Download What is cancer?

Introduction to Cancer
basics?
Candy Cooley, Manager National Genetics Education and
Development Centre
cancernursing.org online lecture March 2009
Statistics
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>9.7 million cases are detected
each year
6.7 million people will die from
cancer
Every day, around 1700
Americans die of the disease
20.4 million people living with
cancer in the world today
1 in 3 people will be diagnosed
with cancer in the UK and 1 in 4
will die from their disease
The Global Burden of Cancer 2000
Women
Men
4.7 million cases
2.7 million deaths
5.3 million cases
3.5 million deaths
Lung
902
337
293
810
Breast
499
Colon/Rectum
255
234
558
Stomach
318
405
398
384
Liver
Prostate
105
0
370
446
241
166
165
543
204
Cervix uteri
471
233
Oesophagus
279
227
260
Bladder
99
Non-Hodgkin
167
Lymphoma
93
144
109
170
81
116
112
Leukaemia
Oral cavity
Pancreas
119
Kidney
57
133
111
76
33
121
68
113
86
97
47
101
101
71
34
Mortality
192
Ovary
114
1000
0
Incidence
800
600
400
200
0
(Thousands)
From: D.M. Parkin The Lancet Oncology 2: 533-543 (2001)
200
400
600
800 100
WHO Statistics

2020 15 million people will die from cancer
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Causes
 Ageing
population
 Obesity
 Smoking
The burden of cancer

6% of NHS hospital expenditure

$/€/£ etc millions spent on research

Substantial financial burdens upon families
and carers

Physical and emotional burden
Personal views of cancer
“in the popular
imagination cancer
equals death”
“Cancer forces us to
confront our lack of
control over our own
or others death”
Kleinman (1988)
(Susan Sontag,1977)
What is Cancer?

Division – uncontrolled cell division

Growth – formation of a lump (tumour) or large
numbers of abnormal white cells in the blood

Mutation – changes to how the cell is viewed by
the immune system

Spread – ability to move within the body and
survive in another part
Division – uncontrolled cell division

Oncogenes

Tumour suppressor genes – p53

Suicide genes – apoptosis

DNA repair genes
Growth

Tumour
 Pressure
on nerves
 Blocking organs
 Stopping normal function
 Altering nerve signals
 Fungating
Mutation and Spread
 Invasion
 Angiogenesis
Types of Cancer
Carcinomas
 Sarcomas
 Lymphomas
 Leukaemias
 Adenomas
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Often prefixed by the specific cell
What are the differences in the
features of normal and cancer cells?
Malignant versus benign
tumours
Normal and abnormal cell
growth
Normal cell growth
Cancerous growth
Metastatic cancer
What causes cancer?
Carcinogenesis.
Some factors to consider…
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Heredity
Immunity
Chemical
Physical
Viral
Bacterial
Lifestyle
Heredity
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5-10% of Cancers
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?15% of all
cancers

Molecular biology
and Human
Genome Project
Heredity
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Genes isolated for
several classic familial
cancer syndromes:

RB1 (retinoblastoma)
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APC (familial polyposis)

Human Non Polyposis
Colon Cancer (HNPCC)

BRCA 1&2 (breast
cancer)

p53 (many cancers)
Immunity

HIV / AIDS

Immunosuppression
Virus’s
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Hepatitis B

Human T-cell
Leukaemia virus
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Epstein Barr Virus
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Human Papilloma
Virus (HPV)
Bacterial

H. pylori
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Other Parasites:
 Schistosoma
spp
 Clonorchis sinensis
Estimated Burden of Cancer from Infection Worldwide in 2000
No. of cases
Agent
% World
cancer
Liver
509,000
HBV, HCV, flukes
5.1
Cervix
471,000
HPV
4.7
Stomach
442,000
H. pylori
4.4
Kaposi’s (HIV related)
134,000
HHV-8
1.3
Non Hodgkin lymphoma
72,000
H. pylori, EBV, HIV
0.7
Ano-genital
65,000
HPV
0.6
Nasopharyngeal
63,000
EBV
0.6
Hodgkin disease
33,000
EBV, HIV
0.3
Bladder
10,000
Schistosoma
0.1
HTLV1
0.03
Leukaemia
Total
3,000
1,801,000
17.9
Chemical
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Alcohol
Asbestos
Wood dust
Rubber, plastics, dyes
Tar / bitumen
Aflatoxin
Alkylating agents
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Tobacco
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Smoking
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Single biggest cause
of cancer
25-40% smokers die
in middle age
9 in 10 lung cancers
Know to cause cancer
in 1950
Smoking and alcohol
Industrial pollution
Physical causes
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Ultraviolet radiation

Sunlight
 Certain industrial sources
Radiation
Radon
Cancer
treatment
Obesity
Lifestyle:
- Highly caloric diet, rich in
fat, refined carbohydrates
and animal protein
- Low physical activity
Consequences:
- Cancer
- Diabetes
- Cardiovascular
disease
- Hypertension
Lifestyle
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Age
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Occupation
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Ethnicity
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Deprivation
Survival variations
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CONCORD Study (1.9 million survivors)
demonstrated a clear relationship to
income not only between countries but
also between the ethnic groups in those
countries

(Coleman et al Lancet Oncology 2008)
Diagnosis and staging
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Clinical History

Normal diagnostic procedures
 Scans,
xrays
 Blood tests
 Biopsy
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Pathological staging
Staging
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Size

Invasion
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Lymph nodes
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Metastasises
TNM Staging
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T (a,is,(0),1-4): size or direct extent of the primary tumor
N (0-3): degree of spread to regional lymph nodes
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N0: tumor cells absent from regional lymph nodes
N1: tumor cells spread to closest or small number of regional
lymph nodes
N2: tumor cells spread to an extent between N1 and N3.
N3: tumor cells spread to most distant or numerous regional
lymph nodes
M (0/1): presence of metastasis
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M0: no distant metastasis
M1: metastasis to distant organs (beyond regional lymph nodes)
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Other parameters
G (1-4): the grade of the cancer cells (i.e. they are "low
grade" if they appear similar to normal cells, and "high
grade" if they appear poorly differentiated)
R (0/1/2): the completeness of the operation (surgeryboundaries free of cancer cells or not)
L (0/1): invasion into lymphatics
V (0/1): invasion into vein
C (1-4): a modifier of the certainty (quality) of the last
mentioned parameter
Examples
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Small, low grade cancer, no metastasis, no spread to
regional lymph nodes, cancer completely removed,
resection material seen by pathologist - pT1 pN0 M0 R0
G1; this would be considered Stage I.
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Large, high grade cancer, with spread to regional lymph
nodes and other organs, not completely removed, seen
by pathologist - pT4 pN2 M1 R1 G3; this would be
considered Stage IV.
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Most Stage I tumors are curable; most Stage IV tumors
are not.
Staging for Chronic Lymphocytic
Leukemia (CLL)
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There are two different systems for staging
chronic lymphocytic leukemia. The Rai
classification is used more often in the United
States, whereas the Binet system is used more
widely in Europe
Stages of Leukemia: Acute
Lymphocytic Leukemia (ALL)
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For adults, ALL is classified as untreated, in remission,
or recurrent. For childhood ALL, risk groups are used
instead of stages to describe cases of the disease. Risk
groups for childhood ALL include:
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Standard (low) risk
High risk
Recurrent.
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Other staging
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Lymphoma: uses Ann Arbor staging
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Hodgkin's Disease: follows a scale from I-IV and
can be indicated further by an A or B, depending
on whether a patient is non-symptomatic or has
symptoms such as fevers. It is known as the
"Cotswold System" or "Modified Ann Arbor
Staging System".
Duke Staging System
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Modified Duke A The tumor penetrates into the mucosa of the
bowel wall but no further.
Modified Duke B B1: tumor penetrates into, but not through the
muscularis propria (the muscular layer) of the bowel wall. B2: tumor
penetrates into and through the muscularis propria of the bowel wall.
Modified Duke C C1: tumor penetrates into, but not through the
muscularis propria of the bowel wall; there is pathologic evidence of
colon cancer in the lymph nodes. C2: tumor penetrates into and
through the muscularis propria of the bowel wall; there is pathologic
evidence of colon cancer in the lymph nodes.
Modified Duke D The tumor, which has spread beyond the
confines of the lymph nodes (to organs such as the liver, lung or
bone).
Summary
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Cancer is a disease of
Division, growth and
spread
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It has a number of causes
many of them
preventable
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The survival of the patient
is determined by the
stage of the disease, the
earlier the detection or
the smaller the tumour
the better the survival
10 Rules to Avoid Cancer
1.
2.
3.
4.
Don’t smoke
Don’t smoke.
Don’t smoke.
Avoid exposure to other known carcinogens,
including aflatoxin, asbestos and UV light.
5. Enjoy a healthy diet, moderate in calories,
salt and fat, and low in alcohol.
6. Eat fresh fruit and vegetables several times a day.
7. Be physically active and avoid obesity.
8. Have vaccination against, or early detection/treatment
of, cancer causing chronic infections.
9. Have the right genes.
10. Have good luck !