In allogeneic transplants, patients receive stem cells from their brother, sister, or parent. A person who is not related to the patient (an unrelated donor) also may be used.

5.Angiogenesis Inhibition 

Angiogenesis is the formation of new blood vessels. This process involves the migration, growth, and differentiation of endothelial cells, which line the inside wall of blood vessels.The process of angiogenesis is controlled by chemical signals in the body. These signals can stimulate both the repair of damaged blood vessels and the formation of new blood vessels. Other chemical signals, called angiogenesis inhibitors, interfere with blood vessel formation. Normally, the stimulating and inhibiting effects of these chemical signals are balanced so that blood vessels form only when and where they are needed.

Angiogenesis plays a critical role in the growth and spread of cancer. A blood supply is necessary for tumors to grow beyond a few millimeters in size. Tumors can cause this blood supply to form by giving off chemical signals that stimulate angiogenesis. Tumors can also stimulate nearby normal cells to produce angiogenesis signaling molecules. The resulting new blood vessels “feed” growing tumors with oxygen and nutrients, allowing the cancer cells to invade nearby tissue, to move throughout the body, and to form new colonies of cancer cells, called metastases.Because tumors cannot grow beyond a certain size or spread without a blood supply, scientists are trying to find ways to block tumor angiogenesis. They are studying natural and synthetic angiogenesis inhibitors, also called antiangiogenic agents, with the idea that these molecules will prevent or slow the growth of cancer.

Angiogenesis requires the binding of signaling molecules, such as vascular endothelial growth factor (VEGF), to receptors on the surface of normal endothelial cells. When VEGF and other endothelial growth factors bind to their receptors on endothelial cells, signals within these cells are initiated that promote the growth and survival of new blood vessels.

Angiogenesis inhibitors interfere with various steps in this process. For example, bevacizumab  is a monoclonal antibody that specifically recognizes and binds to VEGF . When VEGF is attached to bevacizumab, it is unable to activate the VEGF receptor. Other angiogenesis inhibitors, including sorafenib and sunitinib, bind to receptors on the surface of endothelial cells or to other proteins in the downstream signaling pathways, blocking their activities.

6.Biological Therapy

Biological therapy  is a type of treatment that works with your immune system. It can help fight cancer or help control side effects from other cancer treatments like chemotherapy.Biological therapy and chemotherapy are both treatments that fight cancer. While they may seem alike, they work in different ways. Biological therapy helps your immune system fight cancer. Chemotherapy attacks the cancer cells directly.

7.Gene Therapy 

Gene therapy is an experimental treatment that involves introducing genetic material (DNA or RNA) into a person's cells to fight disease. Gene therapy is being studied in clinical trials (research studies with people) for many different types of cancer and for other diseases. It is not currently available outside a clinical trial.Researchers are studying several ways to treat cancer using gene therapy. Some approaches target healthy cells to enhance their ability to fight cancer. Other approaches target cancer cells, to destroy them or prevent their growth.

8.Hyperthermia Therapy 

Hyperthermia is a type of cancer treatment in which body tissue is exposed to high temperatures (up to 113°F). Research has shown that high temperatures can damage and kill cancer cells, usually with minimal injury to normal tissues . By killing cancer cells and damaging proteins and structures within cells , hyperthermia may shrink tumors.

Hyperthermia is almost always used with other forms of cancer therapy, such as radiation therapy and chemotherapy . Hyperthermia may make some cancer cells more sensitive to radiation or harm other cancer cells that radiation cannot damage. When hyperthermia and radiation therapy are combined, they are often given within an hour of each other. Hyperthermia can also enhance the effects of certain anticancer drugs.Numerous clinical trials have studied hyperthermia in combination with radiation therapy and/or chemotherapy. These studies have focused on the treatment of many types of cancer, including sarcoma, melanoma, and cancers of the head and neck, brain, lung, esophagus, breast, bladder, rectum, liver, appendix, cervix, and peritoneal lining (mesothelioma) . Many of these studies, but not all, have shown a significant reduction in tumor size when hyperthermia is combined with other treatments . However, not all of these studies have shown increased survival in patients receiving the combined treatments .

9.Lasers Therapy 

Laser therapy uses high-intensity light to treat cancer and other illnesses. Lasers can be used to shrink or destroy tumors or precancerous growths. Lasers are most commonly used to treat superficial cancers (cancers on the surface of the body or the lining of internal organs) such as basal cell skin cancer and the very early stages of some cancers, such as cervical, penile, vaginal, vulvar, and non-small cell lung cancer.Lasers also may be used to relieve certain symptoms of cancer, such as bleeding or obstruction. Lasers also can be used to remove colon polyps or tumors that are blocking the colon or stomach.Laser therapy can be used alone, but most often it is combined with other treatments, such as surgery, chemotherapy, or radiation therapy. In addition, lasers can seal nerve endings to reduce pain after surgery and seal lymph vessels to reduce swelling and limit the spread of tumor cells.

10.Photodynamic Therapy 

Photodynamic therapy (PDT) is a treatment that uses a drug, called a photosensitizer or photosensitizing agent, and a particular type of light. When photosensitizers are exposed to a specific wavelength of light, they produce a form of oxygen that kills nearby cells.Each photosensitizer is activated by light of a specific wavelength. This wavelength determines how far the light can travel into the body. Thus, doctors use specific photosensitizers and wavelengths of light to treat different areas of the body with PDT.

In the first step of PDT for cancer treatment, a photosensitizing agent is injected into the bloodstream. The agent is absorbed by cells all over the body but stays in cancer cells longer than it does in normal cells. Approximately 24 to 72 hours after injection , when most of the agent has left normal cells but remains in cancer cells, the tumor is exposed to light. The photosensitizer in the tumor absorbs the light and produces an active form of oxygen that destroys nearby cancer cells.

In addition to directly killing cancer cells, PDT appears to shrink or destroy tumors in two other ways . The photosensitizer can damage blood vessels in the tumor, thereby preventing the cancer from receiving necessary nutrients. PDT also may activate the immune system to attack the tumor cells.The light used for PDT can come from a laser or other sources . Laser light can be directed through fiber optic cables (thin fibers that transmit light) to deliver light to areas inside the body . For example, a fiber optic cable can be inserted through an endoscope (a thin, lighted tube used to look at tissues inside the body) into the lungs or esophagus to treat cancer in these organs. Other light sources include light-emitting diodes (LEDs), which may be used for surface tumors, such as skin cancer .

PDT is usually performed as an outpatient procedure. PDT may also be repeated and may be used with other therapies, such as surgery, radiation, or chemotherapy.Extracorporeal photopheresis (ECP) is a type of PDT in which a machine is used to collect the patient’s blood cells, treat them outside the body with a photosensitizing agent, expose them to light, and then return them to the patient.

11.Targeted Cancer Therapy

Targeted cancer therapies are drugs or other substances that block the growth and spread of cancer by interfering with specific molecules involved in tumor growth and progression. Because scientists often call these molecules “molecular targets,” targeted cancer therapies are sometimes called “molecularly targeted drugs,” “molecularly  targeted therapies,” or other similar names. By focusing on molecular and cellular changes that are specific to cancer, targeted cancer therapies may be more effective than other types of treatment, including chemotherapy and radiotherapy, and less harmful to normal cells.

Targeted cancer therapies interfere with cancer cell division (proliferation) and spread in different ways. Many of these therapies focus on proteins that are involved in cell signaling pathways, which form a complex communication system that governs basic cellular functions and activities, such as cell division, cell movement, cell responses to specific external stimuli, and even cell death. By blocking signals that tell cancer cells to grow and divide uncontrollably, targeted cancer therapies can help stop cancer progression and may induce cancer cell death through a process known as apoptosis. Other targeted therapies can cause cancer cell death directly, by specifically inducing apoptosis, or indirectly, by stimulating the immune system to recognize and destroy cancer cells and/or by delivering toxic substances directly to the cancer cells.The development of targeted therapies, therefore, requires the identification of good targets—that is, targets that are known to play a key role in cancer cell growth and survival. 

For example, most cases of chronic myeloid leukemia (CML) are caused by the formation of a gene called BCR-ABL. This gene is formed when pieces of chromosome 9 and chromosome 22 break off and trade places. One of the changed chromosomes resulting from this switch contains part of the ABL gene from chromosome 9 fused to part of the BCR gene from chromosome 22. The protein normally produced by the ABL gene (Abl) is a signaling molecule that plays an important role in controlling cell proliferation and usually must interact with other signaling molecules to be active. However, Abl signaling is always active in the protein (Bcr-Abl) produced by the BCR-ABL fusion gene. This activity promotes the continuous proliferation of CML cells. Therefore, Bcr-Abl represents a good molecule to target.

The Biology of Cancer:Click the link below to watch.
Cancer Biology