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PUBLIC HEALTH

Five years later

Study spanning 71 countries shows that survival rates for prostate cancer rose and pediatric cancer fell in Brazil

Slide with tissue samples used for identification and analysis of tumors at the A.C. Camargo Cancer Center in São Paulo

Léo Ramos Chaves

Nine out of 10 men with prostate cancer in Brazil live at least five years after beginning treatment. This survival rate is equal to that of Germany and close to Japan and the United States, which are only slightly behind the Mediterranean island of Cyprus, where virtually all patients with this type of cancer live longer than five years. The same study that presents this data, which was published in January in The Lancet, shows that Brazil has the lowest overall survival rate for brain cancer in children: almost four patients in 10 survive five years, a result which is far from Iceland, where nine of every 10 patients live more than five years.

With some good results and other not so good results, Brazil was in the middle of the field in the third version of the Concord, an international program for global cancer survival monitoring coordinated by epidemiologist Michel Coleman, a professor at the London School of Hygiene and Tropical Medicine, which examined five-year survival rates in 37.5 million patients with cancer in 71 countries and territories from 2000 to 2014. In this study, the United States, Canada, Australia, New Zealand, Finland, Iceland, Norway, and Sweden had the highest five-year survival rates for most of the 18 types of cancer analyzed. Survival increased as a general global trend, even in the most lethal types such as cancer of the liver, pancreas, and lung, although sharp contrasts can still be seen between countries.

During the 15-year period, five-year survival for women with breast cancer was 90.2% in the United States, 66.0% in India, and 0% in the African country of Mali (see graph). In Brazil, between 2000–2004 and 2010–2014 survival in adults with pancreatic cancer increased 141% and in women with breast cancer rose 9.5%, while survival for children with brain cancer fell 48% and for adults with lung cancer dropped 20%.

“Patient survival for the 18 types of cancer is closely linked to the human development index of each country and access to the health system,” says epidemiologist Maria Paula Curado, a researcher at the A.C. Camargo Cancer Center in São Paulo who participated in the study. “In Brazil, for some types of cancer more than 70% of cases are diagnosed at an advanced stage, which hinders treatment and reduces survival.”

Brazil participated with information provided by six cities: Aracaju, Cuiabá, Curitiba, Goiânia, Jaú (São Paulo), and São Paulo. These data covered 134,597 patients, the equivalent of 7.7% of the total number of people receiving treatment for cancer in the country. “We should have examined the survival of at least 80% of the patients treated in Brazil,” says Curado, who created the Goiânia cancer patient database and managed it from 1988 to 2006. “Most cities did not send information because the records were incomplete or were poor quality, which reinforces the need to support the teams responsible for population-based cancer records in Brazil.” Of the 71 countries, 41 participated with their national data, while others such as Brazil contributed with smaller databases.

“We need to know why the population does not have access to better forms of treatment and improve our survival rates,” says epidemiologist Gulnar Azevedo e Silva, director of the Institute of Social Medicine at Rio de Janeiro State University (UERJ) and one of the coauthors of the Lancet article. “The five-year survival rate for women with cervical cancer in Brazil is 60% but should be higher, because it is completely avoidable; in Europe it is already a rare disease.” According to the National Institute of Cancer (INCA) in Rio de Janeiro, nearly 600,000 people are thought to have received a diagnosis of any type of cancer across Brazil in 2016. Each year this disease causes 225,000 deaths throughout the country.

Azevedo e Silva coordinated a study published in 2016 in PLOS ONE indicating that 34.2% of the cases and 42% of the deaths associated with 25 types of cancer in Brazil which are expected to occur in 2020 could be avoided. This is because they stem from factors related to lifestyle or the environment, such as smoking, low fruit and vegetable intake, overweight, excessive alcohol consumption, infections, and continuous exposure to the sun and pollution. Smoking is responsible for about 30% of cancer deaths, especially lung cancer, which presented a five-year survival rate of 8.5% in Brazil, far below the survival rate of 32.9% recorded in Japan.

Joel Silva / Folhapress Women wait their turn for examinations in a bus containing mammography equipment in Barretos, São Paulo, in 2003Joel Silva / Folhapress

Supply and demand
Azevedo e Silva and psychologist and epidemiologist Jeane Glaucia Tomazelli, a researcher at INCA, examined medical care for women with breast cancer; the Concord study registered a five-year survival rate for this cancer of 75% in Brazil and 90.2% in the United States. The researchers found that although patients are encouraged to get mammographies, diagnosis and treatment services in the public health network fall far short of the population’s needs.

As detailed in a 2017 study in the journal Epidemiologia e Serviços de Saúde (Epidemiology and health services), with 27 mammograms per 100 women Brazil is still well below the recommended rate of 50 of these examinations per 100 women. In the state of Rio de Janeiro, 44% of the cases of breast cancer were diagnosed in advanced stages, even though 68% of these women lived in cities that offered specialized medical services to diagnose and treat the disease. The researchers found that despite the recommendations by the Ministry of Health (MOH) to control breast cancer, information systems containing the list of women to be called for examinations and followed over the years are still scarce.

There are also regional inequalities, which hinder access to early diagnosis and surgery. According to this study, northern Brazil has one mammography machine per 100,000 women, while in the south there are two for this same number. The north also has fewer professionals specialized in breast surgery (102 per 100,000 women), again in contrast to the southern region (244 per 100,000).

“If a woman has a mammogram showing suspected breast cancer,” says Azevedo e Silva, “she should have to wait at most four weeks for a biopsy to confirm the diagnosis and another four to begin treatment.” She believes more agility and continuous processes for reformulating and monitoring results are needed.

One of the recommendations for cancer control announced by the World Health Organization (WHO) is just this: to speed diagnosis and ensure appropriate treatment for all potentially curable types of cancer, such as acute myeloid leukemia in children. The survival rate for this type of cancer was 66% in Brazil, 89% in the United States, and 91% in Germany. “We have to prevent, diagnose, and treat immediately,” says Maria Paula Curado. “The chance of curing a tumor in the initial stage is 90%, but drops sharply in the advanced stage.”

Economic losses
Each cancer death in Brazil generates an average economic loss of R$176,000 (R$147,000 for women and R$197,000 for men), according to a study published in January of this year in Cancer Epidemiology. The losses were calculated based on the average income of economically active persons aged 15–65. The 87,000 premature deaths due to cancer each year in Brazil are thought to result in losses estimated at R$15 billion, the equivalent of 0.21% of the gross domestic product (GDP). “Although part of the labor force is replaced, the study shows the macroeconomic impact of cancer, with the loss of people who fail to contribute to the economy with the income from their work,” says epidemiologist Marianna de Camargo Cancela, a researcher at INCA and coauthor of the study.

The research was coordinated by economist Alison Pearce, a researcher from the Sydney University of Technology in Australia, and examined the BRICS bloc (Brazil, Russia, India, China, and South Africa). In the five countries, cancer deaths result in losses estimated at US$46.3 billion (about R$150 billion) per year (see table).

Deaths from lung cancer have resulted in major losses in productivity, especially in Russia (US$1 billion) and Brazil (US$0.5 billion). “We are seeing the effects of smoking 20 years ago,” says Cancela. “The campaigns do not reduce mortality immediately, because lung cancer develops slowly and takes a while to manifest.”

The authors of the study argue that these results indicate how cancer prevention and access to better forms of treatment may impact not only people’s lives, but also the economy of the countries where they live.

Scientific articles
ALLEMANI, C. et al. Global surveillance of trends in cancer survival 2000–14 (CONCORD-3): analysis of individual records for 37 513 025 patients diagnosed with one of 18 cancers from 322 population-based registries in 71 countries. Lancet. On line. 30 jan. 2018.
AZEVEDO E SILVA, G. et al. The fraction of cancer attributable to ways of life, infections, occupation, and environmental agents in Brazil in 2020. PLOS ONE. v. 11, n. 2, e0148761. fev. 2016.
TOMAZELLI, J. G. e SILVA, G. A. Rastreamento do câncer de mama no Brasil: uma avaliação da oferta e utilização da rede assistencial do Sistema Único de Saúde no período 2010-2012. Epidemiologia e Serviços de Saúde, v. 26, p. 713-24. out.-dez. 2017.
PEARCE, A. et al. Productivity losses due to premature mortality from cancer in Brazil, Russia, India, China, and South Africa (BRICS): A population-based comparison. Cancer Epidemiology. v. 16, n. 53, p. 27-34. abr. 2018.

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