| TREATMENT |
TARGET |
HOW THEY WORK
|
STATUS |
| Anti- angiogenesis
Factors |
Multiple |
A growing tumor requires plenty of nutrients,
and to make sure it gets them the tumor secretes substances that
stimulate the growth of new blood vessels. A number of agents can
block this process--at least in animals. |
See chart below |
| Anti- metastatic
Factors |
Multiple |
What kills most cancer patients is not the
primary tumor but its metastatic spread. Scientists have identified
a class of enzymes that enables cancer cells to enter the
bloodstream by dissolving tissue and boring holes through capillary
walls. New drugs could keep cancer cells confined to one spot. |
Human tests have just begun |
| Anti- oncogenic
Factors |
Multiple, including breast, colon, pancreatic
and lung |
Tumors do more than pick up growth factors that
circulate in the bloodstream; they also make them by switching on
"oncogenes." Many cancers, for example, have been found to contain
mutations in the ras oncogene, and companies are racing to develop
drugs that inhibit its growth-promoting activity. |
Human tests are in early stages |
| Chemo- prevention
Therapies |
Breast, head and neck |
Many breast cancers depend on the female hormone
estrogen to stimulate their growth. Tamoxifen, which acts as an
antiestrogen in the breast, has been shown to prevent the
development of this form of cancer. Preliminary evidence suggests
that a newer compound, raloxifene, may confer a similar benefit
without serious side effects. Compounds know as retinoids,
derivatives of vitamin A, can prevent recurrence of certain head and
neck cancers. |
Tamoxifen has been approved as a treatment for
breast cancer; raloxifene, as a treatment for osteoporosis |
| Gene Therapies |
Multiple, including breast, ovarian and
small-cell lung cancers |
In tumors, genes that are supposed to serve as
checks on runaway cell growth are often so damaged that they stop
functioning. Scientists hope to correct this problem by engineering
viruses that can "infect" cancerous cells with healthy
tumor-suppressor genes. Preliminary evidence suggests that this
approach can sometimes cause tumors to stop growing and even shrink
in size. |
Testing in humans has just begun |
| Chemo- therapy |
Multiple |
New, more selective compounds and powerful but
less toxic versions of older drugs are being added to the
oncologist's arsenal. Oral and wafer formulations of injectable
drugs have made the delivery of chemotherapy more convenient for
patients. Enclosing cancer-killing toxins in a protective lipid
"envelope" can increase their effectiveness while sparing normal
tissues. |
In the past two years, the FDA has approved two
dozen new chemotherapy agents |
| Monoclonal
Antibodies |
Non-Hodgkin's lymphoma, breast, colon, melanoma
|
Like miniature guided missiles, these biological
constructs home in on specific proteins displayed on the surface of
cancer cells. By blocking strategic sites, monoclonals can interfere
with a tumor's ability to absorb growth factors from the
bloodstream. They can also carry radioactive and chemical toxins
that directly destroy malignant tissue. |
Rituxan won FDA approval last year; Bexxar and
Herceptin could be on the market within a year |
| Radiation Therapies
|
Multiple: often prostate and solid tumors in
internal organs; lymphomas |
Radiation destroys cancerous cells but can
damage healthy ones as well. Using 3-D computer images and new
delivery techniques like radiation "seed" implants, doctors can aim
doses with microscopic precision, sparing healthy tissue. |
In use |
| Surgical Procedures
|
Multiple |
Doctors are always looking for ways to make this
standard treatment more effective and less traumatic for the
patient--for example, by removing part rather than all of a breast
or preceding surgery with other treatments. One promising new
technique is lymphatic mapping, in which surgeons use dyes and
radioactive tracers to help them be more selective in removing
nodes. |
Widely available; the newest procedures are
performed at most large cancer centers |
| Vaccines |
Melanoma, breast, colon, ovarian, pancreatic and
many others |
Malignant growths have a deadly knack for
skirting around the body's immune system. But scientists are finding
that by vaccinating patients with antigens derived from tumors, they
can sometimes goad white blood cells into attacking cancerous
tissues. |
Dozens of vaccines are being tested
|
