JOURNAL What is cancer? How do
cancer cells differ from other cells?
Do you know of any types of cancer? If so…name them.
REVIEW! Cells divide only when they receive the
proper signals from growth factors that circulate in the bloodstream or from a cell they directly contact.
For example, if a person loses blood, a growth factor called erythropoietin which is produced in the kidneys circulates in the bloodstream and tells the bone marrow to manufacture more blood cells.
When a cell receives the message to divide, it goes through the cell cycle which includes several phases for the division to be completed. Checkpoints along each step of the process make sure that everything goes the way it should.
Many processes are involved in cell reproduction and all these processes have to take place correctly for a cell to divide properly. If anything goes wrong during this complicated process, a cell may become cancerous.
CANCER Uncontrolled Cell Growth
A disorder in which body cells lose the ability to control cell growth.
CANCER CELLS Cancer cells do not respond to the signals
that regulate the growth of most cells. As a result, the cells divide uncontrollably.
Cancer cells---Cells that grow out of control
Ignore signals to stop dividing, to specialize, or to die and be shed
Have defects in normal cellular functions
Growing in an uncontrollable manner and unable to recognize its own natural boundary, the cancer cells may spread to areas of the body where they do not belong. In a cancer cell, several genes change (mutate) and the cell becomes defective.
WHAT IS A TUMOR?
Cancer cells divide uncontrollably to form a mass of cells called a tumor.
WHAT CAUSES CANCER?
Cancers are caused by defects in genes that regulate cell growth and division.
Some sources of gene defects are smoking tobacco, radiation exposure, defective genes, and viral infection.
METASTASIZE To transmit microorganisms or cancerous cells from an original site to one or more sites elsewhere in the body
A damaged or defective p53 gene is common in cancer cells. It causes cells to lose the information needed to respond to growth signals.
TREATMENT
Treatment will vary depending on many different factors associated with both the type of cancer & the patient. Some localized tumors can be removed by surgery.
Many tumors can be treated with targeted radiation.
Chemotherapy is the use of compounds that kill or slow the growth of cancer cells.
BENIGN Tumors that do not grow in an
unlimited, aggressive manner, do not invade surrounding tissue, and does not metastasize
A benign tumor is noncancerous. It does not spread to surrounding healthy tissue.
MALIGNANT Not self-limited in its growth and is
capable of invading into adjacent tissues
A malignant tumor is cancerous. It invades and destroys surrounding healthy tissue and can spread to other parts of the body.
May be capable of spreading to distant tissues
METASTASIS To transmit cancerous cells from an original site to one or more sites elsewhere in the body
TYPES OF CANCER
OSTEOSARCOMA Most common type of bone cancer
Affects 2x as many guys as girls
Tends to show up in people who are taller than average
LEUKEMIA One of the most common childhood cancers
Occurs when large numbers of abnormal white blood cells called leukemic blasts fill the bone marrow & sometimes the blood stream
Because these abnormal blood cells are defective, they don't help protect the body against infection the way normal white blood cells do.
And because they grow uncontrollably, they take over the bone marrow and interfere with the body's production of other important types of cells in the bloodstream, like red blood cells (which carry oxygen) and platelets (which help blood to clot).
BRAIN TUMORS No one knows the exact cause
If it is possible to remove a tumor, surgery is usually performed, followed by radiation. Some patients receive chemotherapy as well.
Survival depends on type, location & treatment
LYMPHOMA Cancer that develops in the
lymphatic system (the lymph nodes, thymus, spleen, adenoids, tonsils, and bone marrow.)
Most teens with lymphoma have either: Hodgkin’s disease or Non-Hodgkin’s lymphoma
HODGKIN’S DISEASE Occurs in adolescent and young
adults
Shows up in lymph nodes in neck, armpits etc.
Lymph nodes are usually enlarged but not painful
NON-HODGKIN’S LYMPHOMA
Similar to leukemia because both might involve malignant lymphocytes (white blood cells ) and symptoms are similar
SKIN CANCER
BASAL CELL CARCINOMA
Most common cancer in humans
Appears as a shiny translucent or pearly nodule
Most appear on skin with a history of exposure to the sun
SQUAMOUS CELL CARCINOMA
Begins in the squamous cells
Tends to develop in fair-skinned middle-aged & elderly people who have had long term sun exposure
MELANOMA Begins in cells within the epidermis that give skin its color
Most lethal form of skin cancer
BREAST CANCER Cancer that starts in the cells of the breast in men & women
LUNG CANCER A disease of uncontrolled cell
growth in tissues of the lung
Most common symptoms are: shortness of breath, coughing, and weight loss
the most common cause of cancer-related death in men and the second most common in women, is responsible for 1.3 million deaths worldwide annually.
PROSTATE CANCER A disease in which cancer
develops in the prostate, a glad in the male reproductive system. These cells may spread (metastasize) from the prostate to other parts of the body, especially the bones and lymph nodes.
Most frequently in men over 50
Many men who develop this cancer never have symptoms, undergo no therapy, and eventually die of other causes
COLON CANCER Cancer of the large intestine (colon), the lower part of your digestive system