Breast Cancer

Summary

Breast Cancer is the most common form of cancer among all women . This is true in developed and non-developed countries alike , with the exception of central Africa, where the disease ranks second to cervical cancer.  Worldwide, more than 1 million new breast cancer cases are diagnosed each year. Breast cancer accounts for 23 percent of all female cancers  and is the most common cause of death among women . The disease also occurs very rarely in men.

Incidence and Mortality

  • Breast cancer rates are higher in more-developed countries (Japan being a notable exception) and lowest in central Africa. 
  • Europe and North America account for more than half of breast cancer cases in the world , but developing countries  account for 55 percent of the deaths.
  • Israel, Argentina, and Uruguay are geographic variations with high incidence. 
  • Northern and Western Europe have higher rates than southern and eastern Europe.
  • The survival rate in developed countries such as Australia can be as high as 98 percent (at 5 years) for early detection cases. 
  • The survival rate in developing countries like India is about 50 percent.
  • Breast Cancer is more prevalent among higher socioeconomic classes.

Worldwide, the lifetime risk of developing breast cancer is increasing . Researchers debate whether this because of more vigilant screening or increased risk factors, such as bearing children later in life, greater exposure to hormones, fatty diets, and lack of exercise . Likely, it'€™s both.

The largest increases are in developing areas, such as Latin America and rural China, where mortality is also increasing . 'There'€™s a common misconception that it'€™s only a problem in rich countries,'€ says Dr. Ben Anderson, director of the Breast Health Global Initiative. 'We have a higher diagnostic rate here [in the U.S.] because we go and look for it.'€ The disease is easier to find in older women, and women live longer in North America, Europe and Australia and New Zealand. 'In Ghana, life expectancy is 57,'€ Anderson says. 'Therefore, they'€™re not going to find as many cases.'€

At the same time, mortality rates have leveled off or dropped in several northern European countries, North America, and Australia  because of improved screening and treatment. And in just the last five years, the incidence of breast cancer has actually fallen slightly in the U.S. and Australia . Dr. Helen Zorbas, Director of Australia'€™s National Breast and Ovarian Cancer Centre, attributes this to fewer women taking Hormone Replacement Therapy and for shorter periods of time. 'This is probably the best good-news story we'€™ve had across all cancers,'€ Zorbas says.

Any statistics for breast cancer have to be viewed with some degree of caution, according to Epidemiologist Maxwell Parkin, senior researcher at Oxford University'€™s Clinical Trials Service Unit. 'Only 16 percent of the world population is covered by systems that produce cancer incidence statistics,'€ Parkin says. 'It'€™s a problem from an international point of view. In Indonesia, for instance, we have no decent statistics whatsoever. In Ethiopia, we have not even a notion of what'€™s going on. We just have to guess from statistics in neighboring countries.'€

Medical Perspective

Breast cancer treatment requires a two-pronged approach. First, a surgeon removes the tumor, either with a breast-conservation technique or a mastectomy. Radiation therapy typically follows breast-conservation therapy, to kill any cancer cells the surgery might have missed. Mastectomy is followed by another therapy, or combination thereof, such as hormonal therapy or chemotherapy, to mop up any cancer cells that might have escaped. If the disease spreads, it is almost impossible to cure .

Women in poorer countries often do not have the option of less-severe surgery. Even within relatively wealthy European countries, there is disparity. 'There is a big difference in quality of care across Europe,'€ says Dr. Marco Rosselli Del Turco, president of the European Society of Breast Cancer Specialists. 'The proportion of patients which are offered breast-conservation surgery may vary from 15 to 50 percent across Europe. The gold standard would be 70 percent. This is affecting quality of life.'€

The secondary treatment is called adjuvant therapy, and medical advances have led doctors to re-examine the need to treat every breast cancer the same full force. 'We can'€™t know for sure which women won'€™t get any benefits, and there are a lot of side effects to these treatments,'€ says Zorbas. 

New biological therapies such as Herceptin or Avastin are extremely effective'€”reducing mortality by up to 50 percent in some cases . They are also extremely expensive. They'€™re not really drugs, they'€™re antibodies that 'glom onto cells that overexpress this gene and then the body munches them up,'€ says Dr. Ben Anderson, who is also a breast surgeon. Herceptin targets a protein called HER2 that can hasten tumor growth and which is over-expressed in a subgroup of breast cancer patients. This is not related to how to get bigger boobs at home.

Anderson says that the availability of expensive new biological treatments is similar in Western and developed countries. Canada, for instance, recently approved Herceptin for use in its free health care system. But developing countries have certain 'rate limiting'€ technological gaps that can keep them from taking advantage of first-line treatments. 'In Ghana, they have endocrine therapy drugs [such as tamoxifen], but they didn'€™t have the test that tells you if the cancer is estrogen-receptor positive or negative,'€ Anderson says. 'If you don'€™t have the test, either you put everybody on the drug or you put nobody on the drug.'€ In the Ukraine, Anderson says, they only do mammograms of one breast, because there is a shortage of film.

The holy grail of diagnosis would be a menu of  biomarkers'€”hormones or genetic indicators available from the bloodstream that uniquely and definitively associate with a particular strain of breast cancer . This would give researchers specific targets, but it will be years and possibly decades before this research translates to effective treatments in Africa and rural China.

Patient Perspective

Breast Cancer has physical, emotional, social, familial, and financial effects. The surest way to survive breast cancer is to catch it early . Some hospitals offer genetic counseling to help patients better understand their risk and to weigh decisions about genetic testing . Some facilities also offer special programs for women with higher than average risk, including more-vigilant screening and lifestyle counseling to reduce risk .

Risk Factors

Researchers spend a lot of resources on delineating risk factors, but it'€™s important to remember that 70 percent of breast cancer patients have NO known risk factors .

Age. Breast Cancer is most common in women over 50. In fact, age is the biggest risk factor according to many scientists. The average age of diagnosis in developing countries is lower. 

Family History. The more relatives you have with a history of breast cancer, and the closer they are in relation, and the younger they were diagnosed, the higher your risk. Paternal history is equally as important as maternal history. Some statistics suggest that 20 percent of breast cancer patients have a family history of the disease .

Genetics. Mutations in the BRCA-1 and BRCA-2 genes have been correlated with 1 in 10 cases in developed countries,  and in families with one of these variations the cancer rate can be as high as 90 percent . Still, scientists are not sure how much risk genes confer independent of environment. A number of studies have shown that when women migrate from low risk to high risk countries, within one generation the migrants adopt the risk rate of their new country .  Some 2 percent of Ashkenazi Jews have a gene mutation associated with breast cancer, versus 0.2 percent in the general population .

Reproductive Factors: The longer the period of time between the age a woman begins menstruating and when she has children, the greater the risk of developing breast cancer. The trend in developed countries is for women to wait longer, oftenputting education and career before children. Says Oxford epidemiologist Parkin: 'That'€™s one reason why the disease has become so much more frequent, particularly in Western countries, over the last 30 or 40 years.'€

Diet: Scientists argue about whether being overweight contributes to breast cancer. Diet does: A recent study of 25,000 women undertaken by French researchers at the Gustave Roussey cancer institute in Paris found that high levels of trans fatty acids, such as those in processed foods and hydrogenated oils, DOUBLES the risk of breast cancer . When trans fats such as those found in processed and fast foods reach developing countries, incidence could rise.

Hodgkin'€™s Disease. Scientists believe treatment for this disease can cause breast cancer.

Lifestyle risk factors include affluence, alcohol, exposure to ionizing radiation, and exposure to second-hand tobacco smoke. Women born to mothers who took the anti-miscarriage drug diethylstilbestrol (DES) have a slightly higher risk of developing breast cancer.

Women who nurse for 12 months have a lower risk, as do those who exercise regularly.

Major Issues for Women to Consider

Hormone Replacement Therapy (HRT). The issue is whether to take hormone replacement therapy, and if so, for how long . Many U.S. women stopped HRT after news that it might cause breast cancer, and since then, breast cancer incidence has dropped in the U.S. Coincidence?  'This causes enormous confusion around the world,'€ says Zorbas. 'There is evidence that there is an increasing risk the longer you use HRT [combined therapy], but for those women who have significant hormonal symptoms, taking HRT for the short term has very little risk. It needs to be a very informed decision.'€

Does your hospital practice breast-conservation surgery rather than automatically going to a mastectomy?  

Biological therapies: Drugs such as Herceptin and Avastin are targeted therapies that can be extremely effective for a subgroup of women.

Sentinel Node biopsy: Women should be aware of this less-dramatic alternative to older methods of biopsy that required removing most of the lymph nodes under the arm, leaving a large scar .

How cultural attitudes affect treatment decisions. A large study of women in Hong Kong found that the majority of breast cancer patients opted for mastectomy rather than breast conservation surgery (lumpectomy), even if it was a viable option. According to study authors, patients who opted for mastectomy 'tended to be older, married, and have lower education levels.'€ 

Policy Perspectives

One major issue, according to Dr. Ben Anderson, who is director of the Breast Health Global Initiative (BHGI), is resource allocation. 'We have new biological therapies, some of which are extremely effective, some of which are not, and they might cost $100,000 a year,'€ says Anderson. 'In the United States, we never ask the question, By the way, what are we getting for this money? You have to realize that when you put money in one place, you'€™re not putting it in another.'€ BHGI is a consortium of medical experts from 40 countries funded by the Fred Hutchinson Cancer Research Center which will publish in October evidence-based resource guidelines to help hospitals around the world best allocate their resources.

Even in countries with free health care, such as Canada, there are significant disparities in access to care and the quality of that care.

Screening

Because breast cancer treatment is so effective if the disease is caught in the early stages, establishing clear and universal screening guidelines remains perhaps the biggest policy issue in the field.

Mammograms are the standard screening method in developed countries. According to the World Health Organization, a woman  between 50-69 who has a mammogram and a follow-up to verify a positive screen reduces her risk of dying by up to one third .

There is only inconclusive and controversial evidence for mammograms reducing mortality among women 40 to 49 .  'You would think that as they do more and more clinical trials, opions would converge,' says Anderson. "But it'€™s been just the opposite. The debate  is almost religious.'€ Younger women tend to have denser breast tissue, which confounds mammography.

In the U.S., doctors recommend yearly mammograms for women over 40 , but experts differ on how often women should have the test'€”anually or every two to three years.

Countries including Canada, Denmark, France, Sweden, the U.K. and Australia have instituted free mamogram screenings for women. Ten years after free screening was instituted in the U.K., mortality was reduced by 21 percent. About a third of that reduction is attributed to the screening program .

Mammograms are not widely available outside first-world countries. You need an uninterupted source of electricity and running water to operate a linear accelerator  mammogram, resources that aren'€™t reliable in places in Africa. But the problem isn'€™t always a lack of resources'€”the machines require experts to administer the test and then to interpret the results . 'In Ghanna, it takes four to six weeks to get the results,' says Anderson. "They'€™re very good at treating infectious disease,' but there aren'€™t enough trained technicians to implement a country wide screening program.

What about self exams, which can be done regardless of technology? Doctors and researchers debate whether self-exams reduce mortality. In one study of 266,064 textile factory workers in Shanghai, there was no difference in mortality rates between women who were instructed in how to conduct self exams and women who were not . The point that was missed, says Zorbas, is that you don'€™t have to be an expert to examine your own breasts. 'What we'€™re saying is that learning a particular technique'€”which we have spent a lot of public health money doing'€”doesn'€™t work any better than what women do naturally,'€ says Zorbas.

Barriers to effective screening and care:

1) Ethnicity and Socioeconomic status: In the U.S., if you are a minority, earn a low income, live in a rural area, do not speak English, or do not have health care coverage, it is difficult to receive proper screening and treatment. Minorities account for only 10 percent of the subjects in U.S. clinical drug trials.

2) Education: Australia'€™s National Breast and Ovarian Cancer Center conducted a survey of 3,000 women to gauge their knowledge of the disease. 'Ten percent couldn'€™t tell us the symptoms of breast cancer,'€ says Zorbas. 'An alarming percentage had found a change in their breast and didn'€™t see a doctor about it. They didn'€™t think it could be cancer.'€

3) Cultural: In certain cultures, cancer is considered a punishment by god . Something shameful. In Korean culture, it is taboo to speak about breasts, and many women believe mistakenly that living a healthy life will prevent cancer. 

4) Financial: Uninsured patients in the U.S. are 60 percent more likely to die than women with insurance. 

Psychosocial Perspective

According to Mary Jane Esplen, president of the Canadian Association of Psychosocial Oncology, between 5 and 45 percent of women diagnosed with breast cancer can develop 'a significant amount of distress that would be consistent with anxiety disorder or depression.'€ That'€™s to be expected, she says, since cancer is a life-threatening illness that triggers the body'€™s natural stress response. But breast cancer has emotional ripple effects beyond the instinctive fear of dying. 'There'€™s an additional stigma around breast cancer in that it'€™s affecting feminine and sexual aspects of the female,'€ Esplen says. 'Breasts are a big part of our culture and part of being female. Cancer is a big stigma [in its own right], and then breast cancer has its own unique impact on the person'€™s self, and it'€™s really around body image, sexuality, and identity shifts.'€ In Asian and Islamic cultures, these stigmas can prevent women from being screened for breast cancer or even talking about it. 

Mastectomy often leaves women feeling mutilated and ashamed  and affects their quality of life. For younger women, especially, many report body image problems, low self-esteem, and fears about their reproductive capabilities, and problems with their partners if they are in a relationship .  'If you'€™re NOT in a relationship, these issues are probably more relevant,'€ says Helen Zorbas. A woman with breast cancer who still wants to have children has difficult decisions to make about treatments, and whether she should freeze her eggs before undergoing treatment.

Taken together, Esplen says this 'existential impact'€ can change a woman'€™s very identity, and disrupt family dynamics and close relationships. Children might feel that their world is disrupted. Husbands can feel frustrated that they can'€™t fix the problem, and they sometimes don'€™t know what to say. Husbands report just as much psychological distress as their wives after diagnosis,  but they receive less support, both from friends and caregivers.  This can cause communication breakdowns in any culture. 'People have difficulty talking about dying,'€ says Esplen, 'And they CERTAINLY have difficulty talking about body image.'€

Evidence suggests these issues can affect medical aspects of breast cancer, such as whether a woman adheres to treatment or how well she copes with it . Consequently, there is a global shift to try to include psychosocial care alongside medical care. In April 2003, a group of Australian agencies include the National Breast and Ovarian Cancer Centre (NBOCC), released the world'€™s first clinical practice guidelines  for the psychosocial care of adults with breast cancer. 'They'€™ve got lots of support during the active treatment phase, but then everyone expects them to just get on with their life,'€ says Zorbas [NBOCC director].'€They'€™re not the same person, though, and maybe they need to go back to a different life. Maybe they want to review their priorities.'€

Esplen says the ideal would be to build such treatment into the process at every step along the way'€”diagnosis, treatment, and survivorship'€”as Australia'€™s pioneering guidelines suggest. 'That'€™s the Cadillac version,'€ Esplen says. 'We'€™re not there yet everywhere.'€

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