Cancer is an abnormal growth of cells, usually derived from a single abnormal cell. The cells lose their control mechanism and begin to multiply. They may invade nearby tissues, migrate to distant parts of the body, and promote the growth of new blood vessels from which the cells derive nutrients. Cancerous (malignant) cells can develop from any tissue within the body.
As cancerous cells grow and multiply, they form a mass of cancerous tissue – called a tumor – that invades and destroys normal adjacent tissues. The term tumor refers to abnormal growth or mass. Tumors can be cancerous or noncancerous. Cancerous cells from the primary (initial) site can spread throughout the body (metastasize).
Cells are the basic units that make up the human body. Cells grow and divide to make new cells as the body needs them. Normally, cells die when they get old or damaged and are replaced by new cells.
Cancer begins when genetic changes interfere with this orderly process. Cells start growing uncontrollably. These cells may form a mass called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread.
Some types of cancer do not form a tumor. These include leukemias, most types of lymphoma, and myeloma.
Cancerous tissues (malignancies) can be divided into those of the blood and blood-forming tissues (leukemias and lymphomas) and “solid” tumors (a solid mass of cells), often termed cancer. Cancerous solid tumors can be carcinomas or sarcomas. Specific cancers can be further categorized by the organ in which they first develop and the type of cell in which they arise.
Carcinomas: Carcinoma begins in the skin or the tissue that covers the surface of internal organs and glands. Carcinomas usually form solid tumors. They are the most common type of cancer. Examples of carcinomas include skin, lungs, colon, stomach, prostate, breast, lung, and thyroid gland. Carcinomas occur more often in older people.
Sarcomas: Sarcoma begins in the tissues that support and connect the body. A sarcoma can develop in fat, muscles, nerves, tendons, joints, blood vessels, lymph vessels, cartilage, or bone. Examples of sarcomas are leiomyosarcoma (cancer of smooth muscle that is found in the wall of digestive organs) and osteosarcoma (bone cancer). Sarcomas occur more often in younger people.
Leukemias: Leukemia is a cancer of the blood. Leukemia begins when healthy blood cells change and grow uncontrollably. It arises from blood-forming cells and crowd out the production of normal blood cells in the bone marrow. The 4 main types of leukemia are acute lymphocytic leukemia, chronic lymphocytic leukemia, acute myeloid leukemia, and chronic myeloid leukemia.
Lymphomas: Lymphoma is cancer that begins in the lymphatic system. The lymphatic system is a network of vessels and glands that help fight infection. Cancer cells from lymphomas expand lymph nodes, producing large masses in the armpit, groin, abdomen, or chest. There are 2 main types of lymphomas: Hodgkin lymphoma and non-Hodgkin lymphoma.
There are many other types of cancer. Consult your oncologist for more details.
As a cancerous tumor grows, the bloodstream or lymphatic system may carry cancer cells to other parts of the body. During this process, the cancer cells grow and may develop into new tumors. This is known as metastasis.
One of the first places cancer often spreads is to the lymph nodes. Lymph nodes are tiny, bean-shaped organs that help fight infection. They are located in clusters in different parts of the body, such as the neck, groin area, and under the arms.
Cancer may also spread through the bloodstream to distant parts of the body. These parts may include the bones, liver, lungs, or brain. Even if cancer spreads, it is still named for the area where it began. For example, if breast cancer spreads to the lungs, it is called metastatic breast cancer, not lung cancer.
A diagnosis begins when a person visits a doctor regarding an unusual symptom. The doctor will enquire about the patient’s history and symptoms. Then the doctor will perform various tests to find out the cause of these symptoms.
But many people with cancer have no symptoms. For these people, cancer is diagnosed during a medical test for another issue or condition.
Sometimes a doctor finds cancer after a screening test in an otherwise healthy person. Examples of screening tests include colonoscopy, mammography, and a Pap test. A person may need more tests to confirm or disprove the result of the screening test.
The type of treatment given to a patient depends on the type of cancer and its stage.
Immunotherapy to Treat Cancer
Immunotherapy is a type of cancer treatment that helps the immune system fight cancer.
Targeted therapy is a cancer treatment that targets the changes in cancer cells that help them grow, divide, and spread.
Hormone therapy is a treatment that slows or stops the growth of breast and prostate cancers that use hormones to grow.
Stem cell transplants are procedures that restore blood-forming stem cells in cancer patients who have had theirs destroyed by very high doses of chemotherapy or radiation therapy.
Precision medicine helps doctors select treatments that are most likely to help patients based on a genetic understanding of their disease.
Immunotherapy is a type of cancer treatment that helps the immune system fight cancer.
Biomarker Testing for Cancer Treatment:
Biomarker testing is a method to look for genes, proteins, and other substances (called biomarkers or tumor markers) that can provide information about cancer. Biomarker testing can help in deciding the cancer treatment.
The cancer is removed from the body through surgery. Surgery often requires cutting through the skin, muscles, and sometimes bone. After the surgery, the cuts can be painful and take some time to recover.
In open surgery, the surgeon makes one large incision to extract the tumor, some healthy tissue, and maybe some nearby lymph nodes. These tissues are checked to see if cancer has spread. Comprehending if the nearby tissue contains cancer will help the doctors suggest the best treatment plan after surgery.
In minimally invasive surgery, the surgeon makes a few small cuts instead of a large one. A long, thin tube is inserted with a tiny camera into one of the small cuts. This tube is called a laparoscope. The camera projects images from the inside onto a monitor, which enables the surgeon to perform the surgery. Special surgery tools are inserted through the other small cuts to remove the tumor and some healthy tissue.
Since minimally invasive surgery requires smaller cuts, it takes less time to recover compared to open surgery.
How surgery Helps with Cancer Treatment:
Depending on your type of cancer and its stage, surgery can be used to:
Radiation therapy is a cancer treatment to kill cancer cells and shrink tumors. Radiotherapy involves giving high doses of radiation to kill or slow down the growth of cancer cells by damaging their DNA. Cancer cells whose DNA is damaged beyond repair stop dividing or die. When the damaged cells die, they are broken down and removed by the body.
Radiation therapy does not kill the cancer cells right away. Weeks of treatment is required to cause enough damage for the cells to die.
The type of radiation therapy depends on factors like type, size, location of the tumor, and other medical considerations.
External beam radiation therapy is given from a machine that aims radiation at cancer. It is a local treatment and is meant to treat a specific part of your body. It does not touch the patient but can move around to send radiation to the part of the body from many directions.
Internal radiation therapy is a treatment in which the source of radiation is put inside the patient’s body. The radiation source can be solid or liquid and is placed in or near the tumor to give off radiation for a while.
Radiation not only kills or slows the growth of cancer cells, but it can also affect nearby healthy cells. Damage to healthy cells can cause some side effects.
Chemotherapy uses drugs to kill cancer cells. It works by stopping or slowing the growth of cancer cells, which grow and divide quickly. Chemotherapy is used to
In combination with other treatments, chemotherapy can:
Cancer can cause many different symptoms, some subtle and some not at all subtle.
Some symptoms develop early in the course of cancer, such as a painless lump in the breast, and are therefore important warning signs that should be evaluated by a doctor. Other symptoms, such as weight loss or fever, develop only after cancer progresses. Other symptoms, such as a change in bowel habits, blood in the stool, or swallowing difficulty, are signs of cancer in specific sites of the body.
Some of the warning signs are general. That is, they are vague changes that do not help pinpoint any particular cancer. Still, their presence can help direct doctors to proceed with physical examinations and laboratory tests necessary, to exclude or confirm a diagnosis. Other symptoms are much more specific and steer doctors to a particular kind of cancer or location.
If you notice any of these symptoms you must consult an oncologist at the earliest.