How Chemotherapy destroy cancer cells

Chemotherapy requires the use of drugs to destroy cancer cells. Although the ideal drug would destroy cancer cells without harming normal cells, most drugs are not selective. Instead, drugs are designed to inflict greater damage on cancer cells than normal cells, usually by using drugs that affect the ability of cells to grow.

Uncontrolled growth and fast is the hallmark of cancer cells. But because normal cells also need to grow, and some grow quite quickly (as in bone marrow and a line along the mouth and intestines), all chemotherapy drugs affect normal cells and cause side effects.

A new approach to limiting side effects and increase the effectiveness of the use of drugs that "in the direction of the molecular". These drugs kill cancer cells by attacking channels and processes vital to the survival and growth of cancer cells. For example, cancer cells need blood vessels to deliver nutrients and oxygen. Some drugs can block the formation of blood vessels to cancer cells or the master signaling pathways that control cell growth.

Imatinib, the first such drug, is highly effective for chronic myelocytic leukemia and certain cancers of the digestive tract. Erlotinib and gefitinib to receptors located on the cell surface on cell lung cancer non-small cancer. Molecularly targeted drugs have proven useful in treating many other cancers, including breast and kidney cancer.

Not all cancers respond to chemotherapy. This type of cancer determines which drugs are used, in what combination, and at what dose. Chemotherapy may be used as the sole treatment or combined with radiation therapy or surgery, or both.

High-Dose Chemotherapy: In an attempt to enhance the antitumor effects of cancer drugs, the dose may be increased and the time between cycles of therapy may be decreased (dose-dense chemotherapy). Dose-dense chemotherapy, with a shortened period, is routinely used in the treatment of breast cancer. High-dose chemotherapy is often used for treatment of people with cancer has recurred after standard-dose therapy, particularly for people with myeloma, lymphoma, and leukemia. However, high-dose chemotherapy can cause life-threatening injury in the bone marrow. Therefore, high-dose chemotherapy is commonly combined with bone marrow rescue strategies. In the bone marrow that was saved, removed bone marrow cells before chemotherapy and returned after chemotherapy. In some cases, stem cells can be isolated from the bloodstream from the bone marrow and can be infused into the patient after chemotherapy to restore bone marrow function.


Side Effects

Chemotherapy commonly causes nausea, vomiting, loss of appetite, weight loss, fatigue, and low blood cell count which causes anemia and increased risk of infection. With chemotherapy, people often lose their hair, but other side effects vary according to the type of drug.

Nausea and vomiting: These symptoms can usually be prevented or reduced by drugs (antiemetics). Nausea may also be reduced by eating small meals and avoiding foods high in fiber.

Low Blood Cell Counts: Cytopenia, a deficiency of one or more types of blood cells, can occur due to the toxic effects of chemotherapy drugs in bone marrow (where blood cells are made). For example, patients may have low red blood cells are abnormal (anemia), white blood cells (neutropenia or leukopenia) or platelets (thrombocytopenia). If anemia is severe, specific growth factors, such as erythropoietin or darbepoietin, can be given to the formation of red blood cells or red blood cells can be transfused. If thrombocytopenia is severe, platelets can be transfused to lower the risk of bleeding.

People with neutropenia increases the risk of infection. Fever higher than 100.4 F in patients with neutropenia is considered as an emergency. People like that should be evaluated for infection and may require antibiotics or hospitalization. White blood cells are rarely transfused because, when transfused, they continue to live only a few hours and produce many side effects. In fact, certain materials (such as granulocyte colony stimulating factor) may be given to stimulate the production of white blood cells.

Side effects occur more frequently: Many people develop inflammation or injury to the mucous membranes, such as the lining of the mouth. Mouth sores and felt pain in the mouth can make eating difficult. Various oral solution (usually containing antacids, antihistamines, and local anesthetic) can reduce the discomfort. On rare occasions, people need nutritional support with a feeding tube placed directly into the stomach or small intestine or a vein. Types of drugs can reduce diarrhea caused by radiation therapy to the abdomen.

People who are treated with chemotherapy, particularly alkylating compounds, may have an increased risk of developing leukemia several years after treatment. Some drugs, especially alkylating agents, cause infertility in some women and most men who receive these treatments.