A new analysis of data on breast cancer from the World Health Organisation has been presented at a Breast Cancer Symposium at San Antonio, held in December 2016. Cécile Pizot presented the findings of the study which showed that over the last 25 years, the detection and treatment of the disease has significantly changed. Rates of breast cancer have fallen in most of the countries surveyed in the study. The disease is the most common cancer in women worldwide.
The study extracted data and calculated mortality rates from 1987-2013 and organised the results in age groups. A limitation of the study was that data was unavailable for some Latin American, African and Asian populations. The US showed a decline in the mortality rate of 42%. It fell from 22 deaths per 100,000 women in 1987-9 to 14 deaths per 100,000 women in 2011-3. All age groups were reflected in the fall in death rates, but the rates were higher for younger women. This reflected a global trend where more younger women were surviving for longer at the end of the period covered by the data. The scientists suggested that this could be because younger women receive more intense treatment such as longer chemotherapy. This can prolong their survival.
There was no clear data that indicated whether breast cancer screening played a role in reducing mortality. The study showed that several nations that had similar geographical locations and socio-economic status experienced similar results even though some of those nations had been screening for breast cancer since the 1980s while others had only introduced it in 2005 or even later.
The data showed that mortality due to breast cancer declined in 39 out of 47 countries. England and Wales had the sharpest decline (46%). The researchers suggested that this was due to advances in detection and treatment. Other developed European nations also experienced drops in death rates. The results were more mixed in the Latin American nations. In Argentina and Chile, mortality rates for women decreased across the ages, while in Brazil and Colombia, they increased, also across all the ages surveyed.
The most dramatic increase in mortality rates was seen in South Korea. The death rate rose by 83% and there was a higher mortality in all the age groups, although the rate was still lower than that of the United States. The scientists suggested that the country has experienced major changes in its society since the 1950s and had evolved very quickly from an agricultural country to a Westernised country which was now highly industrialised. This could account for the increase in cancer mortality rates.
The scientists found it difficult to find a single common factor that could have a major influence on the mortality rates. The countries’ health care systems were so different that it was difficult to compare them. The researchers suggested that future studies could focus on drug therapies, care access, risk factors or the use of multi-disciplinary teams.
The World Health Organisation maintains that early detection and treatment is key to maintaining the downward trend of mortality rates due to cancer.
Pizot C, et al. Overview of breast cancer mortality trends in the world. Presented at: 2016 San Antonio Breast Cancer Symposium; December 6-10, 2016; San Antonio, TX. Abstract P5-08-04.
World Health Organization, Breast Cancer: prevention and control
If you enjoyed this article, you might be interested in some of our BSE educational products:
Ideal poster for waiting rooms at GP surgeries or consultant waiting rooms
Ideal educational model for patients
This BSE model is available as a B or a C cup for extra realism