Introduction to Cancer basics?

Candy Cooley, Manager National Genetics Education and Development Centre

cancernursing.org online lecture March 2009

Statistics >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

Lung

Breast

Colon/Rectum

Stomach

Liver

Prostate

Cervix uteri

Oesophagus

Bladder

Non-Hodgkin

Lymphoma

Leukaemia

Oral cavity

Pancreas

Kidney

Ovary

1000 800 600 400 200 0 200 400 600 8001000

Men Women

From: D.M. Parkin The Lancet Oncology 2: 533-543 (2001)

(Thousands)

Incidence

Mortality

337293

1050370

241318

446234

165166

471233

133111

7633

12168

11386

4797

101101

3471

192114

810902

558405

255499

398384

204543

279

260227

99

93167

144109

81170

116112

57119

5.3 million cases3.5 million deaths

4.7 million cases2.7 million deaths

The Global Burden of Cancer 2000

WHO Statistics

2020 15 million people will die from cancer

CausesAgeing populationObesitySmoking

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”

(Susan Sontag,1977)

“Cancer forces us to confront our lack of control over our own or others death”

Kleinman (1988)

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

TumourPressure on nervesBlocking organsStopping normal functionAltering nerve signalsFungating

Mutation and Spread

Invasion

Angiogenesis

Types of Cancer

Carcinomas Sarcomas Lymphomas Leukaemias Adenomas

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… Heredity Immunity Chemical Physical Viral Bacterial Lifestyle

Heredity 5-10% of Cancers

?15% of all

cancers

Molecular biology

and Human

Genome Project

Heredity Genes isolated for

several classic familial

cancer syndromes:

RB1 (retinoblastoma)

APC (familial polyposis)

Human Non Polyposis

Colon Cancer (HNPCC)

BRCA 1&2 (breast

cancer)

p53 (many cancers)

Immunity

HIV / AIDS

Immunosuppression

Virus’s

Hepatitis B

Human T-cell

Leukaemia virus

Epstein Barr Virus

Human Papilloma

Virus (HPV)

Bacterial H. pylori

Other Parasites: Schistosoma spp Clonorchis sinensis

Estimated Burden of Cancer from Infection Worldwide in 2000

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

Leukaemia 3,000 HTLV1 0.03

Total 1,801,000 17.9

No. of cases Agent % Worldcancer

Chemical

Alcohol Asbestos Wood dust Rubber, plastics, dyes Tar / bitumen Aflatoxin Alkylating agents

Tobacco

Smoking

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

Ultraviolet radiation Sunlight Certain industrial sources

RadiationRadonCancer treatment

Obesity Lifestyle:- Highly caloric diet, rich in fat, refined carbohydrates and animal protein- Low physical activity

Consequences:- Cancer - Diabetes- Cardiovascular disease- Hypertension

Lifestyle

Age

Occupation

Ethnicity

Deprivation

Survival variations

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

Clinical History

Normal diagnostic procedures Scans, xrays Blood tests Biopsy

Pathological staging

Staging

Size

Invasion

Lymph nodes

Metastasises

TNM Staging

T (a,is,(0),1-4): size or direct extent of the primary tumor N (0-3): degree of spread to regional lymph nodes

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

M0: no distant metastasis M1: metastasis to distant organs (beyond regional lymph nodes)

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 (surgery-boundaries 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 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.

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.

Most Stage I tumors are curable; most Stage IV tumors are not.

Staging for Chronic Lymphocytic Leukemia (CLL)

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)

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:

Standard (low) risk High risk Recurrent.  

Other staging

Lymphoma: uses Ann Arbor staging

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

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

Cancer is a disease of Division, growth and spread

It has a number of causes many of them preventable

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

2. Don’t smoke.3. Don’t smoke.4. Avoid exposure to other known carcinogens, including aflatoxin, asbestos and UV light.

6. Eat fresh fruit and vegetables several times a day.7. Be physically active and avoid obesity.

8. Have vaccination against, or early detection/treatmentof, cancer causing chronic infections.

9. Have the right genes.

10. Have good luck !

5. Enjoy a healthy diet, moderate in calories, salt and fat, and low in alcohol.

1. Don’t smoke