breast cancer risk factors and triggers

The genetic risk factors for breast cancer to develop are age, being a female, and having a family history of the tumor. In developed countries the risk of breast cancer in women at the age of 29, 39, and 49, is, respectively, one in 2000, one in 215, and one in 50. The lifetime risk of breast cancer reaches the highest values in women 70 and older: one in eight !. In the latter age group the incidence has progressively increased in the last fifteen years as it was one in ten in 1997 and one in nine in 2003. Why is it happening?  Cancer is a genetic disease but it needs some triggers to develop. There is now a good evidence that triggers of breast cancer can be found in lifestyle and environment and most probably are the followings: having fewer children and in later life; reduced breastfeeding; widespread hormone replacement therapy  (administered to contrast the debilitating symptoms of the menopause); increased alcohol consumption, and excess of weight (especially after menopause).  Oestrogen and other hormones are strongly implicated in breast cancer, and both pregnancy and breastfeeding reduce the amount of circulating hormone. Each birth decreases the risk of breast cancer by 7%. Every year of breastfeeding cuts the risk by 4.3%.

Women in developing countries have lower rates of breast cancer mainly because they start to have babies at a much younger age  and have higher parity. In Sub-Saharan Africa, higher incidence rates and relative frequencies of breast cancer have been reported in association with urban than with rural residence but, in any case, the incidence of the disease is much higher among white women in Africa than among black African women. Notice that this is just the opposite of what has been reported for afroamerican women as compared to white women in the USA (see my previous post on the topic).   In the future decade a progressive change in women’s lifestyle (on the model of western women) will probably take place also in many countries of the African continent and this will parallel a rise in breast cancer incidence. We should get prepared: the fight against breast cancer can be successful only if local health systems provide early diagnosis and proper treatment facilities.

Village health workers’ role in primary prevention of diseases

plumeria (frangipani)

Villagers in many developing countries rarely see doctors or nurses. In fact, a fraction of medical graduates and nurses of English speaking parts of Africa or southern Asia, often emigrate to wealthy countries (Canada, USA, UK and Australia) as they are attracted by better pay and working conditions. Those doctors who, instead, remain in their home country tend to stay in the cities and not in rural areas.  Similarly, nurses are rarely tempted by rural villages. Doctors and nurses, however, are not necessary to improve rural health in developing countries. Two very successful programs in desperately poor parts of India’s Maharashtra State which were described in an interesting report appeared in the New York Times show that people with no or little formal medical training do successfully substitute for doctors and nurses. Once properly trained, these ordinary women and men help prevent most rural sickness by teaching people very simple acts such as the use of clean water, waste-disposal systems and more diverse farming. As a matter of fact, village health workers do have a huge impact on the health and prosperity of the community they serve. They visit pregnant women repeatedly, attend births, teach mothers about how to keep their babies healthy and check in on the children often.  They teach new mothers how to feed and care for their babies and how to treat diarrhea and fever. Children get regular immunizations, and tuberculosis,  scabies and leprosy are properly and effectively prevented. The main role of these health rural workers is teaching the community some essential preventive measures. Their potential role also in the prevention of HIV infection and cancer of the cervix uteri in young women should be properly and adequately stressed. They can really induce a major behavioral change in sex habits of the population by means of interpersonal communication activities. Health workers should be trained on this topic too and prevention of tumors should become a novel goal of these programs.

AIDS prevention in Zimbabwe

tropical nymphaea

According to the United Nations, about 33.3 million people worldwide are infected with HIV and the majority of those live in sub-Saharan Africa. The virus can be controlled with cocktails of drugs, but there is no cure and nearly 30 million people have died of HIV-related causes since the disease first emerged in the 1980s. The good news is however that the disease has taken a dramatic downturn in Zimbabwe, a country where its incidence was among the highest in the world. In fact, people infected with HIV were 29% in 1997 but ten years later, in 2007, they were 16%. How was it possible? The answer is: primary prevention. Zimbabweans have primarily been motivated to change their sexual behavior because of increased awareness about AIDS deaths which heightened their fears of catching the human immunodeficiency virus that causes it. The behavioral changes associated with HIV reduction consisted mainly in reductions in extramarital, commercial, and casual sexual relations, and associated reductions in partner concurrency. These changes were probably aided by prevention programs utilizing both mass media and church-based, workplace-based, and other interpersonal communication activities. The main lesson emerging from these data which were published in the PloS medical journal online is that, unless prevention efforts can be made more effective, there will ultimately be no victory in the fight against HIV/AIDS. This lesson is for all countries worldwide.

HIV, HPV and cervical cancer in developing countries

Both Cervical cancer and HIV infection are sexually transmitted diseases with no immediate visible symptoms. Cervical cancer originates from a sexually transmitted disease named Human Papilloma virus (HPV) which silently grows in the cervix and later develops to invasive cervical cancer. There is a growing evidence in the medical literature that a difference exists between HIV/AIDS positive and HIV negative women in the incidence and aggressiveness of cervical cancer, and this latter tumor is now regarded as an AIDS defining illness. This is particulary true in the low income developing world. Researchers suggest that as women are living longer due to access to specific anti-retroviral drugs, they are at an increased risk of contracting cervical cancer. While access to antiretroviral therapy is beginning to reduce AIDS mortality worldwide, gynaecologic oncologists warn that women being treated for AIDS could end up dying of cervical cancer unless they have access to appropriate screening and treatment. In fact, HIV positive women commonly show invasive cancer ten years earlier than women who are HIV negative. Moreover, the incidence of the precursor of cervical cancer, i.e. cervical intraepithelial neoplasia (CIN) is 4-5 times higher among HIV-infected than HIV-negative women and girls. In conclusion, there is a need for successful integration of cervical cancer  and HIV/AIDS service especially in low income developing countries. Great efforts should be made to introduce HPV vaccination in young girls and to implement effective secondary prevention and early diagnosis of cervical cancer in HIV positive women.

breast cancer incidence in 2008 worldwide

Estimated age-standardised rates (World) per 100,000

Using the same source as in the previous post I am reporting the incidence of breast cancer worldwide in 2008.

“Breast cancer is by far the most frequent cancer among women with an estimated 1.38 million new cancer cases diagnosed in 2008 (23% of all cancers), and ranks second overall (10.9% of all cancers). It is now the most common cancer both in developed and developing regions with around 690 000 new cases estimated in each region (population ratio 1:4). Incidence rates vary from 19.3 per 100,000 women in Eastern Africa to 89.7 per 100,000 women in Western Europe, and are high (greater than 80 per 100,000) in developed regions of the world (except Japan) and low (less than 40 per 100,000) in most of the developing regions. The range of mortality rates is much less (approximately 6-19 per 100,000) because of the more favorable survival of breast cancer in (high-incidence) developed regions. As a result, breast cancer ranks as the fifth cause of death from cancer overall (458 000 deaths), but it is still the most frequent cause of cancer death in women in both developing (269 000 deaths, 12.7% of total) and developed regions, where the estimated 189 000 deaths is almost equal to the estimated number of deaths from lung cancer (188 000 deaths). “

It is also interesting to note that although the incidence of breast cancer in developing countries  is significantly lower than in developed countries, mortality due to this tumor is much higher in the former as compared to the latter. As already pointed out in previous posts,  this is due to the lack of efficient screening and early diagnosis of breast cancer in developing countries.

uterine cervical cancer incidence in 2008 worldwide

Estimated age-standardised rates (World) per 100,000

Here are some some updated data on the incidence of cervical cancer worldwide  according to the International agency for research on cancer (IARC). Cervical cancer is the third most common cancer in women, and the seventh overall, with an estimated 530 000 new cases in 2008. More than 85% of the global burden occurs in developing countries, where it accounts for 13% of all female cancers. High-risk regions are Eastern and Western Africa with age standardised incidence rate (ASR) greater then 30 per 100,000, Southern Africa (ASR 26.8 per 100,000), South-Central Asia (ASR 24.6 per 100,000), South America and Middle Africa (ASRs 23.9 and 23.0 per 100,000 respectively). Rates are lowest in Western Asia, Northern America and Australia/New Zealand (ASRs less than 6 per 100,00). Cervical cancer remains the most common cancer in women only in Eastern Africa, South-Central Asia and Melanesia. Overall, the mortality incidence ratio is 52%, and cervical cancer was responsible for 275 000 deaths in 2008, about 88% of which occurred in developing countries.

africa needs a green revolution

Africa’s peasants are migrating to the cities in huge numbers because it is becoming increasingly difficult to survive on their farms. Meanwhile, very few are finding productive jobs in the cities and most are getting poorer. Africa’s dependance on concessionary food import is growing and these trends can have catastrophic consequences for the continent’s poor people. Current situation in Africa bears some striking similarities in Asia in the early 1960s. Faced with worsening food shortages and slow agricultural growth, Asian governments started spending 10-15% of their total budget on agriculture each year because they realised that rapid agricultural growth was a key step along the path to industrialisation. They invested on agricultural research, irrigation, rural roads and power.  Many of these interventions were targeted to small farms, who enthusiastically adopted the new technologies and typically outperformed larger farms. These policies inspired a green revolution that helped transform Asia. Africa, in contrast, has failed to do the same. For over 40 years African governments have spent less than half the share spent in Asia, and little has been done  for agricultural development. Africa has only exploited a fraction of its irrigation potential and the density of rural roads is very low. Farmers rely almost exclusively on rain-fed farming and face exceptionally high transport and marketing costs. Instead, yields could dramatically increase if farmers had access to improved technologies and markets and if goverments provided more supportive policies for agriculture. An African green revolution would generate many productive jobs in agriculture and provide a leg up out of poverty for many. This would help creating allied industries and lowering food prices, and, finally, would prevent migration of millions of peasants off the land. Two risks, however, should be taken into account: a) the spread of green revolution agriculture may affect both agricultural biodiversity and wild biodiversity; b) the consumption of the chemicals and pesticides used to kill pests by humans in some cases may be increasing the likelihood of cancer.
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