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Cancer cells are everything we would like healthy cells to be: They
quickly adapt to toxic environments, they readily alter themselves to
assure their continued survival, and they utilize biologic mechanisms
to promote cellular immortality. All of these factors make cancer an
extremely difficult disease to treat.
Chemotherapy drugs have a high rate of failure because they usually
kill only specific types of cancer cells within a tumor or the cancer
cells mutate and become resistant to the chemotherapy. Cancer
chemotherapy could save more lives if the latest scientific findings
were incorporated into clinical medicine.
What concerns us is that respected cancer journals are publishing
articles that identify safer and more effective treatment regimens, yet
few oncologists are incorporating these synergistic methods into their
clinical practice. Cancer patients often suffer through chemotherapy
sessions that do not integrate the latest scientific findings. Our
objective is to provide the patient with more options to discuss with
their oncologist and to bring about multimodality approaches to improve
the probability of a successful outcome.
It is impossible to design a single chemotherapy protocol that is
effective against all types of cancer. The oncologist might need to
administer several chemotherapy drugs at varying doses because tumor
cells express survival factors with a wide degree of individual cell
variability. This protocol conveys the findings from published
scientific studies so that a cancer patient will have a logical basis
to augment the effects of chemotherapy and also reduce the potential
for side effects.
How Does Chemotherapy Work? According
to the National Cancer Institute, almost all normal cells grow and die
in a controlled way through a process called apoptosis. Cancer cells,
on the other hand, keep dividing and forming more cells without a
control mechanism to induce normal apoptosis.
Anticancer drugs destroy cancer cells by stopping them from growing
or dividing at one or more points in their growth cycle. Chemotherapy
may consist of one or several cytotoxic drugs that kill cells by one or
more mechanisms. The chemotherapy regimen chosen by most conventional
oncologists is based on the type of cancer being treated. As you will
read later in this protocol, there are factors other than the type of
cancer that can be used to determine the ideal chemotherapy drugs that
should be used to treat an individual patient.
The goal of chemotherapy is to shrink primary tumors, slow the tumor
growth, and kill cancer cells that may have spread (metastasized) to
other parts of the body from the original, primary tumor. However,
chemotherapy kills both cancer cells and healthy normal cells.
Oncologists try to minimize damage to normal cells and to enhance the
cell killing (cytotoxic) effect on cancer cells. Too often,
unfortunately, this delicate balance is not achieved.
Clinical studies show that for certain types of cancer chemotherapy
prolongs survival and increases the percentage of patients achieving a
remission. A partial remission is defined as 50% or greater reduction
in the measurable parameters of tumor growth as may be found on
physical examination, radiologic study, or by biomarker levels from a
blood or urine test. A complete remission is defined as complete
disappearance of all such manifestations of disease. The goal of all
oncologists is to strive for a complete remission that lasts a long
time--a durable complete remission, or CR. Unfortunately, the vast
majority of remissions that are achieved are partial remissions. Too
often, these are measured in weeks to months and not in years. Some
types of cancer do not show any meaningful response to chemotherapy.
CHOOSING THE BEST CHEMOTHERAPY DRUGS TO KILL YOUR TUMOR
It is highly desirable to know what drugs are effective against your
particular cancer cells before these toxic agents are systemically
administered to your body. A company called Rational Therapeutics,
Inc., performs chemosensitivity tests on living specimens of your
cancer cells to determine the optimal combination of chemotherapy drugs.
Dr. Robert Nagourney, a prominent hematologist/oncologist, founded
Rational Therapeutics, Inc., in 1993. Rational Therapeutics pioneers
cancer therapies that are specifically tailored for each individual
patient. They are a leader in individualized cancer strategies. With no
economic ties to outside healthcare organizations, recommendations are
made without financial or scientific prejudice.
Rational Therapeutics develops and provides cancer therapy
recommendations that have been designed scientifically for each
patient. Following the collection of living cancer cells obtained at
the time of biopsy or surgery, Rational Therapeutics performs an
Ex-Vivo Apoptotic (EVA) assay on your tumor sample to measure drug
activity (sensitivity and resistance). This will determine exactly
which drug(s) will be most effective for you. They then make a
treatment recommendation. The treatment program developed through this
approach is known as assay-directed therapy.
At present, medical oncologists, according to fixed schedules,
prescribe chemotherapy. These schedules are standardized drug regimens
that correspond to specific cancers by type or diagnosis. These
schedules, developed over many years of clinical trials, assign
patients to the drugs for which they have the greatest statistical
probability of response.
Patients with cancers that exhibit multidrug resistance will likely
receive treatments that are wrong for them. A failed attempt at
chemotherapy is detrimental to the physical and emotional well being of
patients, is financially burdensome, and may preclude further effective
therapies.
Rational Therapeutics' EVA assay uses your living tumor cells to
determine which drug or drug combination induces apoptosis in the
laboratory. Each patient is highly individualized with regard to
sensitivity to chemotherapy drugs. A patient's responsiveness to
chemotherapy is as unique as their fingerprints.
Rational Therapeutics, leading the way in custom-tailored,
assay-directed therapy, provides personal cancer strategies based on
the tumor response in the laboratory. This eliminates much of the
guesswork prior to the patient undergoing the potentially toxic side
effects of chemotherapy regimens that could prove to be of little value
against their cancer. Rational Therapeutics may be contacted at:
Rational Therapeutics, Inc. 750 East 29th Street Long Beach, CA 90806 Telephone: (562) 989-6455; Fax: (562) 989-8160 Web site: www.rationaltherapeutics.com
In addition to the EVA chemosensitivity testing, we advocate
immunohistochemistry testing of your tumor to provide additional data
that will assist in making treatment decisions. The importance of the
immunohistochemistry test is described in the Cancer Treatment: The Critical Factors
protocol. The immunohistochemistry test can be done if your physician
sends a specimen of your tumor to a specialty laboratory called Impath
(www.impath.com). Impath can be reached by calling (800) 447-5816.
Impath also performs chemosensitivity testing of living tumors (fresh
specimens). Because many chemotherapy patients' primary tumors were
previously removed or irradiated, Impath can perform the
immunohistochemistry test with a frozen or parraffin-preserved tissue
sample that is accessible through the pathology laboratory that
examined your previous tumor(s).
Protecting Against Anemia The
importance of maintaining or enhancing the oxygen-carrying capacity of
blood cannot be overemphasized. Blood oxygen-carrying capacity may be
the single most important factor in determining whether chemotherapy is
successful.
In response to a low-oxygen environment, cancer cells send out
growth signals that result in increased angiogenesis (blood vessel
growth into the tumor). Oxygen deprivation not only induces
angiogenesis, but also causes cancer cells to express additional
survival factors that make them highly resistant to the toxic effects
of chemotherapy.
It is an established fact that a low-oxygen environment (hypoxia)
promotes tumor growth. If nothing else in this protocol is followed,
correcting a hypoxic state could vastly enhance the odds of long-term
survival.
The first step in correcting hypoxia is to guard against anemia.
Anemia is common in cancer patients, and the result is that less oxygen
is delivered to the tumor, that is, hypoxia occurs. The importance of
avoiding anemia is well established in scientific literature. A study
was conducted to systematically review and obtain an estimate of the
effect of anemia on the survival of cancer patients. This study found
that the increased risk of mortality in cancer patients who were anemic
was an astounding 65% (Caro et al. 2001)!
Chemotherapy often induces anemia that then exacerbates hypoxia in
the tumor. The best way of evaluating blood oxygen-carrying capacity is
to measure hematocrit and hemoglobin levels. These are standard
components of the complete blood count (CBC) test that should be
routinely performed in all cancer patients.
Since cancer cells thrive in a hypoxic environment, the cancer
patient's hematocrit and hemoglobin should be maintained in the upper
one-third of normal range prior to the initiation of chemotherapy.
Table 1 describes the optimal ranges of hematocrit and hemoglobin for
cancer patients.
| Table 1: Optimal Ranges of Cancer Patients' Hematocrit and Hemoglobin Levels |
| Based on findings from
survival studies, cancer patients should fall within the optimal ranges
of the following two blood tests that measure the oxygen-carrying
capacity of blood: |
| Blood measure |
|
Normal Laboratory Reference Range |
Optimal Range For Cancer Patients |
| Hemoglobin |
(men) |
12.5-17 grams/dL |
15.5-17 grams/dL |
| |
(women) |
11.5-15 grams/dL |
13.83-15 grams/dL |
| Hematocrit |
(men) |
36-50% |
45-50% |
| |
(women) |
34-44% |
41-44% |
| Normal reference ranges based on Labcorp's standards as of May 14, 2002. |
Hypoxia (low oxygen) promotes tumor growth by inducing angiogenesis
and causing cancer cells to express survival factors that interfere
with the ability of chemotherapy to kill them. Chemotherapy drugs are
supposed to promote apoptosis. In a hypoxic environment, however,
cancer cells develop survival mechanisms that protect them against
apoptosis.
There are nutrients that help improve anemic states, but any cancer
patient who does not have his or her hematocrit and hemoglobin in the
upper one-third of the normal range (as described in Table 1) should
consider the drug Procrit (or Epogen) to achieve such levels. Procrit
is a natural erythropoietin that stimulates the production of red blood
cells. There is also a new long-acting erythropoietin agent approved by
the FDA called Aranesp, which allows dosing every 2 weeks instead of
weekly injections.
If an oncologist fails to address anemia, the patients should assume
the role of advocate, demanding that attention be paid to the quality
of his blood counts.
A problem that cancer patients will encounter is that oncologists
normally view low blood counts as normal in cancer patients and are
reluctant to prescribe Procrit unless anemia is demonstrated. Because
Procrit is an expensive drug, most insurance companies refuse to pay
for it unless a cancer patient is severely anemic (<10g/dL).
Remember, anemia means hematocrit and hemoglobin are below the
low-normal laboratory reference ranges. A cancer patient, on the other
hand, should aim to have levels in the high upper-third range of normal
for hematocrit and hemoglobin. Some insurance companies will not pay
for Procrit until hematocrit levels are at least 20% below the lowest
normal range. Is it any wonder that chemotherapy fails for so many
cancer patients?
Since most insurance companies will not pay for Procrit for the
purpose of boosting hematocrit and hemoglobin to the upper ranges of
normal, patients may have to pay for this drug as an out-of-pocket
expense. The first hurdle is convincing the oncologist to prescribe
Procrit. The good news is that most cancer patients may only need
Procrit for a few months, so the high cost does not have to be borne
indefinitely.
The Vitamin Depot Online.com Foundation has located pharmacies that will sell
Procrit at lower prices. If your insurance company will not reimburse
for this costly drug, call (800) 544-4440 for referrals to pharmacies
that may charge less than conventional retail prices.
Inhibiting the COX-2 Enzyme Some
progressive oncologists are prescribing cyclooxygenase-2 (COX-2)
inhibitor drugs along with chemotherapy to improve the odds of
successful treatment. COX-2 is an enzyme that many types of cancers use
in order to propagate. COX-2 and its byproducts such as prostaglandin
E2 (PGE2) have been shown to help fuel the growth of cancers such as
colon, pancreas, estrogen-negative breast, prostate, bladder, and lung
cancer.
Drugs that inhibit the cyclooxygenase enzyme are known as COX-2
inhibitors. Celebrex and Vioxx are two popular COX-2 inhibitors. Both
Celebrex and Vioxx are nonsteroidal anti-inflammatory drugs (NSAIDs)
that are usually prescribed to treat the symptoms of rheumatoid
arthritis and osteoarthritis. There appears to be more research about
Celebrex in the treatment of cancer than Vioxx.
Since chemotherapy can cause gastrointestinal bleeding, careful
physician monitoring is needed when using a COX-2 inhibiting drug such
as Celebrex. Caution is urged for those with known kidney disease, poor
heart-lung function, liver disease, or susceptibility to stress-induced
ulcers. The protocol entitled Cancer Treatment: The Critical Factors
has a detailed description of the connection between COX-2 and cancer
and why inhibiting the COX-2 enzyme is so important in treating many
cancers.
In 1996, Vitamin Depot Online.com recommended that most cancer patients take a
COX-2 inhibiting drug because of solid evidence that cancer cells use
the COX-2 enzyme to sustain their rapid division. In 1996, Americans
had to import a COX-2 inhibitor named nimesulid from other countries
because this class of drug was not widely available in the United
States.
Experiments in laboratory animals suggest that drugs such as
Celebrex could help cure cancer, especially if combined with
chemotherapy or radiation (Hsueh et al. 1999; Pyo et al. 2001; Swamy et
al. 2002). There are 100 separate cancer studies involving COX-2
inhibitors going on worldwide at this time.
Doctors are predicting that COX-2 inhibiting drugs may become
standard therapy in 5-10 years. There was adequate evidence in 1996,
however, to recommend COX-2 inhibiting drugs available to cancer
patients. There are three potent COX-2 inhibiting drugs on the American
marketplace. You may ask your physician to prescribe one of the
following COX-2 inhibitors:
Lodine XL, 1000 mg once a day or Celebrex, 200-400 mg every 12 hours or Vioxx, 12.5-25 mg once a day |