 |
Article
Cancer in a Developing Country: Opportunities
and Formidable Challenges
The developed countries are witnessing a progressive decline in
age-adjusted cancer incidence, as well as a leveling in number of
cancer deaths. These declines in incidence and mortality can be
attributed to a number of factors, including public and professional
education, primary prevention, early detection and treatment. These
trends, however, are unfortunately not present in developing countries.
It is estimated that by 2020, 70% of cancer in the world will be
diagnosed in developing countries, causing some nine million annual
cancer deaths.
KCR (1995-1999) (n=3891) |
|
AFIP (1984-1988) (n=5449) |
|
AIMC (1997-2000) (n=1629) |
| Site |
ASR
|
Site |
% |
Site
|
% |
| Lung |
20.0 |
Lymph
node |
10.79 |
Leukemia |
23.6 |
| Oral
Cavity |
16.6 |
Leukemia |
8.01 |
NHL |
15.1 |
| Larynx |
9.4 |
Bronchus |
6.97 |
Bronchus |
7.5 |
| Urinary
Bladder |
9.4 |
Prostate |
6.93 |
Colorectal |
6.7 |
| Pharynx |
7.9 |
Skin |
6.20 |
Liver |
5.8 |
Table 1. Comparison of the rank order of the
five most common tumor sites in males in three registries, one
population based, in Pakistan. KCR: Karachi cancer registry
for Karachi South, AFIP: Armed Forces Institute of Pathology,
Rawalpindi, AIMC: Allama Iqbal Medical College, Lahore. ASR
= Age Standardized Rate (see President’s message). N = number
of cases.
% = percentage of all cancer cases. |
Pakistan is a developing country with a population of 150 million
people. Average life expectancy is 62 years. It is estimated that
160,000 new cancer cases are diagnosed annu.ally. The total expenditure
in the health sector by the government was 0.7% of GNP for the year
2002-03. Health care services are provided to the public through
a vast infrastructure of health care facilities, which include government
hospitals, private hospitals, basic health units and dispensaries.
Less than 5% of the population is fully or partially covered by
health insurance. The major health priorities of the government
are communicable diseases and maternal and child health. Thirty
percent of the population live below the poverty line (defined as
a GNP per capita of less than US$ 480) - earning less than US$140
per annum. Of these, 32% belong to the rural population while 19%
live in urban regions. The overall literacy rate (defined by the
ability to write one’s name!) is 50.5 % (63% males and 38% females).
Rural and urban literacy rates are between 30% and 70%. Malnutrition,
infectious diseases, poverty, hunger and environmental hazards are
some of the major problems faced by the poor. They are locked in
a vicious cycle that keeps them poor, backward and deprived of basic
rights, both socially and politically.
Cancer Epidemiology in Pakistan
According to WHO, 80% of all cancers in developing countries are
due to environmental factors, infectious agents and diet. Smoking
has become a major health hazard in developing countries. In Pakistan,
a conservative estimate is that 50% of males and 9% of females are
habitual smokers. This does not include children, particularly in
the lower socio-economic groups, among whom smoking has increased
tremendously. Tobacco-related cancers are increasing rapidly in
incidence because of the dramatic rise of tobacco smoking in developing
countries. Betel-leaf and tobacco chewing is common in South Asia,
and contributes to the relatively high incidence of head and neck
cancers. The prevalence of Hepatitis B & C ranges from 3.5%-18.6%
and 4%-25.6% respectively, such that one of the consequences of
infection with these viruses, hepatocellular carcinoma, is relatively
common in males. In addition, aflotoxins, derived from a fungus,
are commonly found in stored food grains. They are believed, together
with malnutrition, to contribute to the increasing incidence of
liver cancer. H.pylori infection (a bacterium associated with peptic
ulceration, gastric cancer and gastric lymphoma) is common in developing
countries, with infection rates ranging from 80-100%. Indiscriminate
use of cheap and expired pesticides by farmers in the heavily agricultural
province of the Punjab may account for the relatively high prevalence
of lymphomas and leukemias, which have been shown, in the USA and
elsewhere, to be associated with exposure to herbicides and other
chemicals.
KCR
(1995-1999)
(N=3684) |
|
AFIP
(1984-1988)
(N=3858) |
|
AIMC
(1997-2000)
(N=1783) |
| Site |
ASR
|
Site |
% |
Site
|
% |
| Breast |
56.6 |
Breast |
27.65 |
Breast |
38.5 |
| Oral
Cavity |
15.4 |
Skin |
6.29 |
Ovary |
13.6 |
| Ovary |
9.6 |
Cervix |
4.76 |
Leukemia |
10.3 |
| Cervix |
7.4 |
Leukemia |
4.61 |
NHL |
5.7 |
| Oesophagus |
7.0 |
Ovary |
4.48 |
Gall
Bladder |
4.2 |
Table 2. Comparison of the rank order of the
five most common tumor sites in females in three registries,
one population based, in Pakistan. KCR: Karachi cancer registry
for Karachi South, AFIP: Armed Forces Institute of Pathology,
Rawalpindi, AIMC: Allama Iqbal Medical College, Lahore. ASR
= Age Standardized Rate (see Presidents message). N =
number of cases.
% = percentage of all cancer cases. |
There are no population-based cancer registries in Pakistan except
the Karachi Cancer Registry (KCR). The true magnitude of the cancer
problem is therefore unknown. In women, breast cancer is the most
common cancer throughout Pakistan, and according to KCR, the age-standardized
rate is 56.6 per 100,000 women per year. No identifiable risk factors
are present, however, in 75% of patients with breast cancer. Gall
bladder cancer is the fifth most common cancer in our female population.
Contributing factors include gall stones, diet, infections and a
sedentary lifestyle in this group of patients.
In the developing world, more than 80% of all cancer patients
are incurable by the time they are diagnosed. This is particularly
true for patients from the less affluent strata (>60%) where
multiple factors operate, among which are economic constraints,
illiteracy and poor access to health care facilities. Other contrib.utory
factors are ignorance of patients and health professionals and disease
stigma. The prior use of alternative medicines, hakims (traditional
medicine practitioners) and homeopaths also delays appropriate cancer
care. This is especially common in the rural areas as such approaches
are a cheap alternative to the costly conventional health care systems.
Co-morbid conditions like tuberculosis, hepatitis and malnutrition
are common in the poorer patients with cancer. Large family size,
small living quarters and poor hygiene cause recurrent infections.
Our data on breast cancer treatment and survival outcome reveals
that 75% of patients from the upper strata have early disease and
their outcome is similar to their counterparts in the developed
countries. Patients belonging to the lower strata (80%), on the
other hand, present with advanced disease and exhibit inferior survival.
Similar observations have been made in developed countries in patients
belonging to the lower socio-economic strata.
Cancer Treatment in Pakistan
Facilities for treatment of cancer patients are available in a
few larger cities in both public and private hospitals. There are
18 radiotherapy centers with 65 practicing radiation oncologists;
the quality of these centers is extremely variable depending on
the expertise of the physician and available equipment. There are
only 15 medical oncologists practicing in major cities. State-of-the-art
surgical oncology is practiced in only a few hospitals, and as a
result, the majority of patients undergo sub-optimal surgery.

Street scene in a small town in Pakistan.
|
In Pakistan, profound differences exist with respect to the availability
of medical care to different segments of the population. Good quality
hospital care is available to the affluent class, either from a
small number of excellent public sector hospitals, or from the private
sector. The less affluent classes are provided free services in
the government hospitals but again, the quality of these services
is extremely variable, depending on the available resources and
trained personnel. The financial burden of treatment is borne by
the patients, which makes it difficult for the poor to receive state-of-the-art
treatment. They are supported by monetary donations from individuals
as well as government funds and Zakat, a tax that the more wealthy
Muslims pay specifically to help the poor. These contributions tend
to be insufficient and erratic. Clearly these resources are inadequate
to deal with the ever increasing economic burden of cancer patients.
It is estimated that fewer than 30% of patients receive the minimal
recommended treatment for their disease.
| Year
2000 |
|
|
Males |
|
Females |
| Age
Group. |
Age
specific rate |
Number
of new cases |
Age
specific rate |
Number
of
new cases
|
| 0-14 |
12 |
4017 |
7 |
2277 |
| 15-44 |
41 |
14910 |
76 |
25210 |
| 45-54 |
197 |
10952 |
352 |
17769 |
| 55-64 |
462 |
14306 |
518 |
15662 |
| 65+ |
706 |
17439 |
559 |
14177 |
| All
ages |
76 |
61624 |
99 |
75095 |
| |
| Expected
cancer burden in the Year 2025 |
| 0-14 |
|
12 |
4766 |
|
7 |
2707 |
| 15-44 |
41 |
27100 |
76 |
48076 |
| 45-54 |
197 |
24818 |
352 |
40683 |
| 55-64 |
462 |
42228 |
518 |
44902 |
| 65+ |
706 |
49378 |
559 |
41302 |
| All
ages |
110 |
148290 |
137 |
177731 |
| Data
from Globocan. 1. |
Table 3. Expected increase in cancer cases - all sites but skin
- and annual incidence rates per 100,000 in Pakistan for 2025
compared to 2000. |
What Can Developing Countries Do?
The absence of population-based tumor registries is a major drawback.
Information about cancer is largely extrapolated and no formal policies
for cancer control have been made. Data from the hospital-based
tumor registries are not organized, information is fragmented, and
it is likely that regional variations in cancer incidence and types
occur. It is essential that governments in developing countries
use their meager resources to develop population-based cancer registries,
form policies on prevention of preventable cancers, provide optimal
training of their personnel, and develop regional sites for cancer
treatment with good diagnostic facilities.
Education
Education is essential to improving the results of cancer treatment
as it will result in early detection of cancers and possibly cure
in some patients. It has to be done at three levels. Community education,
physician education and patient education are all essential to creating
cancer awareness and improved treatment options. Education should
also focus on smoking hazards, environmental pollution, infectious
diseases and use of sub-standard materials in our diet, etc. The
younger generation, which comprises the majority of the population,
should be targeted. Public education can be achieved through printed
matter, television and radio.
Cancer Prevention and Early Detection
WHO estimates that one-third of cancers can be prevented and one-third
could be treated if diagnosed early enough, and if access to knowledge
and treatment were widely available. The majority of cancers, which
are related to lifestyle and environment, can be prevented or their
incidence decreased by such measures as educating people about the
dangers of smoking, and vaccinating them against Hepatitis B, etc.
These measures should be targeted to schoolchildren and young adults.
Early detection of several cancers such as breast, cervix, colon
and other sites that can be effectively treated in their early stages
would significantly increase survival rates. Breast self-examination
and clinical breast exam.ination are important and much less expensive
potential alternatives to mammography. Direct visualization of pre-invasive
cervical cancers is also a cheap and highly effective means of preventing
invasive cancer. For screening programs to be established, we need
to allocate resources to the common cancers in our region and to
use our resources pragmatically.
Treatment Options
Cancer patients are treated with a variety of protocols developed
in developed countries. These protocols may not always be appropriate
for patients living in the less developed countries. It is important
that indigenous protocols are developed, keeping in mind resources,
the biology of the disease and the patients’ biology. It is also
important that treatment should be provided to the maximum number
of patients given the financial constraints. Last but not least,
at present the vast majority of patients require palliation for
their symptoms and maximum comfort should be provided to them. Herculean
efforts are still needed to see the proverbial light at the end
of the tunnel.
Zeba Aziz, Professor of Oncology, Allama Iqbal Medical College,
Lahore
|
 |
|