Cancer: the Good, the Bad, and the Ugly
We've made great progress since President Nixon declared war on cancer 30 years ago, but can the war be won?
The Katie Couric Curve continued...
"We are picking up earlier cancers and that's making a difference, and
part of the difference is also very good chemotherapy for colon cancer," he
says. For example, it used to be that if colon cancer had spread to the liver,
"survival was nine to 11 months, but now we can resect the liver and
chemotherapy kills the microscopic disease, so we seeing survival in the range
of 50%," he tells WebMD.
Overall, "advances in cancer have been in treating the microscopic
disease," he says. "Chemotherapy for breast cancer and colon cancer has
significantly improved because we can kill the small disease that is not
visible and regrows either in the vicinity of the cancer or spreads throughout
the body." Chemotherapy can knock out errant cancer cells along with the
The rates of colorectal cancer have dropped between 1998 and 2001 in both
men and women. Prostate and female breast cancer rates have continued to
increase, although at a slower rate than in the past. However, the increase may
be due to increased detection because of higher rates of screening using
prostate specific antigen test for prostate cancer and breast X-ray or
mammography for breast cancer.
New Warriors Join Battle
New "smart" drugs are also promising weapons in this war. "This
year, there has been enormous progress in the angiogenesis inhibitors, and it
is the first year that there has been a significant increase in survival of the
three top cancers - colon, breast, and lung -- due to antiangiogenic therapies
being introduced," Folkman tells WebMD. Antiangiogenic drugs, also called
angiogenesis inhibitors, starve tumors to death by cutting off their blood
For example, Avastin targets a protein called vascular endothelial growth
factor (VEGF), which plays a role in making new blood vessels for tumors (a
process called angiogenesis). This drug was approved in the U.S. for colon
cancer in February 2004, and by January 2005 it had been approved in 27 other
countries, he says.
Other antiangiogensis drugs being used include thalidomide and Tarceva.
Tarceva blocks tumor cell growth by targeting a protein called HER1/EGFR that
is important for cell growth in advanced nonsmall cell lung cancer. Tarceva
"blocks three angiogenic proteins and really is an angiogenic
inhibitor," Folkman says. Thalidomide became notorious in the 1960s when it
was prescribed to pregnant women to ease morning sickness, but was found to
cause severe birth defects by limiting the blood flow to developing limbs. As a
result, many children were born limbless or with severely shortened limbs. Now
scientists are capitalizing on these same blood-limiting properties to help
block the blood supply to tumors.