PPT for undergraduate 6th semester students of Community Medicine

1. Dr. Kuntala Ray
Associate Professor
Cancer
1

2. OUTLINE OF PRESENTATION
 Definition
 Pathogenesis and Symptoms
 Situational Analysis
 Approaches In Cancer Control
 Warning Signals For Cancer Control
 Screening
 Diagnosis and prevention of some imp.
cancer
2

3. Definition
 A group of disease characterized by an-
1. Abnormal growth of the cell
2. Ability to invade adjacent tissue and even
distant organ
3. The eventual death of the affected patient if
the tumor has progressed beyond that stage
when it can be successfully removed.
3

4. Problem statement
 WORLD
10 million new cases each year
4.7 million in developed countries
5.5 million in less developed countries
12% deaths worldwide
20 years time – no. of cancer deaths will rise
from 6 million to 10 million per year
4

5. Incidence of cancer in India
5

6. Cancer and its Spread
6

7. Patho-physiology
Healthy
cell
Dysplasi
a
Ca in
situ
Localise
d
Invasive
Ca
Regional
Lymph
node
involveme
nt
Distant
metastasi
s
7

8. Categories
1. According to cell of origin
 Carcinomas
 Sarcomas
 Lymphomas/leukaemias
2. According to localization
 Primary tumour
 Secondary tumour
8

9. Common Cancers (India)
MALE FEMALE
1. Lung cancer
2. Lip & oral cavity
3. Stomach &
colorectal
4. Pharynx
1. Breast
2. Cervix
3. Colorectal
4. Ovary
5. Lip & oral cavity
Note : Breast Cancer
is commonest
among urban
females.
9

10. Cancer trends
 Is changed from 6th to 2nd position in leading
cause of death because-
1. Longer life expectancy
2. More accurate diagnosis
3. Rise in cigarette smoking
10

11. Cancer pattern
 Cancer in stomach is very common in Japan
and low incidence in USA.
 Cervical cancer is more common in Columbia
but low in Japan
 In SEAR of WHO majority are cancer of oral
cavity, uterine cervix
 Two organ sites 1. uterine cervix 2. Oro-
pharynx represent 50% of all cancer cases;
predominantly have a environmental and
socio-cultural relationship.
11

12. Causes of cancer
1. Environmental
factors 2. Genetic factors
 Tobacco
 Alcohol
 Dietary factors
 Occupational
exposure
 Virus
 Parasites
 Customs / habits /
lifestyle
 Retinoblastoma
occurs in children of
the same parents
 Mongols more likely
to develop leukaemia
than normal children
12

13. Recognised cancer risk factors
0 10 20 30 40 50 60 70 80
diet
tobacco
infection
sexual/reproductive
occupation
geophysical
alcohol
pollution
food additives
industrial products
medical procedures
% of cancer risk
diet
tobacco
infection
sexual/reproductive
occupation
die
tob
inf
se
oc
ge
alc
po
foo
ind
me
13

14. Natural History of Cancer
14

15. Primary objectives of cancer treatment
 Cure
 Prolongation of life
 Improvement of quality of life
15

16. Cancer control
 Primary prevention
1. Control of tobacco and alcohol consumption
2. Personal hygiene
3. Radiation exposure
4. Occupational exposure
5. Immunization
6. Foods, drugs and cosmetics
7. Air pollution
8. Treatment of precancerous lesion
9. Legislation
10. Cancer education16

17. Tobacco
 The single most important modifiable risk factor
 Of all cancers in India, 34% are due to tobacco
(48% of cancers in men and 20% of cancers in
women).
 Tobacco smoke contains approximately 4000
chemicals of which at least 438 can cause cancer.
 Tobacco smoking causes cancer of the lung, larynx
and oesophagus, cancers of the pancreas, bladder,
pelvis of the kidneys, ureter and SCC of the uterine
cervix.
 “Passive Smoking” results in increased risk of
cancers among non- smokers exposed to tobacco
smoke.17

18. Alcohol
 alcohol consumption associated with cancers of
the mouth, pharynx (excluding nasopharynx),
larynx, oesophagus and liver.
 A nearly linear risk relationship seen between
cancer and alcohol with the risk increasing with
increasing amount of alcohol consumed.
 Control of alcohol requires actions similar to those
for tobacco control. The actions should be targeted
towards individual and community and include
taxation, general public education, encouraging
highly vulnerable groups like young people.
18

19. Sexual and reproductive factors
 Sexual and reproductive factors are associated with
cancer of the uterine cervix and breast.
 Sexual behaviour factors, like young age at first
sexual activity, multiple sexual partners and poor
sexual hygiene, are associated with cancer of the
uterine cervix.
 Human Papilloma Virus (HPV) has now been
identified as the etiological agent responsible for
cervical cancer. HPV prevalence increases with high
risk sexual behaviour and poor sexual hygiene.
 Late age at marriage, nulliparity, and late menopause
have been linked to breast cancer, but the underlying
mechanism is probably uninterrupted exposure to19

20. Diet
 It is generally agreed that diets rich in animal
fats, especially red meats, increase the risk for
cancer.
 It is also widely accepted that diets high in
fresh vegetables and fruits, and fibre reduce
risk for cancer
 Certain basic measures may help in
reducing risk of cancer:
Avoid being underweight or overweight
Engage in regular physical activity
Consumption of alcohol is not recommended
Limit consumption of salted foods20

21. Measures taken
 Legislative action
 Education of youths & adults
 Multi-sectoral comprehensive approach
Cigarette act (1975)-
Cigarette smoking is injurious to health
Prevention of food adulteration rules (1990)
Chewing of tobacco is injurious to health
Legislative action
21

22. Occupation
 Occupational cancers constitute 5-10% of all
cancers.
 Increased risk of lung cancer has been seen in
workers engaged in manufacture of rubber tyres in
developing countries, textile workers, ship and
dockyard workers and wood workers.
 Higher risk of bladder cancer was seen in workers
of chemical and pharmaceutical plants.
 Limiting exposure to potentially carcinogenic
substances through protective gear, frequent
rotation of workers, mechanized handling of such
chemicals and similar mechanisms may help22

23. Secondary prevention
 Early detection of cases
 Cancer registration
 Treatment
23

24. Early detection
 Early detection of cancer is the detection of
disease at a stage in its natural history where the
chance of cure is high.
 Early detection is only part of a wider strategy
that includes diagnosis, treatment and follow-up.
 Many cancers that are potentially curable at early
stages are detected only in advanced stages.
 Diagnosis of such cancers at a stage where
treatment is effective could have a major impact24

25. Warning signals for Cancer
 C hange in bowel or bladder habits
 A wound that does not heal
 U nusual Bleeding or discharge
 T hickening or Lump in the breast or elsewhere
 I ndigestion or difficulty in swallowing
 O bvious change in a wart or mole
 N aging cough or hoarseness of voice
25

26. CANCER REGISTRATION
Principal objective:
1. To generate authentic data on magnitude of
problem
2. To undertake control measures
3.To promote human resource development in
cancer epidemiology
26

27. Types
1. Hospital based – all pt treated by a particular
institution whether inpatient or out patient
following WHO recommended uniform minimum
set of information. In long term follow up can be
used for evaluation of diagnostic and treatment
program.
2. Population based- it aims to cover the
complete cancer situation in a given geographic
area. Optimum size of base population is in the
range of 2-7 million. It can provide incidence
rate of cancer, surveillance of time trends,
planning and evaluation of operational activities.
27

28. DELHI
BHOPAL
MUMBAI
AHMEDABAD
THIRUVANANTHAPURAM
CHENNAI
BANGALORE
ICMR HEAD QUARTERS
NCRP COORDINATING UNIT
POPULATION BASED REGISTRY
POPULATION BASED RURAL REGISTRY
HOSPITAL BASED REGISTRY
DIBRUGARH
SIKKIM
GUWAHATI
SILCHAR IMPHAL
MIZORAM
NATIONAL CANCER REGISTRY PROGRAMME
(Indian Council of Medical Research)
BARSHI
KOLKATTA
14 Population Based
6 Hospital Based
■
CHANDIGARH
28

29. Early detection & screening
 Best way to control- to detect early
 SCREENING
Screening is the presumptive identification of
unrecognized disease or defects by means of tests,
examination, or other procedures that can be applied
rapidly
Source: WHO. NCCP, 1995
PREREQUISITES FOR SCREENING
•Highly acceptable
•Inexpensive
•Highly applicable to large population
•Simple & noninvasive
• high sensitivity & specificity
29

30. Cancer screening
 Search for unrecognized malignancy by
means of rapidly applied test.
 It is possible because –
a. Malignant disease preceded by a pre-
malignant lesion removal of which prevents
subsequent development of cancer.
b. Most cancer begins at localized lesion & at
this stage high rate of cure can be
obtainable.
c. 75 % of all cancer occurs in body sites that
are accessible.30

31. Majority of cancer in our country
are from easily accessible sites
- ca cervix
- ca breast
- ca lung
- oral cavity cancers
- ca colon
31

32.  Population screening successful in reducing
morbidity & mortality in countries with high level
resources
 Our problem- screening of an asymptomatic
population in a large country with limited
resources
 Hence only screening of high risk cases
32

33. Cervical Cancer Biology
Normal
Cervix
HPV
Infection
Persistent
HPV
Infection
Cervical
Dysplasia
(pre-cancer)
Cervical CancerVACCINATION SCREENING
33

34. Screening for cervical cancer
13% cancers if cervix can be potentially screened & treated
successfully
 Pap Smear Screening
 Visual Inspection of Cervix
 Visual Inspection of Cervix after magnification
 Visual Inspection of Cervix after acetic acid, lugol’s iodine
 HPV detection
Regardless of method of Screening, it is important to
establish and run an efficient network for this purpose.
34

35. Sensitivity of PAP 51%
FALSE NEG – 5-50%
20% LAB ERRORS
35

36. Visual Inspection Method
 simple speculum examination
VISUAL INSPECTION WITH ACETIC ACID (VIA )
 Acetic acid – malignant cells stain white
- Dissolves mucus
– Induces intracellular dehydration
– Causes coagulation of protein
Sensitivity and specificity of VIA - 70-92%
VISUAL INSPECTION LUGOLS IODINE
Iodine being glycophilic stains only the normal
squamous epithelium-mahogany brown or black
Sensitivity 91.7% specificity 85.9%
36

37. Visual inspection method
Unaided visual inspection of Cx – “Clinical Down
staging”
 simple speculum examination
 done by nurses & nonmedical health
workers
 expected to minimise the cancer death
but not the incidence
37

38. VISUAL INSPECTION WITH ACETIC ACID (VIA
)
Become opaque –aceto white
area –test positive
Sensitivity and specificity of VIA - 70-92%
Positive Predictive Value - 15-20%
38

39. VISUAL INSPECTION OF CERVIX WITH ACETIC ACID (VIA)
Visualization of the acetic acid-
washed cervix using a good
light source to facilitate cervical
cancer screening & possibly to
guide biopsy & treatment of
pre-invasive lesions
39

40. Approaches to Cervical Cancer
Prevention in Low-resource Settings
Source-Program for Appropriate Technology in Health [PATH] 1997.
Effective Safe Practical Affordable Available
Visual
Inspection:
AA
Yes Yes Yes Yes Yes
Visual
Screening:
Unaided
No Yes Yes Yes Yes
Automated
Pap Screening
Yes? Yes ? No No
HPV
Screening
Yes Yes ? ? Yes
Cervicography Yes? Yes ? ? Yes
HPV Vaccine ? ? Yes ? No
40

41. Limitations of Pap Smears for
National Screening Programs
 Pap smear-based programs require complex logistics,
advanced training, and well managed program
implementation for adequate testing to occur.
 These elements are not available outside large cities
in many low-resource settings.
 Even in large cities, quality pap smears are possible but
ongoing supervision, refresher training and continued
supplies are necessary.
 Cytology is not viable as a nationally accessible
screening method in Low Resource Settings.
41

42. Screening for breast cancers
 Data from HBCR-
 15 % - localized state
75 % - lymph nodes at presentation
10 % have mets at presentation
42

43. Screening for breast cancers
 Breast cancer screening programs involving
expensive imaging techniques
 Cannot be adopted in developing countries like
India as a routine public health measure
Breast cancer would be best tackled through an
early detection programme using Clinical Breast
Examination (CBE) performed by trained
paramedical personnel such as female health
workers
Screening by CBE can be potentially as effective as
screening by Mammography
43

44. ( Once a month 10 days after menstrual period )
44

45. 45

46. Patient with a lump in breast
(detected by BSE )
Clinical examination by health care professional
Refer to higher centre for investigation
Reassurance- all lumps need not be cancer
Benign lump-
reassurance
Malignant lump-
prompt referral for app t/t
46

47. Screening for oral cavity cancers
 Disease occurs in poor - majority illiterate
 Not bothered for oral cavity examination
Oral examination followed by indirect/ direct laryngoscopy
if needed is the standard procedure followed
Smokers are also routinely investigated for pulmonary lesions
by simple x-ray of the chest.
47

48. 48

49. Treatment
 Surgery
 Radiotherapy
 Chemotherapy
 Hormonal therapy
49

50. What are the operations
 Radical surgery
- tumour + draining LN+ areas of potential
spread
 Palliative surgery
- colostomy , debulking, toilet mastectomy etc.
50

51. Prophylactic Surgery
Clinical condition Associated
malignancy
Recommendations
MEN 2A, 2B Medullary
thyroid cancer
Total thyroidectomy
Barrett’s
esophagus
Adeno Ca
esophagus
Esophagectomy
Hereditary diffuse
gastric cancer
Gastric cancer Gastrectomy
BRCA1 mutation
BRCA2 mutation
Breast cancer B/L total
mastectomy
B/L oophorectomy
Ovarian cancer
51

52. Prophylactic Surgery
Clinical condition Associated
malignancy
Recommendations
Ulcerative colitis Colon cancer Colectomy (at 20yrs)
FAP Colon cancer Colectomy (teenage
yrs)
HNPCC Colon cancer Surveillance
colonoscopy &
polypectomy
Cryptorchidism Testicular
cancer
Orchiopexy/
Orchiectomy
52

53. Chemotherapy
53

54. Augmentation of treatment facilities
 Cancer chemotherapy
 Essential drug list for cancer chemotherapy & services for
common cancers made available
 Advanced facilities for high intensity chemotherapy for
leukaemia & other cancers where chemotherapy mainstay of
treatment provided at regional cancer centres
54

55. Radiation
 TELETHERAPY
 using radioactive source- Cobalt machines
 using electric energy - Linear accelerator
55

56. Brachytherapy
56

57. Regular check up
 After treatment completion
 Important to detect early if any spread occurs
 Life long check up important
 No need to go to distant far off best places
57

58. The HPV- cervical cancer link
 Human papillomavirus
(HPV) is a very common
infection (more than 50% of
adults get it, in most it is a
transitory infection)
 99.7% of cervical cancer
cases are associated with
HPV
 Progression from HPV
infection to cancer usually
takes 20-30 years
 Currently, there is no
treatment for HPV infection
53%
15%
9%
6%
3%
14%
HPV 16
HPV 18
HPV 45
HPV 31
HPV 33
HPV others
Global distribution of HPV types in
cervical cancer
58

59. HPV Vaccines
 The US Food and Drug Administration (FDA) approved Gardasil
[Quadrivalent HPV (Types 6, 11, 16, 18) Recombinant Vaccine], the
first HPV vaccine for children and young adults, female, ages 9-26
years.
 Gardasil is manufactured by Merck & Co., Inc: vaccine, protects
against HPV types 16 and 18, which are responsible for about 70%
of all cervical cancers,
 GlaxoSmithKline has also developed its bivalent HPV vaccine,
Cervarix for HPV types 16 and 18. It will be submitted for
regulatory approval in Europe and countries outside the USA.
 Clinical research has shown that both vaccines are safe and
effective in preventing infection with the HPV 16 and 18 types.
 The two HPV vaccines under consideration are considered
“prophylactic” rather than “therapeutic” vaccines and optimally
should be administered prior to natural exposure to the vaccine
HPV types.59

60. HPV - Vaccination
 HPV Vaccines may be:
- Prophylactic (induction of neutralizing antibodies)
- Therapeutic (induction of cellular immunity against
cells expressing viral proteins)
- Combination of both
 Potentially safe & effective means of preventing or
controlling disease
 HPV vaccine, at age 11→ eliminate 70% of cervical
cancer
 30% of cervical cancers not prevented by HPV vaccine
 Vaccinated females could subsequently be infected
with non-vaccine HPV types
 Sexually active females could have been infected prior
to vaccination60

61. HPV Vaccination Schedule
 Routine schedule is 0, 2, 6 months
 Minimum intervals
 4 weeks between doses 1 and 2
 12 weeks between doses 2 and 3
 Do not restart the series if the schedule is interrupted
 Administer at same visit as other age-appropriate
vaccines
 Adverse Reactions - Local reactions (pain, swelling),
Fever
 Contraindications
 Severe allergic reaction to a vaccine component or
following a prior dose
 Precaution
 Moderate or severe acute illnesses (defer until
symptoms improve)
61

62. Epidemiology of selected
cancer
62

63. Oral cancer
 Oral cancer is one of the ten most common cancers in
the world; high frequency in Central and South East
Asian countries
 Oral cancer is a major problem in India; estimated in
2016 it caused 4.5 deaths per 100,000 population
 Approximately 90 per cent of oral cancers in South
East Asia are linked to tobacco chewing and tobacco
smoking.
 oral cancer was almost always preceded by some type
of precancerous lesion; leukoplakia, erythroplakia can
be detected for upto 15 years prior to their change to
an invasive carcinoma
 Another type of cancer common in the eastern coastal
regions of Andhra Pradesh state is the epidermoid
63

64. Prevention
 Primary: If the tobacco habits are eliminated from
the community, a great reduction in the incidence
of oral cancer can be achieved. This requires
intensive public education and motivation for
changing lifestyles supported by legislative
measures like banning or restricting the sale of
tobacco
 Secondary : The precancerous lesions can be
detected for up to 15 years, prior to their change
to an invasive carcinoma. Leukoplakia can be
cured by cessation of tobacco use.
 So early detection by the primary health worker
during home visits is the main treatment modality
in secondary prevention. Surgery and64

65. Breast cancer
 The most frequent cancer among women with on
estimated 2.1 million new cases diagnosed in 2018
 In India, breast cancer was estimated to cause 6.1
deaths per 100,000 population in the year 2016
 Established risk factors of breast cancer include- age
(35-50yrs and >65 yrs), family history, parity, age at
menarche and menopause, hormonal factors, diet etc.
 Primary prevention: The average age at menarche can
be increased through a reduction in childhood obesity,
and an increase in strenuous physical activity; and the
frequency of ovulation (after menarche) decreased by
an increase in strenuous physical activity, reducing fat
intake in the diet.
 Secondary prevention: Breast screening as early
diagnosis and removal of tumour65

66. Lung cancer
 Worldwide, lung cancer remains the leading cause of
cancer incidence and mortality, with 2.1 million new
lung cancer cases and 1.8 million deaths predicted in
2018
 In India, the age standardized incidence rate for the
year 2016 was total 8.4 per 100,000 population
 About a third of all lung cancer deaths occur below
the age of 65.
 Risk factors- smoking(cigarette smokers is 8.6 times
the risk for non-smokers; The most noxious
components of tobacco smoke are tar, carbon
monoxide and nicotine), air pollution, radioactivity, and
occupational exposure to asbestos, arsenic and its
66

67. Prevention
 Primary: WHO expert committee recommend
a . Public information and education(through mass media)
b . Legislative and restrictive measures
 (control of sales promotion; health warnings on cigarette
packets and advertisements; product description showing
yield of harmful substances; imposition of upper limits for
harmful substances in smoking materials; taxation; sales
restrictions; restriction on smoking in public places;
restriction on smoking in places of work)
 "The Cigarettes And Other Tobacco Products (Prohibition
of Advertisement and Regulation of Trade and Commerce,
Production , Supply and Distribution) Act 2003 was
passed by the Govt of India .
c . Smoking cessation activities
d. National and international coordination
 Secondary: Early detection of cases and their treatment67