What We're Learning about Cancer that Spreads
Until about five years ago, the reasons why cancer spread-and how it spread-were
little understood. The spread of cancer is called "metastasis." Metastasis
is the primary way that cancer causes death. In fact, fewer than 10 percent
of deaths from cancer are caused by the initial cancer tumor. Death usually
occurs when cancers cells travel to and take hold in such crucial areas as the
lungs, liver, bones and brain.
Without understanding how and why cancer cells metastasize, it's difficult
to develop effective treatments. But there have been recent breakthroughs that
have cast more light on the process of metastasis, which means that new treatments
are on the horizon.
How does cancer spread?
The movement of a cancer cell to a new site in the body is a complex process.
Here's how it generally works:
Cancer generally originates inside linings of organs. To spread, one cell breaks
away from this lining and moves into a capillary in the bloodstream. At this
phase, it's easy for the cell to be destroyed, either by being tossed around
by the force of the circulatory system or from an attack by white blood cells.
If the cell survives, it travels in the capillary into the tissue of a new
organ. When it's still one single cell, it's called a "micrometastasis."
At this stage, it's likely that the new organ will attack the foreign cancer
cell and kill it. But in some cases, the cell survives, and begins to divide
and grow. At this point it's called a "macrometastasis." It's now
detectable on diagnostic tests. And it's life-threatening because it impairs
the function of the organ by crowding out the normal, healthy cells.
The fact is that the success rate of metastasis is actually very low. Many
cancer cells break away from their primary tumors, but few manage eventually
to find a new environment in which to grow. If the success rate weren't so low,
there would be far more deaths due to cancer. The question is, why are some
cells successful at spreading?
New answers to old questions
Here are some of the newer angles researchers are looking at as they investigate
more and more about the metastatic process:
It's now thought that the normal cells in the organs of some people produce
enzymes that make the structure of the new organ looser and easier for tumor
cells to grow in.
Bone is one of the more common places that cancer spreads to. Normal bone
constantly goes through a cycle of breaking down and then rebuilding itself.
Now, researchers believe that if a cancer cell enters bone during the rebuilding
phase of the cycle, the cancer cell may benefit from this rebuilding environment,
and be "encouraged" to grow.
Genetics is thought to play a large role in what makes one person's organs
more receptive to tumors than another person's. Having a "tumor friendly"
genetic makeup would make someone at higher risk for metastasis. People possessing
the more tumor-friendly gene would be treated more aggressively than those who
do not have the gene.
Some researchers believe there's a sort of "master" gene that knows
how to set off the entire complex process of metastasis, and research is ongoing
in ways to stop that master gene-or genes-from starting the process in the first
Other researchers are investigating whether cancer stem cells are responsible
for metastasis. If that's the case, it could explain why so few cells-the ones
that have stem cell characteristics-are able to spread.
With such a new depth of understanding about cancer metastasis, the pharmaceutical
industry now realizes that there needs to be many different type of drugs that
can effectively treat cancer that has spread. This new understanding, combined
with a more targeted approach to treatment, offers new hope in an area that
researchers haven't felt positive about until very recently.
Source: American Institute for Cancer Research; The National Cancer Institute;
The New York Times, Scientists Begin to Grasp the Stealthy Spread of Cancer,
15 August 2006
Alternative Medicine: How Yoga Helps the Stress of Cancer
When you're being treated for cancer, the stress can be overwhelming. Even
when the treatment's over, there's often the lingering stress and worry about
whether you're going to stay healthy. For many people who've had cancer and
who have recovered from cancer, yoga can offer great stress relief.
Getting your immune system healthy is one thing you want to focus on when you're
dealing with cancer. But the stress of cancer itself can be hard on your immune
system. Yoga practice, on the other hand, can create a sense of relaxation and
well-being. Simply holding a stretch and focusing on your breath is calming
If you have cancer, it would be especially helpful to take a yoga class that's
designed for people with cancer or other illnesses. These kinds of classes are
more likely to focus on the relaxation and deep breathing aspects of yoga, not
on getting into difficult postures and holding them for as long as you can.
And if you're at a point in your cancer treatment where you feel too tired to
actually do yoga, you may get some benefit just by attending the class and listening
to the soothing words of the instructor.
Studies have shown that yoga can help with high blood pressure, breathing problems,
mood problems, stress-related disorders, pain management and a host of other
Nobody will tell you that yoga classes make tumors shrink. But taking part in
a relaxing activity may be just the thing to help you create a sense of well-being
during a challenging time in your life. And who knows-you may come to enjoy
yoga so much that you'll want to make it a lifelong practice.
K. Pelletier, The Best Alternative Medicine, Simon & Schuster, New York, New York, 2000