Transcript Are We Truly winning the War On Cancer?

Introduction
Since President Richard M. Nixon
declared a “War on Cancer” in 1971, the
federal government has spent over $105
billion on cancer research efforts.
 Has the time, effort, and money spent
on this issue been worthwhile?
 The opinions on this matter vary greatly.

Introduction
Some prominent professors and
researchers have claimed that
meaningful progress has been made
against cancer.
 However, they generally only report on
the success of treating certain cancers.
 The cancers for which little or no
progress has been made in treatment
are not mentioned.
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Introduction
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Contrary to these claims of success, the
death rate of cancer victims (adjusted
for the size and age of the population)
has only dropped 5% since 1950. This
was according to an article by Gina
Kolata of The New York Times.
The Cancer Facts
The war on cancer has not been effective.
It is not decreasing as fast as other devastating ailments.
 For example, the death rate for stroke/cardiovascular
diseases have fallen by 74% and 64% respectively from
1950-2006.
 Once again, the death rate for cancer has only decreased
by 5%.
 Decrease in stroke/cardiovascular disease is due to:
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1. Methods of controlling high blood pressure
2. Use of aspirin
3. Use of beta blockers
4. Use of calcium channel blockers and ACE inhibitors
Cancer therapy is obviously decades behind
stroke/cardiovascular disease therapy.
U.S. Mortality, 2006
Rank
Cause of Death
No. of Deaths
% of All Deaths
1
Heart Diseases
631,636
26.0
2
Cancer
559,888
23.1
3
Cerebrovascular Diseases
137,119
5.7
4
Chronic Lower Respiratory
Diseases
124,583
5.1
5
Accidents (unintentional injuries)
121,599
5.0
6
Diabetes Mellitus
72,449
3.0
7
Alzheimer Disease
72,432
3.0
8
Influenza & Pneumonia
56,326
2.3
9
Nephritis
45,344
1.9
Septicemia
34,234
1.4
10
*Includes nephrotic syndrome and nephrosis
Sources: U.S. Mortality Data 2006, National Health and Statistics, Centers for Disease Control and Prevention, 2009
Methodological Issues

Detection Bias
 If a patient discovers a malignant tumor early and
starts treatment right away, even with a worthless
treatment, it appears that the patient lives longer.
 If a second patient discovers the malignant tumor
later, and starts the same worthless treatment, it is
not considered nearly as effective.
 Progression of different cancers
○ Some cancers grow very slowly, therefore the patient
may end up living longer.
○ Some cancers progress much faster, therefore
shortening the patient’s life span.
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Publication Bias
 Only positive results are published
What Do We Know About Cancer?

Example of Probable or Definite Causes of Cancer
(American Cancer Society 2009)
 External Factors
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Tobacco
Chemicals (e.g., asbestos, benzene, alcohol)
Radiation
Infections, organisms (e.g., hepatitis B, papilloma virus,
Helicobacter)
○ Hormone replacement therapy with estrogen
 Internal Factors
○ Genetic mutations
 Inherited
 Acquired
○ Hormones (e.g., estrogen)
○ Immune disorders (e.g., AIDS)
○ Epigenetic changes
○ Obesity
What Do We Know About Cancer?
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What we don’t know
 Completely unknown causal mechanism
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Diagnosis
Cancer Therapy
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Objectives of Therapy
 Prolongation of life or cure
○ Surgical removal of tumor or cure
 Improvement of quality of life
○ Chemotherapy, radiation
 Mild to severe side effects
○ Other drugs to help counteract symptoms from
treatment
 Vomiting, low white blood cell count, heart failure, nerve
damage, and diarrhea
 Value of treatment
○ Cost vs. Benefit analysis
Cancer Therapy
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Metastatic Cancers Cured with
Chemotherapy and Radiation
 Account for a small percentage of cancers
 Testicular cancer, choriocarcinoma,
Hodgkin’s and non-Hodgkin’s lymphoma,
leukemia, breast cancer, and ovarian cancer
Cancer Therapy
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Lung Cancer
 The most common form of cancer
 The chances of survival are slim if the
cancer is not 100% removed.
 60% of patients die within the first year after
diagnosis.
 15% of patients only survive up to 5 years.
Cancer Therapy
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Breast Cancer
 Slow cancer
 5-10 year survival rate if surgery occurs
 Death rate has declined since 1975
 27% likelihood that a person will survive five
years if the cancer is metastatic
 Early detection by screening
Cancer Therapy
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Breast Cancer (Continued)
 DCIS (ductal carcinoma in situ)
○ 62,000 cases discovered each year
○ In 50% of diagnosed patients, the lesions will not
progress and there is no reason for treatment.
○ American Cancer Society (in 2009) recommended
that all patients with DCIS undergo some sort of
therapy.
○ These patients most likely undergo surgery.
○ It is estimated that, annually, 30,000 patients are
unnecessarily treated for DCIS.
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Prostate Cancer
Pancreatic Cancer
Common Cancers Current Death and Survival Statistics
(American Cancer Society 2009)
% of Cancer
Deaths
One-Year
Survival %
Five-Year
Survival %
Lung
28
41
15
Colon/Rectum
9
83
64
Breast
8
>95
89
Pancreas
6
24
5
Prostate
5
*
*
Leukemia
4
**
51
Lymphoma
4
82
68
Liver
3
***
<10
Other
33
****
****
Cancer Origin
* Survival statistics for prostate cancer are very misleading since they include many treated cancers that would not have
harmed (or killed) the patient.
** Leukemia is a heterogenous group of diseases. The five-year survival figure is an average of all types.
*** Liver cancer is a rapidly fatal disease in which treatment is ineffective.
**** Other cancers are so heterogenous that the reader should consult the American Cancer Society (2009) for specific data.
Smart Drugs
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Smart Drugs
 Drugs that focus on a particular vulnerability of a
type of cancer
90% of these so-called “smart” drugs can
cost more than $20,000 for a 12 week
treatment.
 They generally only offer a survival benefit
of 2 months or less.
 60-80% of oncologists’ revenue comes
from the use of anti-cancer drugs in their
practices.
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Smart Drugs
Bevacizumab (Avastin) is the 9th largest
selling drug in the U.S.
 It is an intravenous man-made antibody
that blocks the growth of VEGF (vascular
endothelial growth factor).
 Tumors and other normal tissue release
VEGF to increase blood vessel growth.
This helps nourish the tissue.
 This drug and others like it rarely make a
patient live longer, or have a better quality
of life.
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Smart Drugs
Bevacizumab (Avastin) - Utility
Cancer
Evidence for Prolongation of Life; time*
Bowel/Rectum
Yes, four months (median survival) with other
drugs
Lung
No+
Breast
No
Kidney
No
Glioblastoma (Brain)
No
*Compared to randomized control (if available).
+ ”No” means a lack of a statistically significant prolongation.
Why Has the War on Cancer Failed?
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We don’t understand the causes of the
majority of cancers.
Most of the treatments (chemotherapy and
radiation) are nonspecific cell killers.
The clinical trials have not fostered innovation,
and they need reform.
The screening for useful drugs against cancer
cells hasn’t worked.
Animal models of cancer tend to be
inadequate.
Cancer research has consistently yielded
unproductive “facts”.
Where Should We Go from Here?
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We do not understand exactly what causes
most cancers.
For example, we know that lung cancer can be
caused by tobacco use. However, we don’t
know exactly how it causes cancer, or how to
effectively treat it.
Are the causes genetic, epigenetic, or are
cancers caused by something else altogether?
Without finding the absolute mechanisms and
root causes of cancers, we cannot expect to
make meaningful progress in this field.
What Should We Do Now?
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Despite the aforementioned lack of
knowledge regarding the cure for
cancer, we can still decrease the rate of
cancer deaths by exploring preventative
measures and early cancer screening.
What Should We Do Now?
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Prevention
 Smoking cessation reduces the risk of lung and other
types of cancer.
 Minimizing hormone therapy reduces one’s risk of
contracting breast cancer.
 Vaccines which are practically 100% effective can be used
to prevent:
○ Hepatitis B (which can cause liver cancer)
○ Human Papilloma Virus (which can cause cervical, anal,
and penis cancers)
 Helicobacter, which is a cause of some stomach cancers,
can be practically eliminated with antibiotics.
 Avoid contracting the AIDS virus. This can lead to the
development of sarcoma.
What Should We Do Now?
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Prevention (continued)
 Chemoprophylaxis (preventative medicine)
○ Finasteride and tamoxifen can be used to
decrease prostate and breast cancer, respectively,
in high risk patients.
 Decreased alcohol consumption can
significantly reduce the occurrences of liver and
esophageal cancers.
 Obesity also can be linked to an increased risk
of contracting many different cancers. If we
curtail obesity, we decrease the risk of having
cancer.
What Should We Do Now?
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Screen for:
 Cervical cancer
 Colorectal cancer
 We should screen for breast cancer, even though it
generally leads to overdiagnosis. The benefit of
overdiagnosis generally outweighs the harm.
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We need a better understanding of different
cancers and their causes.
We need to utilize better animal models in our
research.
Once the appropriate causes and targets are
identified, we need to develop better drugs to
treat cancer patients.
What Should We Do Now?
We definitely need a better
understanding of cancer and its causes.
 If we had this understanding and
followed the prevention and screening
recommendations, we could greatly
reduce the occurrence of cancers.
 Treatment for other ailments and
diseases has progressed greatly along
these paths. Why can’t we do this for
cancer?

Works Cited
Spector, Reynold. "The War on Cancer: A Progress Report for Skeptics." 2012.
Comp. Eileen Daniel. Taking Sides: Clashing Views in Health and
Society. 10th ed. Columbus, OH: McGraw-Hill Higher Education, 2012.
70-79. Print.