According to the World Health Organization, cancer is going to surpass heart disease as the number one killer in the world. The most common cancer types include lung cancer, prostate cancer, stomach cancer, colorectal cancer and breast cancer. Survival of cancer patients has been significantly improved in the past 20 years due to discovery of new treatment modalities and improvements of existing ones, according to the book "Clinical Oncology."
The four foremost treatment options for cancer are surgery, chemotherapy, radiation therapy and biological therapy.
Surgery
Surgery is the best treatment option for early-stage cancers. In many cases, surgery alone will be responsible for patient outcome, while in other cases, surgery needs to be combined with other treatment modalities to provide the best possible outcome for the patient. The fundamental principle of cancer surgery is total remove of tumors and any cancerous tissue. Surgery can be used to remove the primary tumor or metastases (cancer that has spread beyond the original site to other organs in the body).
Chemotherapy
During treatment by chemotherapy, drugs are used to kill cancer cells. Chemotherapy drugs are designed to specifically target cancer cells and stop them from growing and/or dividing.
Chemotherapy drugs have several side effects since chemotherapy drugs also cause harm to normal, healthy cells. Side effects of chemotherapy include mouth sores, low blood cell counts, fatigue, nausea, vomiting, hair loss and pain, according to the National Cancer Institute.
Chemotherapy can be used before surgery to shrink the tumor (neoadjuvant chemotherapy) or after surgery to reduce the risk of recurrence and metastatic cancer (adjuvant therapy).
Radiation Therapy
Radiation therapy is the use of high energy and focused beams to kill cancer cells. Radiation therapy causes damage to cell DNA, which eventually leads to death of cancer cells. The amount of radiation (dose) and the rate at which it is delivered are important to the effects of radiation on targeted tissues. Radiation therapy can also cause harm to normal tissues in the neighborhood of the tumor. Recent developments in computer visualization technology enables accurate planning and delivery of radiation dose and reduces damage to normal tissues, according to "Clinical Oncology."
Biological Therapy
Biological therapy (also known as immunotherapy) uses the immune system to fight cancer. The immune system is the body's defense system against disease and infection. Biological therapy uses substances called biological response modifiers (BRMs) to change the interactions between cancer cells and the immune system. This includes making cancer cells more susceptible to the immune system, boosting the power of immune system cells, blocking malignant transformation of normal cells into cancerous cells and reducing the risk of metastasis.
