What Is Cancer?

The Answer to Cancer
by Carolyn D. Runowicz, M.D., Sheldon H. Cherry, M.D., Dianne Partie Lange

This urgent, hopeful new book explores the cutting edge in the war against cancer - with exclusive coverage of the most exciting discovery of all: chemopreventive drugs that can actually stop the cancer process from starting.

The landmark announcement that tamoxifem could protect against breast cancer in high-risk women signaled the dawn of a new era in the battle against cancer. Now two hightly respected physicians, one of them a cancer survivor, report on dramatic breakthroughs in cancer prevention. Whether the goal is to prevent a recurrence, people will turn to this book for news they can use, such as:

• Provides the latest information on the new chemopreventive drugs
• Identifies key lifestyle factors that can influence cancer risk
• Evaluates the effectiveness of popular anti-cancer measures
• Helps readers to conduct their own personal risk assessment

Evidence that we can prevent cancer through early intervention is so strong that the National Cancer Institute is currently sponsoring 80 chemoprevention trials. With the new information in this book, we have reason to hope that we are winning the war against this dreaded disease.

Chapter 1

Every cell in the body is programmed to perform a certain job, depending on which organ it is part of. With the exception of brain and nerve cells, the rest continually develop, divide, die, and are replaced with newly formed cells.

It's believed that cells replicate a finite number of times, though just what determines their life spans remains a mystery. In any event, if the genetic machinery that directs a cell's division to proceed on a predetermined schedule goes awry, the cell may continue growing, and at a faster rate than normal. Similarly, a cell that experiences a malfunction in its genetic program to self-destruct may keep dividing indefinitely, rather than dying.

Nobel prize-winning scientist H. Robert Horvitz, Ph.D., an expert in the genetic intricacies of normal cell death, succinctly describes cancer as a change in the equilibrium between cell division or growth and cell death. "If you have too much cell division, you get an increase in cell number; if you have too little cell death, you also get an increase in cell number," Dr. Horvitz explains. "Either can lead to cancer."

Cells divide too often or refuse to die because of a genetic error, and usually more than one. Fortunately, the body has the ability to protect itself against a cell that contains flawed genetic messages. For instance, natural killer cells-which are components of a healthy immune system-will detect and eliminate a mutated, misbehaving cell. But sometimes the body's search-and-destroy mechanisms fail, and a malformed cell continues to divide, generating more and more copies of itself.

Although these renegade cells differ slightly from one another, they tend to cluster together, forming a mass or tumor. On the whole, they're an aggressive bunch, bullying and pushing their way into healthy tissues. Eventually a tumor can become so large that the affected organ can't do its job. Or a tumor may press on neighboring structures, obstructing some vital function or causing pain.

What's more, tentacles of the cancer cells can extend from the tumor into adjacent tissues, as well as into blood and lymph vessels. Sometimes the cells break free and spread through these circulating channels to distant organs, where they form more clusters of abnormal cells and a secondary cancer. This spreading process is known as metastasis.

The further cancer progresses, the less likely it is to be stopped. Once it has spread, or metastasized, to other parts of the body, successful treatment becomes very difficult.

Not All Cancers Are Alike

The progression from that first cluster of abnormal cells to a detectable tumor may take years. Cancer cells, being outsiders, follow no rules. They don't grow steadily and smoothly in a coordinate way, like healthy cells with flawless genetic messages. Instead, they tend to rest and grow, rest and grow.

But some cancers, when they are in a growth stage, can become quite large quite fast. They develop and spread so quickly that they may not be discovered until they are so large that they produce life-threatening symptoms.

Even a single form of cancer can manifest many different ways. For instance, one man may have prostate cancer all his life, but it grows so slowly that it doesn't produce symptoms and never spreads beyond his prostate gland, where it began. In fact, his cancer may remain undetected until he dies from some other cause. Another man may learn that he has advanced prostate cancer less than a year after a normal screening test. Ultimately, he may die from the disease.

Whether they grow quickly or slowly, not all tumors can be felt. If one is buried deep within the chest or abdomen, for instance, a person will have no clue that it's there unless it begins to interfere with some vital function or produces symptoms.

Fortunately, researchers have developed screening tests to find these hidden cancers before they reach advanced stages, as well as to detect abnormalities before they become full-fledged cancers. They're called screening tests because they're performed on healthy people who have no symptoms, for the sole purpose of looking for cancer or a condition that could lead to cancer. Screening tests that detect precancerous conditions are an essential part of cancer prevention. We will discuss tests that doctors now use, and those that researchers still are perfecting, throughout this book.

Recognizing the Enemy

It has been said that cancer is more than 100 different diseases because it varies according to the type of cell that's involved and the organ that is home to those cells. Despite this inherent diversity, all cancers share four fundamental characteristics.

1. CANCER BEGINS WITH THE BODY'S OWN CELLS. The cause-that is, whatever alters the genetic message within a cell- may come from outside the body. But the tumor itself is a cluster of cells.

2. THE CELLS GROW OUT OF CONTROL AND DON'T DIE. If a cancer is not detected and removed-or if its growth is not stopped with chemotherapy or radiation therapy-the cells will continue to divide.

3. THE CELLS FROM THE TUMOR MAY EXTEND INTO SURROUNDING TISSUES AND ORGANS, OFTEN DESTROYING THEM IN THE PROCESS. Even if this occurs, a cancer may not be fatal. The key is to excise all or part of the affected tissue, removing any trace of cancer cells. As extra insurance, this surgery often is followed by chemotherapy or radiation therapy to kill any cells that may have escaped detection.

Later in the book, you'll learn how some drugs can help prevent a recurrence of cancer when taken after treatment for the disease. Doctors refer to this as chemoprevention. They use the same term to describe drugs that stop the development of cancer in the first place.

4. THE CELLS CAN TRAVEL FAR FROM THE ORIGINAL TUMOR. Eventually, cancer cells enter the circulatory and lymphatic systems. From there, they spread to other areas of the body and begin to grow at those distant sites.

Because some 200 different kinds of cells exist in the body, doctors identify cancers according to the cells from which they originate. Every cell falls into one of four general categories:

• Epithelial cells, which comprise skin and line the passageways of the breasts, lungs, stomach, intestine, bladder, ovaries, uterus, and prostate

• Connective tissue cells, such as those that form cartilage, bone, muscle, and blood vessels

• Blood-forming cells, which make up the bone marrow

• Nerve cells, which include those in the brain and the body

Let's suppose that a doctor diagnoses a patient with epithelial carcinoma. In layperson's language, this means a cancer that involves the epithelial cells. Doctors also may describe tumors according to the function of the cells. For instance, an adenocarcinoma arises from secreting glands, such as those that form in the breasts from epithelial tissue.

Tests are available to determine the aggressiveness of a particular cancer, as well as appropriate treatment options. Although these tests are important, they can be done only after a cancer has been discovered. Researchers are working to identify markers that alert doctors to the presence of a cancer or precancer that consists of just a few cells. Then, even if the cancer is aggressive, the cells can be removed or destroyed before a tumor develops.

A good example of this type of test is the Papanicolaou smear, or Pap test, which has been in use since the 1950s. This routine screening test for women detects abnormal cells on the cervix that are likely to become malignant. More recently, researchers have been working on tests to examine breast fluid for cancer cells, and stool samples for abnormal cells from the colon lining. The tests are under evaluation to determine their accuracy in discovering precancerous conditions and their practicality for widespread clinical use.

© 2004 by Carolyn D. Runowicz, M.D. and Sheldon H. Cherry, M.D.

About the Author

Carolyn D. Runowicz, M.D., currently serves as directory of the University of Connecticut Cancer Center in Farmington. She is second vice president of American Cancer Society and past president of the Society of Gynecologic Oncologists, the woman to hold the post.

Sheldon H. Cherry, M.D., is clinical professor of obstetrics and gynecology at Mount Sinai School of Medicine in New York City.

Dianne Partie Lange, is the former editor-in-chief of Natural Health magazine and a former syndicated health news columnist for the Los Angeles Times. She resides in Carnelian Bay, California.