Life's Delicate Balance
Causes and Prevention of Breast Cancer
by Janette D. Sherman, M.D.

Excerpts from Chapter 2
The Delicate Balance of Life
How cancer grows

"That life will never come again 
Is what makes life so sweet."
    Emily Dickinson, poem no. 1741  

Life is both hardy and delicate at the same time. Damage to the genetic machinery of individual cells can trigger a series of miscalculations, altering a cell's normal function. When a gene is damaged by radiation or chemicals, or receives misinformation from a chemical messenger, and the mistaken signal is not corrected, the result is inappropriate or uncontrolled growth. This is the basis of cancer.

Cancer develops in healthy people. Cancer strikes children and adults alike. Cancer is life uncontrolled and occurs when a chemical cascade is set in motion that is difficult-to-impossible to reverse.

...

Life is both hardy and delicate at the same time.  Damage to the genetic machinery of individual cells can trigger a series of miscalculations, altering a cell's normal function.   When a gene is damaged by radiation or chemicals, or receives misinformation from a chemical messenger, and the mistaken signal is not corrected, the result is inappropriate or uncontrolled growth. This is the basis of cancer.

Cancer develops in healthy people.  Cancer strikes children and adults alike.  Cancer is life uncontrolled and occurs when a chemical cascade is set in motion that is difficult-to-impossible to reverse.

Following various steps along the way, from normal to frankly abnormal cells provides understanding of the cancer process.  Cells can be studied under the microscope and tested with biological techniques.  These studies show that neoplasia, literally "new growth" proceeds in a sequential fashion.  That is, increase in the number of cells (proliferation); increase in size of each cell (hyperplasia); change in the basic structure (metaplasia); to frank tumor growth.  Tumors may be either benign or malignant (cancerous), and each can spread locally and/or to distant sites.

...

Life is both hardy and delicate at the same time. Damage to the genetic machinery of individual cells can trigger a series of miscalculations, altering a cell's normal function. When a gene is damaged by radiation or chemicals, or receives misinformation from a chemical messenger, and the mistaken signal is not corrected, the result is inappropriate or uncontrolled growth. This is the basis of cancer. 
Cancer develops in healthy people. Cancer strikes children and adults alike. Cancer is life uncontrolled and occurs when a chemical cascade is set in motion that is difficult-to-impossible to reverse. 

Following various steps along the way, from normal to frankly abnormal cells provides understanding of the cancer process. Cells can be studied under the microscope and tested with biological techniques. These studies show that neoplasia, literally "new growth" proceeds in a sequential fashion. That is, increase in the number of cells (proliferation); increase in size of each cell (hyperplasia); change in the basic structure (metaplasia); to frank tumor growth. Tumors may be either benign or malignant (cancerous), and each can spread locally and/or to distant sites.

cell proliferation
hyperplasia
metaplasia
tumor formation
benign
malignant
local spread
metastases

These same uncontrolled processes occur throughout the living world: in humans, fish, turtles, birds, cattle, cats, dogs, even plants. All living creatures can develop the uncontrolled growth we call cancer. No life is exempt from cancer. Claims have been made that sharks don't develop cancer, but alas, they too succumb to cancer. To learn more about this, I visited the laboratory of Dr. John Harshbarger, Director of the Tumor Registry in Lower Animals for the Smithsonian and now at George Washington University. Dr. Harshbarger showed me tumors taken from sharks, benign and malignant, and from various organs. He explained that cancer development in these animals was a function of where the sharks had lived, in clean or polluted waters. 

Alteration of the kind, sequence, or arrangement of DNA's components can change irreversibly the function and growth of a person, animal or plant. Alterations in reproductive cells, the sperm or the egg, may be transmitted to the offspring, changing the life of that off-spring, expressed as functional or physical defects, and with the potential to be transmitted to future generations. Defects in an offspring results from damage to the germ cells or to the embryo/ fetus as it is developing. 

Alterations in any of the other cells of the body, called somatic cells, may result in cancer. Cancer, the body's somatic cells gone awry, can be considered the destructive off-spring of the body's tissues. A variety of insults, chemical and radiant energy, can change the function or form of an originally normal cell, sending it on the path to malignancy.