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what is cancer

What is cancer?

Cancer is the uncontrolled growth of abnormal cells in the body. Cancer develops when the body’s normal control mechanism stops working. Old cells do not die and instead grow out of control, forming new, abnormal cells. These extra cells may form a mass of tissue, called a tumor. Some cancers, such as leukemia, do not form tumors.

What are the most common forms of cancer?

Cancer may occur anywhere in the body. In women, breast cancer is one of the most common. In men, it’s prostate cancer. Lung cancer and colorectal cancer affect both men and women in high numbers.

There are five main categories of cancer:

  • Carcinomas begin in the skin or tissues that line the internal organs.
  • Sarcomas develop in the bone, cartilage, fat, muscle or other connective tissues.
  • Leukemia begins in the blood and bone marrow.
  • Lymphomas start in the immune system.
  • Central nervous system cancers develop in the brain and spinal cord.

How is cancer treated?

Treatment options depend on the type of cancer, its stage, if the cancer has spread and your general health. The goal of treatment is to kill as many cancerous cells while reducing damage to normal cells nearby. Advances in technology make this possible.

The three main treatments are:

 The same cancer type in one individual is very different from that cancer in another individual. Within a single type of cancer, such as breast cancer, researchers are discovering subtypes that each requires a different treatment approach.

What is oncology?

The branch of medicine dedicated to diagnosing, treating and researching cancer is known as oncology, while a physician who works in the field is called an oncologist. Some oncologists focus solely on particular cancer types or treatments. Depending on the type, stage and location of a cancer, multiple oncology specialists may be involved in a patient’s care. The field of oncology has three main specialties—medical, surgical and radiation—and numerous sub-specialties.

A medical oncologist is a licensed physician (typically in internal medicine) trained in diagnosing, staging and treating cancer. This specialist also leads the development of the cancer patient’s treatment plan, which may include surgery, chemotherapy, immunotherapy, targeted therapy or hormone therapy, while also coordinating with other oncology specialists and clinicians who may have a role in the patient’s care. A medical oncologist is also the doctor a cancer patient will continue to see after treatment, for checkups over the long-term.

A surgical oncologist is a surgeon who specializes in performing biopsies and removing cancerous tumors and surrounding tissue, as well as other cancer-related operations.

A radiation oncologist specializes in treating cancer with radiation therapy to shrink or destroy cancer cells or to ease cancer-related symptoms.

Many cancer types are treated by an oncology sub-specialty. Gynecologic oncologists, for example, are trained to treat cancers of the female reproductive system such as those affecting the uterus, cervix, or ovaries, while hematologic oncologists specialize in diagnosing and treating blood cancers (leukemia, lymphoma and multiple myeloma). A neuro-oncologist treats cancers of the brain, spine and peripheral nerves.

What can you do to manage the side effects of cancer treatment?

Supportive care services describe a broad range of therapies designed to combat side effects and maintain well-being. Treating cancer requires focusing on more than the disease alone; it must also address the pain, fatigue, depression and other side effects that come with it.

Supportive care services include:

What does the future hold for cancer treatment?

The future of cancer treatment lies in providing patients with an even greater level of personalization. Doctors are beginning to offer treatment options based on the genetic changes occurring in a specific tumor.

An innovative new diagnostic tool, the genomic tumor assessment, examines a patient’s tumor genetically to identify the mechanism that caused the cancer. Genomic tumor assessment may result in a more personalized approach to cancer treatment.

Many people are living with cancer

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