Thursday, March 5, 2015

An Emerging Face of Cancer: Today’s Understanding



An Emerging Face of Cancer: Today’s Understanding

Case Study
Sally sat motionless with her hands gripping the steering wheel after she turned off the car in her driveway. Thirty minutes before she was meeting with her doctor to review some tests, when she heard the words that would change her life forever. The words, “You have ovarian cancer” repeated through her mind ever since the doctor spoke them. She didn’t remember much after that except looking an x-ray that showed the cancer had spread from her ovaries to several locations throughout her “abdominal area”.
Sally did not know what to do next. She had been divorced for 6 months and did not feel comfortable calling her ex-husband. Sally’s friend had offered to go to the doctor’s visit with her, but Sally never wanted to inconvenience her friends. Most had their hands full with children and elderly parents. She thought having cancer meant you received chemotherapy and likely may not survive anyway. Sally did not know what cancer was, how to live with it or what do next.

Introduction
Many years before the body is effected in anyway, a potentially catastrophic change happens. It is likely an accumulation of one or many environmental factors that trigger one gene, likely an oncogene, in one cell projecting a new aberrant genomic pattern that has the potential to destroy the human body. This is cancer.
Cells of each organ or tissue divide to grow in a controlled manner specific to that organ. This way when old or poorly functioning cells die new cells replace them. Thus providing a relatively constant mass of specialized cells needed to maintain proper function in each organ or tissue. When the genetic material of a cell (DNA) is damaged or is triggered “on”, this is considered a mutation and affects the growth and cell division rate of that cell and subsequent expanding cell line of its progeny.

Text Box: The excessive growth rate causes a mass of cancer cells, called a tumorMost commonly when a cell is damaged or has genetic malfunction, the affected cell will simply die. Cancer occurs when cells undergo a series of genetic alterations that involve a gene responsible for regulating the rate of cell growth and division to form new cells. As a result,  these new aberrant cancer cells survive longer and still new cells are made when the body does not need them or have space for them. This accumulation of extra non-functioning cells form a mass of tissue called a tumor.mage titled Loss of Normal Growth Control. The image shows normal cell division and normal cell suicide or apoptosis of a damaged cell. It also shows cancer cell division, through several mutation stages, ending in uncontrolled growth.

Cancer is a very broad term that encompasses diseases that manifest clinically as a result abnormally dividing cells that lost the ability to control their rate of growth. As a result, the cluster of cells grows to cause dysfunction in the initial organ and then continue to grow to invade other organs. The cancer cells “grow wild”, spread to adjacent tissue and some types spread throughout the body as transported by the blood stream and lymphatic system.  For example, ovarian cancer starts in the ovaries and usually spreads by into the surrounding abdominal cavity and colon by the type clinical symptoms warrant a doctors visit.

Cancer types
There are over 100 types of cancer and the organ that they started names most by the name of the apparent type of cell involved. A carcinoma is a cancer of the skin or outside ling of an internal organ.
Squamous cell carcinoma occurs most commonly along the breathing tract, mouth to lung. Squamous cells cover the majority of the respiratory tract and after years of carcinogenic irritants (smoke, chewing tobacco) a gene in one or a group of squamous cells initiates a cancer genomic process. Sarcoma is cancer of the bone, cartilage, fat, muscle, blood vessels or connective tissues.  Cancer that originates in the bone marrow, that is responsible for forming blood products (platelets, red and white blood cells), is called Leukemia. The rapid production of abnormal blood cells in leukemia take precedence over production of the critical production of healthy blood cells the body desperately depends on. Lymphoma and myeloma are cancers of the immune system. The cancers of the brain and spinal cord are unique because the cell types primarily exist in the brain. For example, an astrocytoma originates for the abnormal reproduction of astrocytes, which are only present in the brain.

Behavior of a tumor
A tumor or cancer cells are usually not detected until they cause enough interference to prevent one or more organs to function appropriately. For example, the ovary has space to grow significantly before it interferes with function of other abdominal organs. However, the local invasion of cells into the abdominal cavity results in fluid secretion and accumulation where the weight of fluid is not normally present, creating discomfort. In addition, the “aggressive” cell type of some ovarian cancers rapidity invades the colon and produce gastrointestinal symptoms of bleeding, obstruction or diarrhea. T cell leukemia uses most bone marrow supplies to produce abnormal T cell’s (one type of white blood cell) that there is enough to produce red blood cells or platelets.

Prevalence of Cancer
Cancer continues to be a major health problem throughout the world. In In the U.S., cancer accounts for approximately 25% of all deaths that occur each year. Between 2006-2010 over 1.5 million Americans were diagnosed with cancer. With over one-third of those dying form a  cancer related cause.  (http://onlinelibrary.wiley.com.ezproxy.med.nyu.edu/doi/10.3322/caac.21208/pdf)
Although grim, these statistics reflect small improvements. Over the past 5 years cancer related death rates have decreased by about 1.5%. The incidence or cancer has decreased 0.6% in men and has remained unchanged in woman. The death rate from cancer peaked in 1991 and has been slowing since that time. The largest decline (55%) occurred in black men aged 40-49 years.

Text Box: Most Common Cancer Types
Men
Prostate  27%
Lung         14%
Bladder     7%
Melanoma of skin 5%
Women
Breast     29%
Lung         13%
Uterine    6%
Thyroid   6%
https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcS3zPTmdMDARG4mTJZbjqR9actfg4polnNI2sx6-35pBht7qi2c

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